Electrical vestibular stimulation to improve static balance in older adults: a randomized control trial

Electrical vestibular stimulation to improve static balance in older adults: a randomized control trial | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Electrical vestibular stimulation to improve static balance in older adults: a randomized control trial Jordan A. King, Noah Walters, Nadine Rodrigues, Jenna Al Bastami, and 11 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-6349795/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 31 Oct, 2025 Read the published version in Journal of NeuroEngineering and Rehabilitation → Version 1 posted 11 You are reading this latest preprint version Abstract Background Falls are the leading cause of injury-related hospitalizations among older adults, often linked to vestibular dysfunction. While vestibular rehabilitation therapy is a standard intervention, designed to compensate for vestibular impairment with proprioceptive and visual ques, potential cumulative effects of Electrical Vestibular Stimulation (EVS) on balance improvement in older adults are not well understood. Objective This study evaluated the efficacy of cumulative EVS dosing in improving static balance, its potential mechanisms, and clinical significance. Methods A single-blind, randomized controlled trial enrolled 40 older adults (mean age: 77.7 ± 11.8 years). Participants were randomly assigned to a Stimulation group (EVS intervention) or Sham group. The EVS regimen included low-amplitude wideband stimulation (± 0.35 mA, 0–300 Hz) for 20 minutes, three times weekly for six weeks. Balance performance was assessed using a head-mounted sensor to measure postural sway (‘phybrata’) power in four static conditions: Floor EO, Floor EC, Foam EO, and Foam EC. Follow-ups occurred at 3 months and 6 months post-intervention. Results The Stimulation group exhibited significant and sustained reductions in phybrata power, particularly in Foam EO and Foam EC conditions, with improvements observed as early as Day 3 and persisting through 6 months. Additionally, the Sham group demonstrated smaller reductions in phybrata power, potentially reflecting a learning effect. Conclusion EVS is a safe and effective intervention for improving balance in older adults. Its benefits in addressing age-related deficits in balance and sensory integration highlight its potential for fall prevention and rehabilitation. Vestibular System Balance Control Aging Electrical Vestibular Stimulation Galvanic Vestibular Stimulation Postural Sway Vestibular Therapy Balance Therapy Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Introduction Every year, 20–30% of older Canadians report experiencing a fall, making falls the leading cause of injury-related hospitalizations in this demographic [ 1 ]. This incidence rises to 32–42% among those aged 70 and older [ 2 ]. Prior research has identified dizziness and imbalance as prevalent in up to 30% of older adults, with the risk of falls increasing significantly after the age of 60 [ 3 ], [ 4 ]. Falls cost the Canadian healthcare system ~ $ 10.3 billion per year [ 5 ]. Injury due to falls can negatively impact the quality of life for older people and can lead to social isolation, loss of autonomy, bone fractures, reduction in mobility, and increased risk of osteoarthritis. As the global population aged 60 and over is projected to increase from 12–22% by 2050, the search for effective treatments for balance deficits associated with aging becomes increasingly urgent [ 6 ]. Human static and dynamic balance depends on central nervous system (CNS) integration and processing of somatosensory, visual, and vestibular sensory inputs to generate motor control outputs [ 3 ], [ 7 ]. Dysfunction in any of these systems can lead to dizziness or imbalance that can result in a higher risk of falls in aging populations [ 8 ]. Within the vestibular system, there are the otolith organs and semicircular canals which detect movement, providing linear and rotational acceleration information, respectively, to the vestibular nuclei via the vestibulocochlear nerve. Cortical projections to the cortex, then process these inputs, providing essential information about head orientation and stabilizing posture and gaze [ 7 ]. These pathways within the vestibular system collectively manage static and dynamic balance, gait, and posture in humans [ 9 ], [ 10 ]. Vestibular dysfunction is common among older populations [ 3 ], [ 7 ]. Age-related degeneration affects nearly every type of vestibular-related cell and neural connection, including sensory end-organ hair cells, afferent nerve fibers, scarpa ganglion cells, vestibular nucleus neurons, and Purkinje cells within the cerebellum [ 7 ], [ 10 ]. This general loss of input and central integration of vestibular signals results in increased balance deficits with aging. Multiple pathophysiological mechanisms have been proposed to explain vestibular dysfunction in aging. The most common cause of balance dysfunction is the loss of mechanosensory hair cells [ 11 ]. However, given the poor correlation between clinical and histological findings, it is suggested that the vestibular system has compensatory mechanisms that can mask the effects of degeneration [ 7 ]. One example of a compensatory mechanism is central gain enhancement, where vestibular processing is amplified within the central nervous system (CNS) [ 12 ], [ 13 ], [ 14 ]. Other hypotheses suggest neuroplasticity in the central vestibular pathways [ 12 ]. Balance and gait stability begin to deteriorate once peripheral and central vestibular deficits surpass the compensatory capacity of the system [ 12 ], [ 15 ]. Currently, vestibular rehabilitation therapy (VRT) is indicated for nearly all vestibular injuries, excluding unstable lesions and ongoing labyrinthine pathology [ 16 ]. The mechanisms behind VRT include vestibular adaptation, which relies on readjusting the gain of vestibular reflexes, and vestibular substitution, which uses alternative sensory strategies (visual and proprioceptive) to replace vestibular function [ 16 ]. A growing body of research suggests that noisy Electrical Vestibular Stimulation (nEVS) is a promising approach to improving age-related declines in vestibular function [ 17 ], [ 18 ], [ 19 ], [ 20 ], [ 21 ]. EVS aims to enhance vestibular function by delivering imperceptible electrical currents to vestibular end organs and afferent neurons via electrodes placed over the left and right mastoids [ 19 ]. One hypothesized benefit of nEVS is that low levels of noise applied to the vestibular system can enhance the detection of sub-threshold signals [ 19 ]. This mechanism is believed to involve stochastic resonance, where the addition of noise enhances the detection of a signal that would otherwise be undetectable [ 19 ]. EVS stimulates hair cells and the vestibulocochlear nerve (CN VIII) evoking vestibular reflexes [ 22 ], [ 23 ]. EVS has the potential to be a feasible, safe, and non-invasive treatment for balance deficits. Studies have identified the clinical applications of nEVS in treating conditions such as Meniere's disease, vestibular neuritis, bilateral vestibular disorders, vestibular schwannoma, Parkinson's disease, central ischemic lesions, motor myelopathies, anxiety, cognitive disorders, memory disorders, and age-related imbalance [ 24 ]. Few studies have examined the effects of nEVS on older populations and there are currently no studies investigating the cumulative impact of repetitive nEVS. During stimulation, older adults had reductions in center of pressure and sway length [ 25 ], [ 26 ]. Testing across a wide frequency range (0.1–640 Hz) at amplitudes of 0.4 and 1.0 mA in healthy young adults indicated that higher-frequency stimulation (up to 640 Hz) was most effective in reducing sway path length and velocity [ 27 ]. nEVS has the potential to improve postural instability, with these gains persisting for multiple hours post-stimulation [ 25 ]. Repeated nEVS sessions may induce further and sustained improvements in postural stability in healthy adults and e populations [ 25 ]. Further research is required to determine the underlying mechanism(s) responsible for the effects observed in previous EVS studies [ 19 ]. EVS-induced changes in balance could result from improved vestibular information processing in vestibular afferents or the activation of cortical regions, but the precise mechanism remains unknown [ 19 ]. There is also no consensus on optimal EVS delivery protocols [ 19 ]. This study aims to advance and build upon existing research by developing a fixed regimen of nEVS dosing designed to maintain and restore vestibular system function and central processing to improve balance performance. The nEVS regimen involved low-amplitude wideband stimulation at ± 0.35 mA from 0 to 300 Hz for 20 minutes, three times a week, over six weeks. We hypothesized that EVS application would induce sustained improvements in static balance and that these cumulative effects would persist up to six months post-stimulation. Methods Participants Inclusion criteria required participants to be older adults, between 50 and 100 years old. Exclusion criteria included individuals with a hearing aid, pacemaker, neurological disorder, or musculoskeletal disorder. Data was gathered from retirement and assisted living communities (n = 20) and in-lab (n = 20) using the same protocol. All procedures were approved by the University of Calgary Conjoint Health Research Ethics Board (Ethics ID: REB22-1006) and retrospectively registered as a clinical trial on February 25, 2025 (NCT06846047). All participants provided written informed consent before participation. Data collection ceased after recruiting 48 participants, with final analyses completed on participants that completed all testing sessions (n = 40). Experimental Design The study used a single-blind parallel randomized control trial design. Computer-generated simple randomization was used to assign participants into two groups, with an equal allocation of 24 participants to the Stimulation and Sham conditions. Group assignments were linked to participant numbers upon enrollment. There was no allocation concealment mechanism beyond participant blinding. The lead researcher was responsible for enrolling participants and sequentially assigning subject numbers in the order of enrollment. Participants were blinded to their group allocation. Additionally, two independent raters, who were not informed of group assignments, reviewed and removed artifacts from the data without participant identifiers. On the final day, participants were asked to identify which group they believed they were in to assess potential bias. During the first visit, participants completed baseline questionnaires (see Questionnaire section for more detail). Participants attended three sessions per week for six weeks, with follow-ups at 3 months and 6 months post-treatment. Each session lasted approximately 45 minutes. All procedures, including participation allocation, intervention administration, and outcome assessments, follow the pre-specified protocol. No study protocols or outcomes changed after the trial commenced. Four balance assessments were administered via a smartphone app before and after stimulation. After the initial balance assessment, electrodes (3.8cm x 4.2cm) were placed bilaterally over the mastoid process and 2 cm from the midline at the C4 level on all participants. (Fig. 1). The Stimulation group received EVS, while the Sham group did not. Participants were seated and not required to complete any tasks during the 20 minutes of EVS dosing. Immediately after EVS, participants repeated the balance assessments. Follow-up sessions required participants to repeat the balance assessments twice, without the 20 minutes of EVS dosing. Participants removed footwear to complete the testing, which included a modified versions of the Romberg Test (a.k.a. modified Clinical Test of Sensory Interaction on Balance; mCTSIB), in which a head-mounted sensor was used to measure the participant’s ability to stand unassisted under four test conditions designed to specifically challenge the vestibular system, vision, and proprioception separately [ 28 ], [ 29 ]. The four balance assessments, each 60 seconds in duration, were carried out in the following sequence: eyes open on a firm surface (Floor EO), eyes closed on a firm surface (Floor EC), eyes open on a soft surface (Foam EO), and eyes closed on a soft surface (Foam EC). The soft surface was a foam pad produced by Node Fitness (16 x 12 x 2.5 inches) used to reduce somatosensory feedback from the feet [ 4 ]. For all tasks, participants were instructed to stand still with their chin parallel to the floor, feet together, and arms by their sides. Investigators stood close to the participant during balance tasks for safety. Electrical Vestibular Stimulation The skin was cleaned with an alcohol swab before attaching the EVS electrodes. EVS involved electrically activating the vestibular system by passing small electrical currents through electrodes placed on both mastoid processes and on both sides of the neck beside the spine at the level of the C4 vertebrae using a custom rechargeable battery-powered, dual constant current isolated stimulator module developed by Neursantys Inc. Participants in the Stimulation group received 20 minutes of EVS dosing at ± 0.35 mA from 0 to 300 Hz. (Fig. 1C). Previous research has indicates that individuals typically begin to perceive vestibular sensations around 0.9-1.0 mA, with cutaneous sensations such as tingling or prickling occurring at similar or slightly lower intensities (0.85 mA) [ 30 ]. Our study design used ± 0.35 mA to maximize participant comfort and justify the single-blinded study design. A frequency of 300 Hz was chosen as higher frequencies have be shown to reduce postural sway compared to lower frequencies [ 31 ]. Both the Stimulation and Sham groups underwent identical procedures, including electrode placement, session duration, and balance assessment. The only difference was the stimulator was turned off for the Sham group. Accelerometry Participants were instrumented with wearable accelerometers (Phybrata Sensor; PROTXX Inc.) placed vertically on their head above the right mastoid process. (Fig. 1B) [ 32 ]. A previous study by Abdollah et al. (2021) validated the PROTXX sensor placed on the head as a measure of gait and balance performance. The accelerometers detect motion of the head in tri-axial directions (x, y, and z) [ 33 ]. Accelerometers were attached to the skin with disposable double-sided medical adhesive tape after cleaning the skin with an alcohol swab. The accelerometers collected data sampled at 100 Hz and automatically relayed the kinematic data to a smartphone app-enabled, cloud data system. Accelerometers were removed after the balance assessments. Figure 2 shows sample EO and EC raw accelerometer times series data and spatial scatter plots collected before and after the EVS treatment. Balance assessments were performed using the smartphone app developed by PROTXX Inc. The app guided the investigator and participant through the experimental procedures using on-screen instructions and auditory cues. All tests described in the Experimental Design section were completed using this app. Questionnaires Five questionnaires were administered during the first visit: the Activity Balance Confidence Scale (ABC), the Symbol Digit Modality Test (SDMT), Headache Questions for Baseline, the Migraine Disability Assessment Scale (MIDAS), and the Physical Activity Scale for the Elderly (PASE). Participants were asked each day if they had experienced any headaches since their previous visit and to rate their severity, with the results averaged over a month and compared between groups. Participants completed the ABC and MIDAS on the last day of the 6-week intervention. The ABC questionnaire measures an individual’s confidence in performing activities without losing balance. The ABC scale has been validated for older adults and is well-suited for identifying community-dwelling seniors who are beginning to lose confidence in their balance and who could benefit from a fall prevention intervention [ 34 ]. The SDMT is a general measure of attention, processing speed, visual scanning, and motor speed by matching numbers to symbols as quickly as possible for 90 seconds [ 35 ]. The validity and reliability of this test has been assessed for many different populations including older adults [ 35 ]. The PASE is designed to assess activities commonly engaged by older adults and is a reliable and validated measure of physical activity for older adults to be used in research [ 36 ]. The MIDAS is a five-item questionnaire designed to measure headache-related disability and it demonstrates good test-retest reliability across population-based samples in the United States and United Kingdom [ 37 ]. Data Preparation To ensure the accuracy and reliability of the data, two independent raters blind to subject groups manually reviewed the raw acceleration data for all testing sessions. Using a custom MATLAB code, any artifacts, such as sudden movements (e.g. talking, coughing, sneezing, dozing off, shift in gaze) or disruptions unrelated to standing balance, were identified and clipped from the data. This process ensured that the data used in the analysis represented actual standing balance performance, free from external noise or artifacts. A total of 1.94% of entire dataset was clipped due to the occurrence of artifacts in the recordings. Outliers were identified and removed from the dataset to avoid their influence on the analysis. Using the Explore option in SPSS, outliers were flagged based on extreme values in the positive or negative direction for each day, condition, and group. SPSS identifies outliers by calculating values that fall beyond 1.5 times the interquartile range (IQR) from the first or third quartile. Additionally, cases were excluded if sensor errors occurred during data collection (39 out of 7467, 0.005%). Statistical Tests All statistical tests were analyzed using IBM SPSS (v28.0.1.0, IBM Corp., 2021, Armonk, NY) with an alpha level of 0.05 for the statistical significance threshold of all testing. A formal a prori sample size calculation was not performed prior to data collection. Given there is no previous study of this sort to base a sample size calculation off, we instead determined our sample size based on feasibility constraints, including capacity and available resources. The dependent variables extracted were the participants' degree of postural instability measured using the magnitude of phybrata power (Phybrata Power=(X 2 + Y 2 + Z 2 )*1.3*0.01*9.81 2 ) to calculate the movement of the head regardless of direction according to Grafton et al. (2019) [ 38 ]. Data was normalized across the study to each individual's initial day performance, which expresses relative change from baseline and accounts for large inter-subject differences in baseline balance performance. To determine the therapeutic efficacy of repeated EVS sessions, phybrata power was analyzed using a linear mixed model analysis with subjects as the random factor, and group (Stimulation or Sham), session (Day 1 to 18), and interaction of group and day as fixed factors. Pairwise comparisons were used to compare Day 1’s performance to the subsequent days. A linear mixed model is best suited for this data analysis because it can compare data across multiple time points and handle missing data. Regression analyses were conducted to examine the relationship between Day 1 performance and change in performance across all conditions, with the Stimulation and Sham group analyzed separately. The questionnaire data was analyzed using regressions to explore the relationship between change in performance in Floor EC compared to SDMT scores, and Day 1 Floor EC performance against PRE ABC scores. Age and PASE scores were also evaluated as a predictor of SDMT, PRE ABC, and Day 1 Floor EC scores. T-tests were used to assess changes and differences between groups. Paired t-tests compared PRE ABC and POST ABC for both groups. Independent t-tests were performed to compare headache frequency between both groups. The effectiveness of the single-blind study design was tested with crosstabulation using a chi-squared test to determine if the distribution of correct and incorrect guesses was different from random guessing for both groups. Results Participants were recruited between October 2022 and November 2023 from retirement homes, assisted living facilities and community around the University of Calgary. Out of the 48 participants initially enrolled in the study, only those who completed all testing sessions were included in the final analysis. This criterion resulted in a total of 40 participants (14 males and 26 females) (19 Sham, 21 Stimulation) whose data were analyzed. Participants who were unable to complete the foam testing were excluded, which accounted for the removal of 8 participants (5 Sham, 3 Stimulation). This approach ensured consistency across participants for all conditions and testing days. See Fig. 3 for CONSORT flow diagram of how participants flowed through the study. The sample from 40 older adults had a mean age of 77.7 ± 11.8 years, height: 167.8 ± 10.8 cm, and weight: 70.7 ± 14.0 kg. The study was completed as originally intended, with all planned assessments and follow-ups carried out as per the protocol. No adverse effects of the intervention were reported. Retention Participant retention diminished after the 6-week intervention. Of the 40 participants 27 completed the 3-month follow-up and 30 completed the 6-month follow-up. If a participant was unable to attend a scheduled follow-up, they were still permitted to complete later follow-ups as their schedule allowed. Blindness Of the 15 participants assigned to the Sham group and retained to the 6-month follow-up session, 53.3% (n = 8) correctly identified their group, while 46.7% (n = 7) incorrectly thought they were in the Stimulation group. Conversely, of the 18 participants in the Stimulation group, 72.2% (n = 13) correctly identified their group, while 27.8% (n = 5) thought they were in the Sham group. A chi-square test was performed to assess whether participants' perceptions of their group assignment were associated with their actual group assignment. The test was not statistically significant, χ²(1, N = 33) = 2.238, p = 0.135, indicating no evidence of an association between group assignment and perceived group. EVS Reduces Sway in Older Adults Compared to Controls See Table 1 for mean +/- SD for each group in the linear mixed model (LMM). In the LMM analysis, significant main effects of group were observed in Floor EC (F(1,635) = 19.427, p < .001), Foam EO (F(1,599) = 23.701, p < .001), and Foam EC (F(1,610) = 17.560, p < .001) conditions, indicating differences between the Stimulation and Sham groups across conditions. Significant main effect of day was observed in the Foam EO (F(17,599) = 3.148, p < .001) and Foam EC (F(17,610) = 3.947, p < .001) conditions suggesting changes in performance over time. No significant interaction effects (group * day) were observed for any condition, including Floor EO (F(17,616) = 0.244, p = .999), Floor EC (F(17,635) = 0.692, p = .813), Foam EO (F(17,599) = 0.969, p = .492), Foam EC (F(17,610) = 0.537, p = .935). These results indicate that the Stimulation group improved more than the Sham group, however, both groups demonstrated improvements across testing sessions. Figure 4 shows the times series for Floor EO, Floor EC, Foam EO, and Foam EC for the Stimulation and Sham groups. Table 1. Mean ± (SD) phybrata power values for Stimulation and Sham groups across balance conditions (Floor EO, Floor EC, Foam EO, and Foam EC) measured on Days 1–18, 3-month, and 6-month follow-ups. Table 1 (Additional File 1) Note Values are reported as the mean ± standard deviation (SD). N represents the total sample size for each condition, while n represents the number of data points included after outlier removal. "Floor EO" refers to phybrata power measured during the Floor Eyes Open condition, "Floor EC" refers to Floor Eyes Closed, "Foam EO" refers to Foam Eyes Open, and "Foam EC" refers to Foam Eyes Closed. Day 1 values are normalized to a value of 1.00, and subsequent values represent performance relative to Day 1. Negative deviations indicate improved performance relative to baseline. Significance set to 0.05. Pairwise Comparisons Table 2 shows p-values of pairwise comparisons of subsequent days to Day 1 with an asterisk denoting significance. Pairwise comparisons for the Floor EO condition of all days compared to Day 1 show no significant differences for both the Stimulation and Sham groups (all p > 0.05). In the Floor EC condition, the Sham group exhibited no significant differences in performance across all pairwise comparisons with Day 1 (all p > 0.05), suggesting no meaningful change over time. Conversely, the Stimulation group demonstrated significant reductions in normalized phybrata power starting on Day 5 compared to Day 1 (Mean Diff. = -0.180, p = 0.03), with progressively larger reduction observed through Day 18 (Mean Diff = -0.302, p < 0.001). By the 6-month follow up, the reduction in normalized phybrata power diminished slightly (Mean Diff = -0.149, p = 0.092). In the Foam EO condition, the Sham group exhibited minimal changes in performance relative to Day 1, with significant improvements in normalized phybrata power observed on Day 14 (Mean Diff = -0.229, p = 0.036), and Day 16 (Mean Diff = -0.268, p = 0.018). In contrast, the Stimulation group displayed earlier and more consistent improvements in normalized phybrata power, with significant reductions first observed on Day 12 (Mean Diff = -0.216, p = 0.034). These significant improvements persisted through Day 18 (Mean Diff = -0.208, p = 0.043). In the Foam EC condition, the Sham group exhibited significant improvements compared to Day 1 performance starting on Day 13 and persisting through Day 18 except for Day 16 (p = 0.051). The Stimulation group demonstrated earlier and more sustained improvements in normalized phybrata power, with significant differences starting at Day 3 (Mean Diff = -0.219, p = 0.006) and persisting through the 6-month follow-up (Mean Diff = -0.456, p < 0.001). Table 2 P-values for pairwise comparisons of phybrata power relative to Day 1 for Stimulation and Sham groups across balance conditions (Floor EO, Floor EC, Foam EO, and Foam EC) on Days 2–18, 3-month, and 6-month follow-ups. Day (vs Day 1) Floor EO Floor EC Foam EO Foam EC Sham Stim Sham Stim Sham Stim Sham Stim 2 0.673 0.979 0.844 0.273 0.658 0.317 0.946 0.403 3 0.835 0.516 0.589 0.348 0.436 0.277 0.243 0.006* 4 0.302 0.646 0.445 0.240 0.464 0.131 0.694 0.005* 5 0.244 0.370 0.162 0.030* 0.784 0.193 0.115 < 0.001* 6 0.303 0.394 0.275 0.028* 0.651 0.071 0.205 < 0.001* 7 0.978 0.878 0.354 0.128 0.814 0.160 0.220 0.012* 8 0.889 0.411 0.245 0.012* 0.056 0.153 0.259 < 0.001* 9 0.291 0.869 0.287 0.011* 0.057 0.351 0.108 < 0.001* 10 0.123 0.952 0.210 0.039* 0.568 0.055 0.122 < 0.001* 11 0.297 0.615 0.206 0.086 0.086 0.078 0.496 < 0.001* 12 0.974 0.710 0.107 0.004* 0.133 0.034* 0.067 0.010* 13 0.281 0.425 0.677 0.002* 0.091 0.040* 0.017* < 0.001* 14 0.661 0.673 0.675 0.002* 0.036* < 0.001* 0.046* < 0.001* 15 0.251 0.936 0.252 0.004* 0.072 0.048* 0.017* < 0.001* 16 0.149 0.538 0.558 0.007* 0.018* 0.016* 0.051 < 0.001* 17 0.454 0.555 0.537 < 0.001* 0.176 0.01* 0.025* < 0.001* 18 0.523 0.253 0.270 < 0.001* 0.471 0.043* 0.023* < 0.001* 3M 0.704 0.428 0.711 0.007* 0.146 0.230 0.062 0.001* 6M 0.678 0.608 0.759 0.092 0.240 0.051 0.923 < 0.001* Note. Asterisks (*) denote significant differences relative to Day 1 with α = 0.05 level. P-values indicate the results of pairwise comparisons for each group (Stimulation and Sham) and condition. Days are listed chronologically (Day 2–18, 3-month [3M], and 6-month [6M]) for consistency across conditions. Regression Analysis For Floor EC, initial (baseline) performance significantly predicted change in performance for the Stimulation group (F (1, 19) = 97.40, p < 0.001, R² = 0.837). Baseline scores negatively predicted improvement (B = -0.716, p < 0.001), indicating that participants with poorer initial balance improved the most. The Sham group did not demonstrate a significant relationship (F (1, 17) = 0.105, p = 0.750, R² = 0.006). In Foam EO, significant relationships were observed for both Stimulation groups (F(1, 18) = 142.02, p < 0.001, R² = 0.888) and Sham (F(1, 16) = 16.66, p < 0.001, R² = 0.510), with larger baseline balance impairments predicting larger balance improvements (B = -0.648, p < 0.001 for Stimulation; B = -0.407, p < 0.001 for Sham). In the Foam EC condition, baseline performance was a significant predictor of change in performance for only the Stimulation group (F(1,19) = 22.87, p < 0.001, R 2 = 0.546) with larger Day 1 balance impairments again predicting greater balance improvements (B = -0.432, p < 0.001), while the Sham group did not exhibit a significant relationship (F(1,15 = 1.03, p = 0.326, R² = 0.254, B = -0.147). Figure 4 shows scatterplots of the Floor EC, Foam EO, and Foam EC Day 1 performance vs change in performance. Questionnaire Analysis An independent t-test comparing headache frequency between the Stimulation and Sham groups found no significant difference (p = 0.473) throughout the 6-week intervention. There were no significant differences in MIDAS scores from pre- to post-intervention for the Stimulation group (p = 0.302) and the Sham group (p = 0.363). There was a significant increase in balance confidence scores from pre- to post-intervention in both the Stimulation (p = 0.023) and Sham groups (p = 0.019). In the Sham group, regression analysis revealed a significant relationship between Physical Activity Scale for the Elderly (PASE) scores and changes in phybrata power in the Floor EC condition (F(1,12) = 7.019, p = 0.021, R 2 = 0.369). Higher physical activity levels were associated with smaller improvements in phybrata power (i.e., less reduction in phybrata power). PASE scores accounted for 36.9% of the variance in the change in phybrata power. While the Stimulation groups regression analysis revealed no significant relationship (R = 0.208, F(1,17) = 0.767, p = 0.393, R 2 = 0.043), with PASE scores explaining 4.3% of the variance. This was not significant for the Foam EO and Foam EC conditions for both groups. A significant negative correlation was observed between PRE ABC scores and baseline performance in the Floor EC condition (r = -0.652, p < 0.001), indicating that participants with higher balance confidence exhibited lower phybrata power. A strong negative correlation was identified between age and SDMT scores (r = -0.799, p < 0.001), demonstrating that older participants exhibited lower cognitive performance. Age was also negatively correlated with balance confidence (r = -0.545, p < 0.001), suggesting that older participants reported lower confidence in performing balance-related tasks. There were no significant relationships between SDMT scores and balance performance. Discussion This study demonstrates that cumulative EVS dosing is a novel and effective therapeutic approach for improving balance in older adults. Compared to the Sham group, which showed no significant improvement from baseline to the end of the intervention for all condition except Foam EC, the Stimulation group exhibited substantial and sustained reductions in phybrata power across challenging sensory conditions. These findings provide evidence that the observed improvements in the EVS group are likely not attributable to natural learning effects or practice but instead reflect the efficacy of the intervention. The lack of significant improvements in simpler tasks, such as the Floor EO condition, suggests that EVS is most effective under conditions requiring greater reliance on vestibular and proprioceptive inputs, where sensory integration plays a critical role. The results from the foam conditions highlight the cumulative impact of repeated EVS dosing. Significant reductions in phybrata power in the Stimulation group began as early as Day 12 in the Floor EC condition and Day 3 in the Foam EC condition, with these improvements persisting to the three month follow up (floor EC) and six month follow up (foam EC). In contrast, the Sham group displayed delayed and inconsistent improvements, emphasizing the role of EVS in driving these outcomes. Together, these findings establish EVS as a minimally invasive, portable, and promising intervention for addressing balance deficits in aging populations. Potential Peripheral Mechanisms The improvements in balance observed in this study could be attributed to peripheral mechanisms of EVS. Vestibular afferents, which transmit signals from the vestibular sensory organs to the brain, are crucial for maintaining postural stability. Prior research supports the idea that EVS directly influences vestibular afferent activity, enhancing the processing of vestibular signals necessary for balance control. For instance, Goldberg et al. (1984) demonstrated that intra-vestibule EVS modulates vestibular afferent firing, specifically from the otolith organs and semicircular canals. This finding suggests that EVS enhances the input generation of peripheral vestibular signals to the vestibular nuclei, thereby improving postural stability during challenging balance tasks [ 39 ]. The findings from Kwan et al. (2019) further reinforce this notion by showing that transcranial EVS activates both semicircular canal and otolith afferents in nonhuman primates [ 22 ]. This balanced activation of vestibular afferents may account for the improvements in sensory integration observed in participants performing tasks that rely heavily on vestibular and proprioceptive inputs, such as the Floor EC and Foam EC conditions. By increasing the sensitivity of vestibular afferents to subthreshold signals, EVS likely enhances the neural inputs that enable detection of subtle head movements to maintain postural stability. Additionally, it is proposed that EVS-induced improvements in postural stability may be driven by stochastic resonance, a phenomenon in which noise added to a system enhances signal detection [ 40 ], but this only occurs during stimulation, and cannot account for the persistent effects observed here with repeated EVS exposure. The cumulative effects of EVS dosing may amplify vestibular afferent inputs, leading to pronounced improvements in vestibular balance control. Participants in the Stimulation group showed significant reductions in phybrata power as early as Day 3 in the Foam EC condition, showing the rapid impact of EVS on peripheral vestibular processing. Age-related changes in vestibular hair cell density and function may further explain the effectiveness of EVS in older adults. EVS not only stimulates vestibular afferents but may also influence vestibular hair cells [ 41 ]. Although the capacity for vestibular hair cell regeneration in humans is limited, immature hair bundles in the utricular epithelia of adults over 60 years old [ 11 ]. These findings imply that the vestibular epithelia retain some capacity for regeneration throughout life, via either direct trans-differentiation of supporting cells into hair cells or by supporting cell division and asymmetric differentiation, where one daughter cell trans-differentiates into a hair cell and the other remains as a supporting cell [ 42 ]. EVS may stimulate these immature hair bundles, potentially supporting functional recovery of vestibular sensory cells. Further research is required to validate whether EVS directly facilitates hair cell regeneration or if its effects are limited to afferent stimulation. The modulation of afferent firing by EVS may also address the age-related decline in vestibular sensitivity. Vestibular hair cell loss contributes to reduced sensory input in older adults, leading to balance impairments [ 10 ]. By enhancing vestibular afferent sensitivity and potentially stimulating remaining hair cells, EVS could compensate for this sensory loss, allowing older adults to maintain or improve postural stability under challenging conditions. Potential Central Mechanisms The potential central mechanisms underlying the improvements in balance observed in this study may involve neuroplasticity within the vestibular nuclei and associated neural pathways. The vestibular nuclei are critical for processing sensory inputs from the vestibular system and integrating these signals with proprioceptive and visual information to maintain postural control. Neuroplasticity within these nuclei may play a key role in the sustained balance improvements observed in participants receiving EVS. Evidence from previous studies supports the potential for long-term potentiation (LTP) within the vestibular nuclei, a neural mechanism that enhances synaptic efficacy [ 43 ]. This finding aligns with the hypothesis that repeated EVS sessions may promote LTP in the vestibular nuclei, thereby improving the processing of vestibular inputs. Similarly, the vestibular nuclei's capacity for neuroplasticity, particularly following vestibular system stimulation or injury [ 44 ], [ 45 ]. These studies suggest that repeated EVS exposure may facilitate functional changes in the vestibular nuclei, enhancing their ability to process and respond to sensory inputs. Vestibular neuroplasticity, specifically synaptic plasticity within the vestibular nuclei, may account for the prolonged balance improvements observed following nEVS [ 25 ]. Significant post-stimulation effects lasting several hours have been observed in healthy older adults, supporting the idea that nEVS induces neuroplastic changes in the central vestibular pathways [ 25 ]. This aligns with our study's findings, where participants in the Stimulation group exhibited sustained improvements in phybrata power in the Foam EC condition, with effects persisting through the 6-month follow-up. The extended duration of these improvements suggests that cumulative nEVS may induce long-lasting neuroplastic changes in the central vestibular system. Additionally, the cerebellum, which is closely linked to the vestibular nuclei, likely contributes to the observed effects. The cerebellum plays a crucial role in fine-tuning motor control and balance by integrating sensory inputs and coordinating motor responses. Neuroplasticity within the cerebellum, particularly in its connections with the vestibular nuclei, may enhance the central processing of vestibular inputs. nEVS can activate cortical areas beyond the vestibular nuclei, including regions associated with motor planning and balance control [ 46 ]. While our study employed subthreshold nEVS levels that were unlikely to evoke direct cortical activation, the observed improvements suggest that repeated dosing may strengthen vestibular pathways. Age-related reductions in vestibular nuclei neurons and cerebellar function may further highlight the importance of nEVS-induced neuroplasticity in older adults. Aging leads to neuronal loss in the vestibular nuclei, contributing to declines in balance performance [ 10 ], [ 47 ]. nEVS may counteract these effects by enhancing synaptic efficacy and promoting neuroplastic changes within central pathways, allowing older adults to maintain or improve postural stability. In addition to enhancing balance, nEVS may also have broader implications for central neural function. Higher EVS input levels activate cortical areas involved in visual and motor integration, suggesting that repeated dosing could improve sensory integration and motor planning [ 46 ]. While our study focused on subthreshold stimulation, future research should investigate whether higher EVS intensities could amplify these central effects. Clinical Significance This study demonstrates that nEVS is a promising therapeutic tool for improving balance in older adults, particularly in conditions that rely heavily on vestibular and proprioceptive inputs. Improvements observed in the Stimulation group, especially in the Foam EC and Foam EO conditions, emphasize its utility in targeting sensory integration processes critical for postural stability. Peripheral vestibular deficits are prevalent among older populations and exacerbate age-related declines in balance, further underlining the clinical need for interventions that enhance vestibular function [ 10 ]. High fall-risk individuals identified through the Sensory Organization Test commonly displayed vestibular deficits [ 48 ]. This suggests that interventions like EVS, which target vestibular system enhancement, may have the greatest impact on individuals with greater baseline impairments. Tailoring EVS treatment based on individual vestibular thresholds could further optimize its effectiveness. While nEVS has been shown to induce short-term balance enhancements, the retention of these effects was poor [ 25 ]. However, with cumulative dosing treatments, retention was observed up to six months post-stimulation, suggesting neuroplastic changes and the potential to transition individuals from high- to low-risk profiles over 18 sessions. The safety and tolerability of EVS as an intervention were further supported by the absence of significant differences in headache frequency or MIDAS scores between the Stimulation and Sham groups, indicating that the intervention does not induce notable headaches or migraines. Additionally, there were no other adverse effects to report with the stimulation used in this study. Both groups demonstrated significant improvements in balance confidence scores (PRE ABC vs. POST ABC), aligning with the reductions in phybrata power and suggesting that EVS not only enhances physical balance but also positively impacts participants' confidence in their ability to perform balance-related tasks. A significant negative correlation between PRE ABC scores and baseline phybrata power in the Floor EC condition indicates that individuals with higher balance confidence exhibited lower phybrata power (better performance) at baseline. Additionally, the relationship between PRE ABC scores and age highlights the importance of addressing age-related declines in both physical and psychological aspects of balance. Similarly, the strong negative correlation between SDMT scores and age highlight age-related cognitive decline, yet the lack of a relationship between SDMT scores and changes in phybrata power during the intervention suggests that EVS-induced balance improvements were independent of participants' cognitive performance. This finding highlights EVS as a targeted intervention for physical balance deficits rather than cognitive impairments. However, future studies should look at the relationship with EVS to help with learning and spatial awareness. The PASE results further emphasize the robustness of the EVS intervention. While higher PASE scores (indicative of greater baseline physical activity) were associated with smaller improvements in phybrata power in the Sham group, no significant relationship was observed in the Stimulation group in the Floor EC condition. This suggests that EVS provides balance improvements regardless of participants' baseline physical activity levels. In contrast, the Sham group’s dependency on PASE scores highlights the role of natural learning effects or activity-related benefits in driving improvements. The independence of the Stimulation group from PASE-related effects demonstrates that nEVS works consistently, making it an accessible and scalable therapeutic option for a broader range of older adults, irrespective of their activity levels. Since EVS stimulates a cranial nerve, it has been explored for potential improvements in anxiety, memory, and cognition [ 24 ]. Participants undergoing EVS dosing can easily incorporate additional therapies tailored to their needs or combine them with balance exercises to further enhance balance improvements. This versatility enhances EVS both as a standalone treatment and as a complementary component of a holistic therapeutic strategy aimed at improving balance and reducing fall risk in vulnerable populations. EVS has proven to be an effective treatment for improving standing balance in older adults. It is easy to use, portable, low-cost, and minimally invasive, making it a valuable tool to counteract age-related decline. Participants in this study reported no adverse side effects, aligning with findings from subthreshold EVS studies [ 49 ]. However, it is noteworthy that suprathreshold EVS (> 1 mA) may induce more pronounced side effects, such as vertigo and metallic taste [ 50 ]. The portability of EVS, combined with a head-mounted accelerometer, facilitates seamless balance assessments and treatments, enabling integration into various settings, including retirement homes, for real-world data collection. Limitations This study has several limitations. First, no a priori sample size calculation was performed, making it unclear whether the initial proof of concept study would be adequately powered to detect effects. However, this paper will serve for proper sample size calculations to ensure future studies can adequately power their experiments. Second, the single-blind design was chosen due to the subthreshold intensity of the stimulus. However, to assess the effectiveness of blinding, participants were asked to guess what their group assignment was, and the distribution of guesses was not significantly different from random guessing suggesting successful blinding. The manual data cleaning process included removing artifacts of talking, head shaking, sneezing, or other anomalous movements which removed 1.94% of the total data. In future studies, a machine learning algorithm could be developed to clean the dataset, reducing potential biases from human error. Additionally, while the study demonstrated significant balance improvements in challenging sensory conditions (e.g., Foam EC), the generalizability of these findings to broader populations remains uncertain. The participants were older adults, and the effects of EVS in individuals with more severe balance deficits, vestibular dysfunction, or neurological conditions need further exploration. However, given participants with the poorest balance initial performance showed the largest improvement, we suggest that EVS will be effective in clinical populations with more severe balance deficits. Lastly, while the current study focused on static balance, assessing dynamic balance and gait stability would provide a more comprehensive understanding of EVS’s impact on mobility, quality of life, and fall prevention. Conclusion This study provides evidence that cumulative EVS is a novel, effective intervention for improving balance in older adults. Through a comprehensive evaluation of balance performance across multiple sensory conditions, we demonstrated significant and sustained improvements in postural control, particularly in challenging conditions that increase reliance on vestibular inputs, such as Floor EC, Foam EO, and Foam EC. The results emphasize the capacity of EVS to enhance sensory reweighting and facilitate neuroplastic changes, leading to improved balance stability and confidence. By showing that participants with poorer baseline performance achieved greater improvements, this study highlights the potential of EVS to target high-risk individuals, reducing fall risk and addressing age-related vestibular decline. These findings also support the hypothesis that EVS enhances both peripheral and central vestibular processing, which may underlie the observed improvements in postural control. Additionally, the portability and scalability of EVS make it an attractive option for community and clinical use, from retirement homes to outpatient rehabilitation clinics. Abbreviations ABC – Activities-specific Balance Confidence Scale CNS – Central Nervous System EO – Eyes Open EC – Eyes Closed EVS – Electrical Vestibular Stimulation IMU – Inertial Measurement Unit IQR – Interquartile Range LMM -Linear Mixed Model mCTSIB – Modified Clinical Test of Sensory Interaction on Balance MIDAS – Migraine Disability Assessment Scale nEVS – Noisy Electrical Vestibular Stimulation PASE – Physical Activity Scale for the Elderly SDMT – Symbol Digit Modalities Test VRT – Vestibular Rehabilitation Therapy Declarations Ethics approval and consent to participate. All procedures were approved by the University of Calgary Conjoint Health Research Ethics Board (Ethics ID: REB22-1006) and retrospectively registered as a clinical trial on February 25, 2025 (NCT06846047). All participants provided written informed consent before participation. Consent for publication. The authors give consent for publication. Availability of data and materials . The dataset supporting the findings of this study is publicly available via Borealis: King, Jordan, 2025, Replication Data for: Electrical vestibular stimulation to improve static balance in older adults: a randomized control trial, https://doi.org/10.5683/SP3/SWWBUR, Borealis, DRAFT VERSION. Competing interests. The authors have no competing interests. Funding. This research was funded by Natural Sciences and Engineering Research Council Discovery (RGPIN-2020-06068) and Idea-to-Innovation grants (I2IPJ 548811-2020), as well as a New Frontiers in Research Fund grant (NFRFR-2021-00199) awarded to RMP . JAK was funded by the Hotchkiss Brain Institute (HBI) Harley N. Hotchkiss Graduate Scholarship in Neuroscience. Neursantys contributed funding for research assistants, participation awards, and parking expenses. Authors' contributions. JAK, JDR, and RMP was involved in all stages of the project including study design, data collection, analysis, interpretation, and manuscript writing. NW, NR, JAB, NM, AC, SC, EF, and RMP assisted with data collection. Data analysis was conducted by JAK, NR, AC, and MS. Manuscript preparation was done by JAK and NW. The final manuscript was reviewed and edited by SLO, JDR, JR, and RMP. All authors read and approved the final manuscript. Acknowledgements. The authors would like to acknowledge United Active Living Fish Creek, United Active Living Garrison Green, and Verve The Lodge for permitting data collection at their retirement and assisted living communities. Special thanks to all participants for their dedication throughout the 7.5-month protocol, and to the undergraduate research assistants who contributed significantly to data collection. References Public Health Agency of Canada. Seniors’ falls in Canada. Second report, Public Health Agency of Canada, Ottawa, ON, 2014. Accessed: Aug. 09, 2024. [Online]. Available: https://www.canada.ca/en/public-health/services/publications/healthy-living/seniors-falls-canada-second-report.html Public Health Agency of Canada. Surveillance Report on Falls Among Older Adults in Canada, Public Health Agency of Canada, Ottawa, Ontario, Canada, HP35-154/2022E-PDF, Mar. 2022. Iwasaki S, Yamasoba T. Dizziness and Imbalance in the Elderly: Age-related Decline in the Vestibular System. Aging Dis. 2015;6(1):38. 10.14336/AD.2014.0128 . Baloh RW, et al. Comparison of Static and Dynamic Posturography in Young and Older Normal People. J Am Geriatr Soc. Apr. 1994;42(4):405–12. 10.1111/j.1532-5415.1994.tb07489.x . Parachute. Cost of Injury in Canada 2021, Oct. 2024. Accessed: Jan. 15, 2025. [Online]. Available: https://parachute.ca/en/professional-resource/cost-of-injury-in-canada/ World Health Organization. Ageing and health. Oct. 2024. Brosel S, Strupp M. The Vestibular System and Ageing, in Biochemistry and Cell Biology of Ageing: Part II Clinical Science , vol. 91, J. R. Harris and V. I. Korolchuk, Eds., in Subcellular Biochemistry, vol. 91., Singapore: Springer Singapore, 2019, pp. 195–225. 10.1007/978-981-13-3681-2_8 Baloh RW, Spain S, Socotch TM, Jacobson KM, Bell T. Posturography and Balance Problems in Older People. J Am Geriatr Soc. Jun. 1995;43:638–44. 10.1111/j.1532-5415.1995.tb07198.x . Rossignol S, Dubuc R, Gossard J-P. Dynamic Sensorimotor Interactions in Locomotion, Physiol. Rev. , vol. 86, no. 1, pp. 89–154, Jan. 2006, 10.1152/physrev.00028.2005 Zalewski C. Aging of the Human Vestibular System. Semin Hear. Jul. 2015;36(03):175–96. 10.1055/s-0035-1555120 . Taylor RR et al. Jun., Characterizing human vestibular sensory epithelia for experimental studies: new hair bundles on old tissue and implications for therapeutic interventions in ageing, Neurobiol. Aging , vol. 36, no. 6, pp. 2068–2084, 2015, 10.1016/j.neurobiolaging.2015.02.013 Jahn K. Inverse U-shaped curve for age dependency of torsional eye movement responses to galvanic vestibular stimulation. Brain. Apr. 2003;126(7):1579–89. 10.1093/brain/awg163 . Dalton BH, Blouin J-S, Allen MD, Rice CL, Inglis JT. The altered vestibular-evoked myogenic and whole-body postural responses in old men during standing. Exp Gerontol. Dec. 2014;60:120–8. 10.1016/j.exger.2014.09.020 . Peters RM, Blouin J-S, Dalton BH, Inglis JT. Older adults demonstrate superior vestibular perception for virtual rotations. Exp Gerontol. Sep. 2016;82:50–7. 10.1016/j.exger.2016.05.014 . Baloh RW, Jacobson KM, Socotch TM. The effect of aging on visual-vestibuloocular responses. Exp Brain Res. Aug. 1993;95(3). 10.1007/BF00227144 . Han BI, Song HS, Kim JS. Vestibular Rehabilitation Therapy: Review of Indications, Mechanisms, and Key Exercises. J Clin Neurol. 2011;7(4):184. 10.3988/jcn.2011.7.4.184 . Haxby F, Akrami M, Zamani R. Finding a Balance: A Systematic Review of the Biomechanical Effects of Vestibular Prostheses on Stability in Humans. J Funct Morphol Kinesiol. Mar. 2020;5(2):23. 10.3390/jfmk5020023 . Dlugaiczyk J, Gensberger KD, Straka H. Galvanic vestibular stimulation: from basic concepts to clinical applications, J. Neurophysiol. , vol. 121, no. 6, pp. 2237–2255, Jun. 2019, 10.1152/jn.00035.2019 Herssens N, McCrum C. Stimulating balance: recent advances in vestibular stimulation for balance and gait. J Neurophysiol. Aug. 2019;122(2):447–50. 10.1152/jn.00851.2018 . White O, Babič J, Trenado C, Johannsen L, Goswami N. The Promise of Stochastic Resonance in Falls Prevention. Front Physiol. Jan. 2019;9:1865. 10.3389/fphys.2018.01865 . Lajoie K, Marigold DS, Valdés BA, Menon C. The potential of noisy galvanic vestibular stimulation for optimizing and assisting human performance. Neuropsychologia. Feb. 2021;152:107751. 10.1016/j.neuropsychologia.2021.107751 . Kwan A, Forbes PA, Mitchell DE, Blouin J-S, Cullen KE. Neural substrates, dynamics and thresholds of galvanic vestibular stimulation in the behaving primate, Nat. Commun. , vol. 10, no. 1, p. 1904, Apr. 2019. 10.1038/s41467-019-09738-1 Lopez C, Cullen KE. Electrical stimulation of the peripheral and central vestibular system, Curr. Opin. Neurol. , vol. 37, no. 1, pp. 40–51, Feb. 2024, 10.1097/WCO.0000000000001228 de Pires APB, Silva TR, Torres MS, Diniz ML, Tavares MC, Gonçalves DU. Galvanic vestibular stimulation and its applications: a systematic review, Brazilian Journal of Otorhinolaryngology , vol. 88. Elsevier Editora Ltda, pp. S202–S211, Nov. 2022. 10.1016/j.bjorl.2022.05.010 Fujimoto C, et al. Noisy galvanic vestibular stimulation induces a sustained improvement in body balance in elderly adults. Sci Rep. Nov. 2016;6(1):37575. 10.1038/srep37575 . Agrawal Y, Carey JP, Della Santina CC, Schubert MC, Minor LB. Disorders of Balance and Vestibular Function in US Adults: Data From the National Health and Nutrition Examination Survey, 2001–2004. Arch Intern Med. May 2009;169(10):938. 10.1001/archinternmed.2009.66 . Inukai Y, et al. Effect of noisy galvanic vestibular stimulation in community-dwelling elderly people: a randomised controlled trial. J Neuroeng Rehabil. Dec. 2018;15(1):63. 10.1186/s12984-018-0407-6 . Agrawal Y, Carey JP, Hoffman HJ, Sklare DA, Schubert MC, The Modified Romberg Balance Test: Normative Data in, Adults US. Otol. Neurotol. , vol. 32, no. 8, pp. 1309–1311, Oct. 2011, 10.1097/MAO.0b013e31822e5bee Cohen HS et al. Jun., Screening for Vestibular Disorders Using the Modified Clinical Test of Sensory Interaction and Balance and Tandem Walking With Eyes Closed, Otol. Neurotol. , vol. 40, no. 5, pp. 658–665, 2019, 10.1097/MAO.0000000000002173 Nguyen TT, Kang J-J, Oh S-Y. Thresholds for vestibular and cutaneous perception and oculomotor response induced by galvanic vestibular stimulation. Front Neurol. Aug. 2022;13:955088. 10.3389/fneur.2022.955088 . Inukai Y, et al. Effect of noisy galvanic vestibular stimulation in community-dwelling elderly people: a randomised controlled trial. J Neuroeng Rehabil. Dec. 2018;15(1):63. 10.1186/s12984-018-0407-6 . Ralston JD, Raina A, Benson BW, Peters RM, Roper JM, Ralston AB. Physiological Vibration Acceleration (Phybrata) Sensor Assessment of Multi-System Physiological Impairments and Sensory Reweighting Following Concussion, Med. Devices Evid. Res. , vol. Volume 13, pp. 411–438, Dec. 2020, 10.2147/MDER.S279521 Abdollah V, Dief TN, Ralston J, Ho C, Rouhani H. Investigating the validity of a single tri-axial accelerometer mounted on the head for monitoring the activities of daily living and the timed-up and go test, Gait Posture , vol. 90, pp. 137–140, Oct. 2021, 10.1016/j.gaitpost.2021.08.020 Filiatrault J, et al. Evidence of the Psychometric Qualities of a Simplified Version of the Activities-specific Balance Confidence Scale for Community-Dwelling Seniors. Arch Phys Med Rehabil. May 2007;88(5):664–72. 10.1016/j.apmr.2007.02.003 . Carone D, Sherman A, Sep. Compendium of Neuropsychological Tests. : Fundamentals of neuropsychological assessment and test reviews for clinical practice (4th ed.), Appl. Neuropsychol. Adult , vol. 31, pp. 1–4, 2023, 10.1080/23279095.2023.2260143 Washburn RA, Smith KW, Jette AM, Janney CA. The physical activity scale for the elderly (PASE): Development and evaluation, J. Clin. Epidemiol. , vol. 46, no. 2, pp. 153–162, Feb. 1993, 10.1016/0895-4356(93)90053-4 Stewart WF, et al. An international study to assess reliability of the Migraine Disability Assessment (MIDAS) score. Neurology. 1999;53(5):988–988. 10.1212/WNL.53.5.988 . Grafton ST, Ralston AB, Ralston JD. Monitoring of postural sway with a head-mounted wearable device: effects of gender, participant state, and concussion. Med Devices Evid Res. May 2019;12:151–64. 10.2147/MDER.S205357 . Goldberg JM, Smith CE, Fernandez C. Relation between discharge regularity and responses to externally applied galvanic currents in vestibular nerve afferents of the squirrel monkey, J. Neurophysiol. , vol. 51, no. 6, pp. 1236–1256, Jun. 1984, 10.1152/jn.1984.51.6.1236 Iwasaki S et al. Mar., Noisy vestibular stimulation improves body balance in bilateral vestibulopathy, Neurology , vol. 82, no. 11, pp. 969–975, 2014, 10.1212/WNL.0000000000000215 Gensberger KD, et al. Galvanic Vestibular Stimulation: Cellular Substrates and Response Patterns of Neurons in the Vestibulo-Ocular Network. J Neurosci. Aug. 2016;36:9097–110. 10.1523/JNEUROSCI.4239-15.2016 . Groves AK. The challenge of hair cell regeneration, Exp. Biol. Med. Maywood NJ , vol. 235, no. 4, pp. 434–446, Apr. 2010, 10.1258/ebm.2009.009281 Grassi S, Frondaroli A, Pettorossi VE. Different Metabotropic Glutamate Receptors Play Opposite Roles in Synaptic Plasticity of the Rat Medial Vestibular Nuclei, J. Physiol. , vol. 543, no. 3, pp. 795–806, Sep. 2002, 10.1113/jphysiol.2002.023424 Smith PF, Curthoys IS. following unilateral labyrinthectomy: a review. Dutia MB. Mechanisms of vestibular compensation: recent advances. Curr Opin Otolaryngol Head Neck Surg. Oct. 2010;18(5):420–4. 10.1097/MOO.0b013e32833de71f . Helmchen C, Rother M, Spliethoff P, Sprenger A. Increased brain responsivity to galvanic vestibular stimulation in bilateral vestibular failure. NeuroImage Clin. 2019;24:101942. 10.1016/j.nicl.2019.101942 . Alvarez JC et al. Apr., Aging and the human vestibular nuclei: morphometric analysis, Mech. Ageing Dev. , vol. 114, no. 3, pp. 149–172, 2000, 10.1016/S0047-6374(00)00098-1 Sung P, Rowland P. Impact of sensory reweighting strategies on postural control using the sensory organization test in older adults with and without fall risks, Physiother. Res. Int. , vol. 29, no. 2, p. e2075, Apr. 2024. 10.1002/pri.2075 Utz KS et al. Oct., Minor adverse effects of galvanic vestibular stimulation in persons with stroke and healthy individuals, Brain Inj. , vol. 25, no. 11, pp. 1058–1069, 2011, 10.3109/02699052.2011.607789 Cavin ID, Glover PM, Bowtell RW, Gowland PA. Thresholds for perceiving metallic taste at high magnetic field, J. Magn. Reson. Imaging , vol. 26, no. 5, pp. 1357–1361, Nov. 2007, 10.1002/jmri.21153 Tables Table 1 is available in the Supplementary Files section. Additional Declarations No competing interests reported. Supplementary Files AdditionalFile1.xls Cite Share Download PDF Status: Published Journal Publication published 31 Oct, 2025 Read the published version in Journal of NeuroEngineering and Rehabilitation → Version 1 posted Editorial decision: Revision requested 02 Jun, 2025 Reviews received at journal 30 May, 2025 Reviews received at journal 18 May, 2025 Reviews received at journal 14 May, 2025 Reviewers agreed at journal 05 May, 2025 Reviewers agreed at journal 01 May, 2025 Reviewers agreed at journal 24 Apr, 2025 Reviewers invited by journal 06 Apr, 2025 Editor assigned by journal 02 Apr, 2025 Submission checks completed at journal 02 Apr, 2025 First submitted to journal 01 Apr, 2025 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-6349795","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":458290880,"identity":"bcfae9c7-0e5c-403d-aae6-15aa27a3bd6f","order_by":0,"name":"Jordan A. King","email":"","orcid":"","institution":"University of Calgary","correspondingAuthor":false,"prefix":"","firstName":"Jordan","middleName":"A.","lastName":"King","suffix":""},{"id":458290881,"identity":"cf6af3dc-4ad7-4a25-be86-658af49fa5ad","order_by":1,"name":"Noah Walters","email":"","orcid":"","institution":"University of Calgary","correspondingAuthor":false,"prefix":"","firstName":"Noah","middleName":"","lastName":"Walters","suffix":""},{"id":458290882,"identity":"ab6c76e8-f29b-4c4b-8982-d535dd4acdd2","order_by":2,"name":"Nadine Rodrigues","email":"","orcid":"","institution":"University of Calgary","correspondingAuthor":false,"prefix":"","firstName":"Nadine","middleName":"","lastName":"Rodrigues","suffix":""},{"id":458290883,"identity":"d3a15b12-d739-41e4-8a98-2681536489fd","order_by":3,"name":"Jenna Al Bastami","email":"","orcid":"","institution":"University of Calgary","correspondingAuthor":false,"prefix":"","firstName":"Jenna","middleName":"Al","lastName":"Bastami","suffix":""},{"id":458290884,"identity":"6ad8cdab-d177-4120-b1bd-8046c8821fb6","order_by":4,"name":"Niki Mehri","email":"","orcid":"","institution":"University of Calgary","correspondingAuthor":false,"prefix":"","firstName":"Niki","middleName":"","lastName":"Mehri","suffix":""},{"id":458290885,"identity":"69a1236f-013b-42f8-8f5a-dfa15157b9b7","order_by":5,"name":"Adrian Chan","email":"","orcid":"","institution":"University of Calgary","correspondingAuthor":false,"prefix":"","firstName":"Adrian","middleName":"","lastName":"Chan","suffix":""},{"id":458290886,"identity":"67b13309-f58b-4378-a652-4ea2fc6b3afc","order_by":6,"name":"Madison Spencer","email":"","orcid":"","institution":"University of Calgary","correspondingAuthor":false,"prefix":"","firstName":"Madison","middleName":"","lastName":"Spencer","suffix":""},{"id":458290887,"identity":"7652b0ec-7484-4557-8211-095cf10169c1","order_by":7,"name":"Sadie Clark","email":"","orcid":"","institution":"University of Calgary","correspondingAuthor":false,"prefix":"","firstName":"Sadie","middleName":"","lastName":"Clark","suffix":""},{"id":458290888,"identity":"947db997-e437-4412-983b-0aa8a13f589a","order_by":8,"name":"Evan Ferrier","email":"","orcid":"","institution":"University of Calgary","correspondingAuthor":false,"prefix":"","firstName":"Evan","middleName":"","lastName":"Ferrier","suffix":""},{"id":458290889,"identity":"cdb0f9cc-0f4f-41fa-9293-6535fdbfaa50","order_by":9,"name":"Serena L. Orr","email":"","orcid":"","institution":"University of Calgary","correspondingAuthor":false,"prefix":"","firstName":"Serena","middleName":"L.","lastName":"Orr","suffix":""},{"id":458290890,"identity":"b3fbc1a4-9acf-4fa8-a2dc-d36ff3f8b3ef","order_by":10,"name":"Jocelyn Rempel","email":"","orcid":"","institution":"Mount Royal University","correspondingAuthor":false,"prefix":"","firstName":"Jocelyn","middleName":"","lastName":"Rempel","suffix":""},{"id":458290891,"identity":"a8e39f1c-477b-4526-9923-5afc2457d611","order_by":11,"name":"Andreas Hauenstein","email":"","orcid":"","institution":"Neursantys, Inc","correspondingAuthor":false,"prefix":"","firstName":"Andreas","middleName":"","lastName":"Hauenstein","suffix":""},{"id":458290892,"identity":"8a9a56f4-7b66-4fcb-961f-b89573a100d9","order_by":12,"name":"Josh Roper","email":"","orcid":"","institution":"Neursantys, Inc","correspondingAuthor":false,"prefix":"","firstName":"Josh","middleName":"","lastName":"Roper","suffix":""},{"id":458290893,"identity":"50985565-a208-4c1f-bb06-83934125fc02","order_by":13,"name":"John D. Ralston","email":"","orcid":"","institution":"Neursantys, Inc","correspondingAuthor":false,"prefix":"","firstName":"John","middleName":"D.","lastName":"Ralston","suffix":""},{"id":458290894,"identity":"6a689ca2-0b9e-4c27-a0e6-e968d8f0959c","order_by":14,"name":"Ryan M Peters","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAABDUlEQVRIie2RsUoDQRBAZw3kmsG1nKCQX9gQMAje3a/csZA0SSWEVJJqq0PbA+38BEFSbtjimsXa8kC4KkUkIOnixk5hJXaC+2CGYZjHDAxAIPDX0WuXjg+dJhdsWbrc/o3SMniIMihlU7PF5TU/rWoTq6Tb5g/NBiHp+pSzl+FAMDukzs1YmImSPUVN/w5B9ua+gyg7J6YMCYvgFM0U6X4LQTO/Mnp3yo5SG9XmQulUUbXZK6lfGe+3aBIIwrgiV7z43JJ7FVxNKbeyU1oUy+JZSkV4xe6FlF4lGj3R2yLhvIhe19tpEt/y6hFWsyT2KXCSAXy9gTI4QuGbd3Dt3j7/1mHbH4xAIBD4d3wAkO5R4dMxh0YAAAAASUVORK5CYII=","orcid":"","institution":"University of Calgary","correspondingAuthor":true,"prefix":"","firstName":"Ryan","middleName":"M","lastName":"Peters","suffix":""}],"badges":[],"createdAt":"2025-04-01 05:53:45","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-6349795/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-6349795/v1","draftVersion":[],"editorialEvents":[{"content":"https://doi.org/10.1186/s12984-025-01749-y","type":"published","date":"2025-10-31T15:58:06+00:00"}],"editorialNote":"","failedWorkflow":false,"files":[{"id":83623472,"identity":"8d5e2f8b-03f4-48df-8b49-a9ab60b8219c","added_by":"auto","created_at":"2025-05-29 15:54:40","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":3658931,"visible":true,"origin":"","legend":"\u003cp\u003eExperimental setup and data collection. (A) Participant sitting during electrical vestibular stimulation (EVS) while completing a questionnaire, with a 4-electrode bipolar configuration visible on the neck. (B) A participant performing a standing balance test on a soft surface, while the investigator measures standing balance using an accelerometer located behind the right mastoid process, connected to an app. (C) One minute sample of electrical vestibular stimulation waveform (±0.35mA, 1-300Hz) with power-spectral density of signal the 20 min signal inset above.\u003c/p\u003e","description":"","filename":"Figure1.png","url":"https://assets-eu.researchsquare.com/files/rs-6349795/v1/ceb54a6089a84473f17c9875.png"},{"id":83623470,"identity":"70b5f04f-4b35-49b2-9bb9-b27b1000813d","added_by":"auto","created_at":"2025-05-29 15:54:40","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":5543463,"visible":true,"origin":"","legend":"\u003cp\u003eExample data of postural sway for the floor eyes closed condition on Day 1 and Day 18 for a Stimulation and Sham participant. Head mounted IMU captured postural sway data over one minute sampled at 100 Hz. (\u003cstrong\u003eA\u003c/strong\u003e) Spatial scatter plot from a stimulation participant. The x-axis represents the medial-lateral acceleration (G), and y-axis represents the anterior-posterior acceleration (G) on Day 1 (left) and Day 18 (right). (\u003cstrong\u003eB\u003c/strong\u003e) Spatial scatter plots from a Sham participant. (\u003cstrong\u003eC\u003c/strong\u003e) Accelerometry timeseries for the stimulation participant, showing the acceleration in the x, y, and z directions on Day 1 (top) and Day 18 (bottom). (\u003cstrong\u003eD\u003c/strong\u003e) Accelerometry timeseries of a Sham participant.\u003c/p\u003e","description":"","filename":"Figure2.png","url":"https://assets-eu.researchsquare.com/files/rs-6349795/v1/529c756db585678aa580ae95.png"},{"id":83623464,"identity":"30162811-7483-4eb7-8673-f2c737908c9e","added_by":"auto","created_at":"2025-05-29 15:54:39","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":1189842,"visible":true,"origin":"","legend":"\u003cp\u003eCONSORT flow diagram for participation recruitment, allocation, follow-up, and analysis. A total of 65 participants were assessed for eligibility, with 10 excluded due to not meeting the inclusion criteria and 7 excluded due to declining to participate. The remaining 48 participants were randomized into the Stimulation group (n=24) and Sham group (n=24). All participants received their allocated intervention. However, 7 participants were lost to follow-up in the Stimulation group and 11 participants were lost to follow-up in the Sham group. After applying exclusion (completing all testing conditions), 21 participants were analyzed in the Stimulation group and 19 participants in the Sham group.\u003c/p\u003e","description":"","filename":"Figure3.png","url":"https://assets-eu.researchsquare.com/files/rs-6349795/v1/0a3c24b6939ae64953e14cfd.png"},{"id":83624701,"identity":"465de7b6-f845-4c87-a0e0-3594e1a76bbe","added_by":"auto","created_at":"2025-05-29 16:10:40","extension":"png","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":2441127,"visible":true,"origin":"","legend":"\u003cp\u003eGroup-level comparisons of normalized phybrata power across the EVS intervention and follow-up periods under four conditions: \u003cstrong\u003e(A)\u003c/strong\u003e Floor Eyes Open (EO), \u003cstrong\u003e(B)\u003c/strong\u003e Floor Eyes Closed (EC), \u003cstrong\u003e(C)\u003c/strong\u003e Foam Eyes Open (EO), and \u003cstrong\u003e(D)\u003c/strong\u003e Foam Eyes Closed (EC). Balance performance is separated by group, with the Sham group as blue and the Stimulation group as red. The x-axis denotes the days of the intervention (Day 1–18), followed by mean data points for 3-Month and 6-Month follow-up. Error bars represent ± 1 standard error. A dashed line at y=1 indicates normalized performance relative to Day 1, where data represent phybrata power ratios (e.g., Day 2 phybrata power = Day 2/Day 1). Note that the y-axis scale differs between panels to appropriately display the data.\u003c/p\u003e","description":"","filename":"Figure4.png","url":"https://assets-eu.researchsquare.com/files/rs-6349795/v1/e6fa840c0dc857246c16feb4.png"},{"id":83623910,"identity":"5675b979-5e6a-46af-b186-f80028ec8944","added_by":"auto","created_at":"2025-05-29 16:02:40","extension":"png","order_by":5,"title":"Figure 5","display":"","copyAsset":false,"role":"figure","size":1519559,"visible":true,"origin":"","legend":"\u003cp\u003eCorrelation between Week 1 performance and change in phybrata power over the intervention period (Week 6 – Week 1) for three conditions: (\u003cstrong\u003eA\u003c/strong\u003e) Floor Eyes Closed (EC), (\u003cstrong\u003eB\u003c/strong\u003e) Foam Eyes Open (EO), and (\u003cstrong\u003eC\u003c/strong\u003e) Foam Eyes Closed (EC). The Floor Eyes Open condition was excluded due to a lack of significant changes in LMM. Negative values in the change in phybrata power indicate improvements in balance performance throughout the intervention. Blue represents the Sham group, and red represents the Stimulation group, with lines of best fit shown for each group.\u003c/p\u003e","description":"","filename":"Figure5.png","url":"https://assets-eu.researchsquare.com/files/rs-6349795/v1/97e2af6ae4a805ab445f446d.png"},{"id":95039990,"identity":"01453c55-5128-4c81-9995-552c8fe16154","added_by":"auto","created_at":"2025-11-03 16:07:04","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":14692648,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-6349795/v1/d0ec2082-7fdc-4ca5-a0aa-a019a274c519.pdf"},{"id":83623462,"identity":"3bbd344a-0692-49a9-8aa4-f7b0d2501775","added_by":"auto","created_at":"2025-05-29 15:54:39","extension":"xls","order_by":0,"title":"","display":"","copyAsset":false,"role":"supplement","size":29184,"visible":true,"origin":"","legend":"","description":"","filename":"AdditionalFile1.xls","url":"https://assets-eu.researchsquare.com/files/rs-6349795/v1/5fdf8d20272ba536ab6662b4.xls"}],"financialInterests":"No competing interests reported.","formattedTitle":"Electrical vestibular stimulation to improve static balance in older adults: a randomized control trial","fulltext":[{"header":"Introduction","content":"\u003cp\u003eEvery year, 20\u0026ndash;30% of older Canadians report experiencing a fall, making falls the leading cause of injury-related hospitalizations in this demographic [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e]. This incidence rises to 32\u0026ndash;42% among those aged 70 and older [\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e]. Prior research has identified dizziness and imbalance as prevalent in up to 30% of older adults, with the risk of falls increasing significantly after the age of 60 [\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e], [\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e]. Falls cost the Canadian healthcare system ~\u003cspan\u003e$\u003c/span\u003e10.3\u0026nbsp;billion per year [\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e]. Injury due to falls can negatively impact the quality of life for older people and can lead to social isolation, loss of autonomy, bone fractures, reduction in mobility, and increased risk of osteoarthritis. As the global population aged 60 and over is projected to increase from 12\u0026ndash;22% by 2050, the search for effective treatments for balance deficits associated with aging becomes increasingly urgent [\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eHuman static and dynamic balance depends on central nervous system (CNS) integration and processing of somatosensory, visual, and vestibular sensory inputs to generate motor control outputs [\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e], [\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e]. Dysfunction in any of these systems can lead to dizziness or imbalance that can result in a higher risk of falls in aging populations [\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e]. Within the vestibular system, there are the otolith organs and semicircular canals which detect movement, providing linear and rotational acceleration information, respectively, to the vestibular nuclei via the vestibulocochlear nerve. Cortical projections to the cortex, then process these inputs, providing essential information about head orientation and stabilizing posture and gaze [\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e]. These pathways within the vestibular system collectively manage static and dynamic balance, gait, and posture in humans [\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e], [\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eVestibular dysfunction is common among older populations [\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e], [\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e]. Age-related degeneration affects nearly every type of vestibular-related cell and neural connection, including sensory end-organ hair cells, afferent nerve fibers, scarpa ganglion cells, vestibular nucleus neurons, and Purkinje cells within the cerebellum [\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e], [\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e]. This general loss of input and central integration of vestibular signals results in increased balance deficits with aging. Multiple pathophysiological mechanisms have been proposed to explain vestibular dysfunction in aging. The most common cause of balance dysfunction is the loss of mechanosensory hair cells [\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e]. However, given the poor correlation between clinical and histological findings, it is suggested that the vestibular system has compensatory mechanisms that can mask the effects of degeneration [\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e]. One example of a compensatory mechanism is central gain enhancement, where vestibular processing is amplified within the central nervous system (CNS) [\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e], [\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e], [\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e]. Other hypotheses suggest neuroplasticity in the central vestibular pathways [\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e]. Balance and gait stability begin to deteriorate once peripheral and central vestibular deficits surpass the compensatory capacity of the system [\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e], [\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e]. Currently, vestibular rehabilitation therapy (VRT) is indicated for nearly all vestibular injuries, excluding unstable lesions and ongoing labyrinthine pathology [\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e]. The mechanisms behind VRT include vestibular adaptation, which relies on readjusting the gain of vestibular reflexes, and vestibular substitution, which uses alternative sensory strategies (visual and proprioceptive) to replace vestibular function [\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eA growing body of research suggests that noisy Electrical Vestibular Stimulation (nEVS) is a promising approach to improving age-related declines in vestibular function [\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e], [\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e], [\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e], [\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e], [\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e]. EVS aims to enhance vestibular function by delivering imperceptible electrical currents to vestibular end organs and afferent neurons via electrodes placed over the left and right mastoids [\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e]. One hypothesized benefit of nEVS is that low levels of noise applied to the vestibular system can enhance the detection of sub-threshold signals [\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e]. This mechanism is believed to involve stochastic resonance, where the addition of noise enhances the detection of a signal that would otherwise be undetectable [\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e]. EVS stimulates hair cells and the vestibulocochlear nerve (CN VIII) evoking vestibular reflexes [\u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e], [\u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e23\u003c/span\u003e]. EVS has the potential to be a feasible, safe, and non-invasive treatment for balance deficits. Studies have identified the clinical applications of nEVS in treating conditions such as Meniere's disease, vestibular neuritis, bilateral vestibular disorders, vestibular schwannoma, Parkinson's disease, central ischemic lesions, motor myelopathies, anxiety, cognitive disorders, memory disorders, and age-related imbalance [\u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eFew studies have examined the effects of nEVS on older populations and there are currently no studies investigating the cumulative impact of repetitive nEVS. During stimulation, older adults had reductions in center of pressure and sway length [\u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e25\u003c/span\u003e], [\u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e26\u003c/span\u003e]. Testing across a wide frequency range (0.1\u0026ndash;640 Hz) at amplitudes of 0.4 and 1.0 mA in healthy young adults indicated that higher-frequency stimulation (up to 640 Hz) was most effective in reducing sway path length and velocity [\u003cspan citationid=\"CR27\" class=\"CitationRef\"\u003e27\u003c/span\u003e]. nEVS has the potential to improve postural instability, with these gains persisting for multiple hours post-stimulation [\u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e25\u003c/span\u003e]. Repeated nEVS sessions may induce further and sustained improvements in postural stability in healthy adults and e populations [\u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e25\u003c/span\u003e]. Further research is required to determine the underlying mechanism(s) responsible for the effects observed in previous EVS studies [\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e]. EVS-induced changes in balance could result from improved vestibular information processing in vestibular afferents or the activation of cortical regions, but the precise mechanism remains unknown [\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e]. There is also no consensus on optimal EVS delivery protocols [\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eThis study aims to advance and build upon existing research by developing a fixed regimen of nEVS dosing designed to maintain and restore vestibular system function and central processing to improve balance performance. The nEVS regimen involved low-amplitude wideband stimulation at \u0026plusmn;\u0026thinsp;0.35 mA from 0 to 300 Hz for 20 minutes, three times a week, over six weeks. We hypothesized that EVS application would induce sustained improvements in static balance and that these cumulative effects would persist up to six months post-stimulation.\u003c/p\u003e"},{"header":"Methods","content":"\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e\n \u003ch2\u003eParticipants\u003c/h2\u003e\n \u003cp\u003eInclusion criteria required participants to be older adults, between 50 and 100 years old. Exclusion criteria included individuals with a hearing aid, pacemaker, neurological disorder, or musculoskeletal disorder. Data was gathered from retirement and assisted living communities (n\u0026thinsp;=\u0026thinsp;20) and in-lab (n\u0026thinsp;=\u0026thinsp;20) using the same protocol. All procedures were approved by the University of Calgary Conjoint Health Research Ethics Board (Ethics ID: REB22-1006) and retrospectively registered as a clinical trial on February 25, 2025 (NCT06846047). All participants provided written informed consent before participation. Data collection ceased after recruiting 48 participants, with final analyses completed on participants that completed all testing sessions (n\u0026thinsp;=\u0026thinsp;40).\u003c/p\u003e\n\u003c/div\u003e\n\u003ch3\u003eExperimental Design\u003c/h3\u003e\n\u003cp\u003eThe study used a single-blind parallel randomized control trial design. Computer-generated simple randomization was used to assign participants into two groups, with an equal allocation of 24 participants to the Stimulation and Sham conditions. Group assignments were linked to participant numbers upon enrollment. There was no allocation concealment mechanism beyond participant blinding. The lead researcher was responsible for enrolling participants and sequentially assigning subject numbers in the order of enrollment. Participants were blinded to their group allocation. Additionally, two independent raters, who were not informed of group assignments, reviewed and removed artifacts from the data without participant identifiers. On the final day, participants were asked to identify which group they believed they were in to assess potential bias. During the first visit, participants completed baseline questionnaires (see Questionnaire section for more detail). Participants attended three sessions per week for six weeks, with follow-ups at 3 months and 6 months post-treatment. Each session lasted approximately 45 minutes. All procedures, including participation allocation, intervention administration, and outcome assessments, follow the pre-specified protocol. No study protocols or outcomes changed after the trial commenced.\u003c/p\u003e\n\u003cp\u003eFour balance assessments were administered via a smartphone app before and after stimulation. After the initial balance assessment, electrodes (3.8cm x 4.2cm) were placed bilaterally over the mastoid process and 2 cm from the midline at the C4 level on all participants. (Fig.\u0026nbsp;1). The Stimulation group received EVS, while the Sham group did not. Participants were seated and not required to complete any tasks during the 20 minutes of EVS dosing. Immediately after EVS, participants repeated the balance assessments. Follow-up sessions required participants to repeat the balance assessments twice, without the 20 minutes of EVS dosing.\u003c/p\u003e\n\u003cp\u003eParticipants removed footwear to complete the testing, which included a modified versions of the Romberg Test (a.k.a. modified Clinical Test of Sensory Interaction on Balance; mCTSIB), in which a head-mounted sensor was used to measure the participant\u0026rsquo;s ability to stand unassisted under four test conditions designed to specifically challenge the vestibular system, vision, and proprioception separately [\u003cspan class=\"CitationRef\"\u003e28\u003c/span\u003e], [\u003cspan class=\"CitationRef\"\u003e29\u003c/span\u003e]. The four balance assessments, each 60 seconds in duration, were carried out in the following sequence: eyes open on a firm surface (Floor EO), eyes closed on a firm surface (Floor EC), eyes open on a soft surface (Foam EO), and eyes closed on a soft surface (Foam EC). The soft surface was a foam pad produced by Node Fitness (16 x 12 x 2.5 inches) used to reduce somatosensory feedback from the feet [\u003cspan class=\"CitationRef\"\u003e4\u003c/span\u003e]. For all tasks, participants were instructed to stand still with their chin parallel to the floor, feet together, and arms by their sides. Investigators stood close to the participant during balance tasks for safety.\u003c/p\u003e\n\u003ch3\u003eElectrical Vestibular Stimulation\u003c/h3\u003e\n\u003cp\u003eThe skin was cleaned with an alcohol swab before attaching the EVS electrodes. EVS involved electrically activating the vestibular system by passing small electrical currents through electrodes placed on both mastoid processes and on both sides of the neck beside the spine at the level of the C4 vertebrae using a custom rechargeable battery-powered, dual constant current isolated stimulator module developed by Neursantys Inc. Participants in the Stimulation group received 20 minutes of EVS dosing at \u0026plusmn;\u0026thinsp;0.35 mA from 0 to 300 Hz. (Fig.\u0026nbsp;1C). Previous research has indicates that individuals typically begin to perceive vestibular sensations around 0.9-1.0 mA, with cutaneous sensations such as tingling or prickling occurring at similar or slightly lower intensities (0.85 mA) [\u003cspan class=\"CitationRef\"\u003e30\u003c/span\u003e]. Our study design used\u0026thinsp;\u0026plusmn;\u0026thinsp;0.35 mA to maximize participant comfort and justify the single-blinded study design. A frequency of 300 Hz was chosen as higher frequencies have be shown to reduce postural sway compared to lower frequencies [\u003cspan class=\"CitationRef\"\u003e31\u003c/span\u003e]. Both the Stimulation and Sham groups underwent identical procedures, including electrode placement, session duration, and balance assessment. The only difference was the stimulator was turned off for the Sham group.\u003c/p\u003e\n\u003ch3\u003eAccelerometry\u003c/h3\u003e\n\u003cp\u003eParticipants were instrumented with wearable accelerometers (Phybrata Sensor; PROTXX Inc.) placed vertically on their head above the right mastoid process. (Fig.\u0026nbsp;1B) [\u003cspan class=\"CitationRef\"\u003e32\u003c/span\u003e]. A previous study by Abdollah et al. (2021) validated the PROTXX sensor placed on the head as a measure of gait and balance performance. The accelerometers detect motion of the head in tri-axial directions (x, y, and z) [\u003cspan class=\"CitationRef\"\u003e33\u003c/span\u003e]. Accelerometers were attached to the skin with disposable double-sided medical adhesive tape after cleaning the skin with an alcohol swab. The accelerometers collected data sampled at 100 Hz and automatically relayed the kinematic data to a smartphone app-enabled, cloud data system. Accelerometers were removed after the balance assessments. Figure 2 shows sample EO and EC raw accelerometer times series data and spatial scatter plots collected before and after the EVS treatment. Balance assessments were performed using the smartphone app developed by PROTXX Inc. The app guided the investigator and participant through the experimental procedures using on-screen instructions and auditory cues. All tests described in the Experimental Design section were completed using this app.\u003c/p\u003e\n\u003ch3\u003eQuestionnaires\u003c/h3\u003e\n\u003cp\u003eFive questionnaires were administered during the first visit: the Activity Balance Confidence Scale (ABC), the Symbol Digit Modality Test (SDMT), Headache Questions for Baseline, the Migraine Disability Assessment Scale (MIDAS), and the Physical Activity Scale for the Elderly (PASE). Participants were asked each day if they had experienced any headaches since their previous visit and to rate their severity, with the results averaged over a month and compared between groups. Participants completed the ABC and MIDAS on the last day of the 6-week intervention. The ABC questionnaire measures an individual\u0026rsquo;s confidence in performing activities without losing balance. The ABC scale has been validated for older adults and is well-suited for identifying community-dwelling seniors who are beginning to lose confidence in their balance and who could benefit from a fall prevention intervention [\u003cspan class=\"CitationRef\"\u003e34\u003c/span\u003e]. The SDMT is a general measure of attention, processing speed, visual scanning, and motor speed by matching numbers to symbols as quickly as possible for 90 seconds [\u003cspan class=\"CitationRef\"\u003e35\u003c/span\u003e]. The validity and reliability of this test has been assessed for many different populations including older adults [\u003cspan class=\"CitationRef\"\u003e35\u003c/span\u003e]. The PASE is designed to assess activities commonly engaged by older adults and is a reliable and validated measure of physical activity for older adults to be used in research [\u003cspan class=\"CitationRef\"\u003e36\u003c/span\u003e]. The MIDAS is a five-item questionnaire designed to measure headache-related disability and it demonstrates good test-retest reliability across population-based samples in the United States and United Kingdom [\u003cspan class=\"CitationRef\"\u003e37\u003c/span\u003e].\u003c/p\u003e\n\u003cdiv id=\"Sec8\" class=\"Section2\"\u003e\n \u003ch2\u003eData Preparation\u003c/h2\u003e\n \u003cp\u003eTo ensure the accuracy and reliability of the data, two independent raters blind to subject groups manually reviewed the raw acceleration data for all testing sessions. Using a custom MATLAB code, any artifacts, such as sudden movements (e.g. talking, coughing, sneezing, dozing off, shift in gaze) or disruptions unrelated to standing balance, were identified and clipped from the data. This process ensured that the data used in the analysis represented actual standing balance performance, free from external noise or artifacts. A total of 1.94% of entire dataset was clipped due to the occurrence of artifacts in the recordings. Outliers were identified and removed from the dataset to avoid their influence on the analysis. Using the Explore option in SPSS, outliers were flagged based on extreme values in the positive or negative direction for each day, condition, and group. SPSS identifies outliers by calculating values that fall beyond 1.5 times the interquartile range (IQR) from the first or third quartile. Additionally, cases were excluded if sensor errors occurred during data collection (39 out of 7467, 0.005%).\u003c/p\u003e\n\u003c/div\u003e\n\u003ch3\u003eStatistical Tests\u003c/h3\u003e\n\u003cp\u003eAll statistical tests were analyzed using IBM SPSS (v28.0.1.0, IBM Corp., 2021, Armonk, NY) with an alpha level of 0.05 for the statistical significance threshold of all testing. A formal a prori sample size calculation was not performed prior to data collection. Given there is no previous study of this sort to base a sample size calculation off, we instead determined our sample size based on feasibility constraints, including capacity and available resources. The dependent variables extracted were the participants\u0026apos; degree of postural instability measured using the magnitude of phybrata power (Phybrata Power=(X\u003csup\u003e2\u003c/sup\u003e\u0026thinsp;+\u0026thinsp;Y\u003csup\u003e2\u003c/sup\u003e\u0026thinsp;+\u0026thinsp;Z\u003csup\u003e2\u003c/sup\u003e)*1.3*0.01*9.81\u003csup\u003e2\u003c/sup\u003e) to calculate the movement of the head regardless of direction according to Grafton et al. (2019) [\u003cspan class=\"CitationRef\"\u003e38\u003c/span\u003e]. Data was normalized across the study to each individual\u0026apos;s initial day performance, which expresses relative change from baseline and accounts for large inter-subject differences in baseline balance performance. To determine the therapeutic efficacy of repeated EVS sessions, phybrata power was analyzed using a linear mixed model analysis with subjects as the random factor, and group (Stimulation or Sham), session (Day 1 to 18), and interaction of group and day as fixed factors. Pairwise comparisons were used to compare Day 1\u0026rsquo;s performance to the subsequent days. A linear mixed model is best suited for this data analysis because it can compare data across multiple time points and handle missing data. Regression analyses were conducted to examine the relationship between Day 1 performance and change in performance across all conditions, with the Stimulation and Sham group analyzed separately. The questionnaire data was analyzed using regressions to explore the relationship between change in performance in Floor EC compared to SDMT scores, and Day 1 Floor EC performance against PRE ABC scores. Age and PASE scores were also evaluated as a predictor of SDMT, PRE ABC, and Day 1 Floor EC scores. T-tests were used to assess changes and differences between groups. Paired t-tests compared PRE ABC and POST ABC for both groups. Independent t-tests were performed to compare headache frequency between both groups. The effectiveness of the single-blind study design was tested with crosstabulation using a chi-squared test to determine if the distribution of correct and incorrect guesses was different from random guessing for both groups.\u003c/p\u003e"},{"header":"Results","content":"\u003cp\u003eParticipants were recruited between October 2022 and November 2023 from retirement homes, assisted living facilities and community around the University of Calgary. Out of the 48 participants initially enrolled in the study, only those who completed all testing sessions were included in the final analysis. This criterion resulted in a total of 40 participants (14 males and 26 females) (19 Sham, 21 Stimulation) whose data were analyzed. Participants who were unable to complete the foam testing were excluded, which accounted for the removal of 8 participants (5 Sham, 3 Stimulation). This approach ensured consistency across participants for all conditions and testing days. See Fig. 3 for CONSORT flow diagram of how participants flowed through the study. The sample from 40 older adults had a mean age of 77.7\u0026thinsp;\u0026plusmn;\u0026thinsp;11.8 years, height: 167.8\u0026thinsp;\u0026plusmn;\u0026thinsp;10.8 cm, and weight: 70.7\u0026thinsp;\u0026plusmn;\u0026thinsp;14.0 kg. The study was completed as originally intended, with all planned assessments and follow-ups carried out as per the protocol. No adverse effects of the intervention were reported.\u003c/p\u003e\n\u003cdiv id=\"Sec11\" class=\"Section2\"\u003e\n \u003ch2\u003eRetention\u003c/h2\u003e\n \u003cp\u003eParticipant retention diminished after the 6-week intervention. Of the 40 participants 27 completed the 3-month follow-up and 30 completed the 6-month follow-up. If a participant was unable to attend a scheduled follow-up, they were still permitted to complete later follow-ups as their schedule allowed.\u003c/p\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec12\" class=\"Section2\"\u003e\n \u003ch2\u003eBlindness\u003c/h2\u003e\n \u003cp\u003eOf the 15 participants assigned to the Sham group and retained to the 6-month follow-up session, 53.3% (n\u0026thinsp;=\u0026thinsp;8) correctly identified their group, while 46.7% (n\u0026thinsp;=\u0026thinsp;7) incorrectly thought they were in the Stimulation group. Conversely, of the 18 participants in the Stimulation group, 72.2% (n\u0026thinsp;=\u0026thinsp;13) correctly identified their group, while 27.8% (n\u0026thinsp;=\u0026thinsp;5) thought they were in the Sham group. A chi-square test was performed to assess whether participants\u0026apos; perceptions of their group assignment were associated with their actual group assignment. The test was not statistically significant, \u0026chi;\u0026sup2;(1, N\u0026thinsp;=\u0026thinsp;33)\u0026thinsp;=\u0026thinsp;2.238, p\u0026thinsp;=\u0026thinsp;0.135, indicating no evidence of an association between group assignment and perceived group.\u003c/p\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec13\" class=\"Section2\"\u003e\n \u003ch2\u003eEVS Reduces Sway in Older Adults Compared to Controls\u003c/h2\u003e\n \u003cp\u003eSee Table\u0026nbsp;1 for mean +/- SD for each group in the linear mixed model (LMM). In the LMM analysis, significant main effects of group were observed in Floor EC (F(1,635)\u0026thinsp;=\u0026thinsp;19.427, p\u0026thinsp;\u0026lt;\u0026thinsp;.001), Foam EO (F(1,599)\u0026thinsp;=\u0026thinsp;23.701, p\u0026thinsp;\u0026lt;\u0026thinsp;.001), and Foam EC (F(1,610)\u0026thinsp;=\u0026thinsp;17.560, p\u0026thinsp;\u0026lt;\u0026thinsp;.001) conditions, indicating differences between the Stimulation and Sham groups across conditions. Significant main effect of day was observed in the Foam EO (F(17,599)\u0026thinsp;=\u0026thinsp;3.148, p\u0026thinsp;\u0026lt;\u0026thinsp;.001) and Foam EC (F(17,610)\u0026thinsp;=\u0026thinsp;3.947, p\u0026thinsp;\u0026lt;\u0026thinsp;.001) conditions suggesting changes in performance over time. No significant interaction effects (group * day) were observed for any condition, including Floor EO (F(17,616)\u0026thinsp;=\u0026thinsp;0.244, p\u0026thinsp;=\u0026thinsp;.999), Floor EC (F(17,635)\u0026thinsp;=\u0026thinsp;0.692, p\u0026thinsp;=\u0026thinsp;.813), Foam EO (F(17,599)\u0026thinsp;=\u0026thinsp;0.969, p\u0026thinsp;=\u0026thinsp;.492), Foam EC (F(17,610)\u0026thinsp;=\u0026thinsp;0.537, p\u0026thinsp;=\u0026thinsp;.935). These results indicate that the Stimulation group improved more than the Sham group, however, both groups demonstrated improvements across testing sessions. Figure\u0026nbsp;4 shows the times series for Floor EO, Floor EC, Foam EO, and Foam EC for the Stimulation and Sham groups.\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003eTable 1.\u0026nbsp;\u003c/strong\u003e\u003cem\u003eMean \u0026plusmn; (SD) phybrata power values for Stimulation and Sham groups across balance conditions (Floor EO, Floor EC, Foam EO, and Foam EC) measured on Days 1\u0026ndash;18, 3-month, and 6-month follow-ups.\u003c/em\u003e\u003c/p\u003e\n \u003cp\u003eTable\u0026nbsp;1 (Additional File 1)\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003eNote\u0026nbsp;\u003c/strong\u003eValues are reported as the mean\u0026thinsp;\u0026plusmn;\u0026thinsp;standard deviation (SD). N represents the total sample size for each condition, while n represents the number of data points included after outlier removal. \u0026quot;Floor EO\u0026quot; refers to phybrata power measured during the Floor Eyes Open condition, \u0026quot;Floor EC\u0026quot; refers to Floor Eyes Closed, \u0026quot;Foam EO\u0026quot; refers to Foam Eyes Open, and \u0026quot;Foam EC\u0026quot; refers to Foam Eyes Closed. Day 1 values are normalized to a value of 1.00, and subsequent values represent performance relative to Day 1. Negative deviations indicate improved performance relative to baseline. Significance set to 0.05.\u003c/p\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec14\" class=\"Section2\"\u003e\n \u003ch2\u003ePairwise Comparisons\u003c/h2\u003e\n \u003cp\u003eTable\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e2\u003c/span\u003e shows p-values of pairwise comparisons of subsequent days to Day 1 with an asterisk denoting significance. Pairwise comparisons for the Floor EO condition of all days compared to Day 1 show no significant differences for both the Stimulation and Sham groups (all p\u0026thinsp;\u0026gt;\u0026thinsp;0.05). In the Floor EC condition, the Sham group exhibited no significant differences in performance across all pairwise comparisons with Day 1 (all p\u0026thinsp;\u0026gt;\u0026thinsp;0.05), suggesting no meaningful change over time. Conversely, the Stimulation group demonstrated significant reductions in normalized phybrata power starting on Day 5 compared to Day 1 (Mean Diff. = -0.180, p\u0026thinsp;=\u0026thinsp;0.03), with progressively larger reduction observed through Day 18 (Mean Diff = -0.302, p\u0026thinsp;\u0026lt;\u0026thinsp;0.001). By the 6-month follow up, the reduction in normalized phybrata power diminished slightly (Mean Diff = -0.149, p\u0026thinsp;=\u0026thinsp;0.092). In the Foam EO condition, the Sham group exhibited minimal changes in performance relative to Day 1, with significant improvements in normalized phybrata power observed on Day 14 (Mean Diff = -0.229, p\u0026thinsp;=\u0026thinsp;0.036), and Day 16 (Mean Diff = -0.268, p\u0026thinsp;=\u0026thinsp;0.018). In contrast, the Stimulation group displayed earlier and more consistent improvements in normalized phybrata power, with significant reductions first observed on Day 12 (Mean Diff = -0.216, p\u0026thinsp;=\u0026thinsp;0.034). These significant improvements persisted through Day 18 (Mean Diff = -0.208, p\u0026thinsp;=\u0026thinsp;0.043). In the Foam EC condition, the Sham group exhibited significant improvements compared to Day 1 performance starting on Day 13 and persisting through Day 18 except for Day 16 (p\u0026thinsp;=\u0026thinsp;0.051). The Stimulation group demonstrated earlier and more sustained improvements in normalized phybrata power, with significant differences starting at Day 3 (Mean Diff = -0.219, p\u0026thinsp;=\u0026thinsp;0.006) and persisting through the 6-month follow-up (Mean Diff = -0.456, p\u0026thinsp;\u0026lt;\u0026thinsp;0.001).\u003c/p\u003e\n \u003cdiv class=\"gridtable\"\u003e\u0026nbsp;\u003ctable id=\"Tab1\" border=\"1\"\u003e\n \u003ccaption language=\"En\"\u003e\n \u003cdiv class=\"CaptionNumber\"\u003eTable 2\u003c/div\u003e\n \u003cdiv class=\"CaptionContent\"\u003e\n \u003cp\u003e\u003cem\u003eP-values for pairwise comparisons of phybrata power relative to Day 1 for Stimulation and Sham groups across balance conditions (Floor EO, Floor EC, Foam EO, and Foam EC) on Days 2\u0026ndash;18, 3-month, and 6-month follow-ups.\u003c/em\u003e\u003c/p\u003e\n \u003c/div\u003e\n \u003c/caption\u003e\n \u003ccolgroup cols=\"9\"\u003e\u003c/colgroup\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003cth align=\"left\" rowspan=\"2\"\u003e\n \u003cp\u003eDay (vs Day 1)\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003eFloor EO\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003eFloor EC\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003eFoam EO\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003eFoam EC\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eSham\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eStim\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eSham\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eStim\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eSham\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eStim\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eSham\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eStim\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.673\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.979\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.844\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.273\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.658\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.317\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.946\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.403\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.835\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.516\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.589\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.348\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.436\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.277\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.243\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.006*\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.302\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.646\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.445\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.240\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.464\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.131\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.694\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.005*\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.244\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.370\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.162\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.030*\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.784\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.193\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.115\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e\u0026lt;\u0026thinsp;0.001*\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.303\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.394\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.275\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.028*\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.651\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.071\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.205\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e\u0026lt;\u0026thinsp;0.001*\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e7\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.978\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.878\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.354\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.128\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.814\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.160\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.220\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.012*\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.889\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.411\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.245\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.012*\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.056\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.153\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.259\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e\u0026lt;\u0026thinsp;0.001*\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e9\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.291\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.869\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.287\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.011*\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.057\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.351\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.108\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e\u0026lt;\u0026thinsp;0.001*\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e10\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.123\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.952\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.210\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.039*\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.568\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.055\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.122\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e\u0026lt;\u0026thinsp;0.001*\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e11\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.297\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.615\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.206\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.086\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.086\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.078\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.496\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e\u0026lt;\u0026thinsp;0.001*\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e12\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.974\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.710\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.107\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.004*\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.133\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.034*\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.067\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.010*\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e13\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.281\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.425\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.677\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.002*\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.091\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.040*\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.017*\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e\u0026lt;\u0026thinsp;0.001*\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e14\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.661\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.673\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.675\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.002*\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.036*\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e\u0026lt;\u0026thinsp;0.001*\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.046*\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e\u0026lt;\u0026thinsp;0.001*\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e15\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.251\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.936\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.252\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.004*\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.072\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.048*\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.017*\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e\u0026lt;\u0026thinsp;0.001*\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e16\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.149\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.538\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.558\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.007*\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.018*\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.016*\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.051\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e\u0026lt;\u0026thinsp;0.001*\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e17\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.454\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.555\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.537\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e\u0026lt;\u0026thinsp;0.001*\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.176\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.01*\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.025*\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e\u0026lt;\u0026thinsp;0.001*\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e18\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.523\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.253\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.270\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e\u0026lt;\u0026thinsp;0.001*\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.471\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.043*\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.023*\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e\u0026lt;\u0026thinsp;0.001*\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3M\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.704\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.428\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.711\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.007*\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.146\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.230\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.062\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.001*\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e6M\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.678\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.608\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.759\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.092\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.240\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.051\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.923\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e\u0026lt;\u0026thinsp;0.001*\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003ctfoot\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"9\"\u003e\u003cem\u003eNote.\u003c/em\u003e Asterisks (*) denote significant differences relative to Day 1 with \u0026alpha;\u0026thinsp;=\u0026thinsp;0.05 level. P-values indicate the results of pairwise comparisons for each group (Stimulation and Sham) and condition. Days are listed chronologically (Day 2\u0026ndash;18, 3-month [3M], and 6-month [6M]) for consistency across conditions.\u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tfoot\u003e\n \u003c/table\u003e\n \u003c/div\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec15\" class=\"Section2\"\u003e\n \u003ch2\u003eRegression Analysis\u003c/h2\u003e\n \u003cp\u003eFor Floor EC, initial (baseline) performance significantly predicted change in performance for the Stimulation group (F (1, 19)\u0026thinsp;=\u0026thinsp;97.40, p\u0026thinsp;\u0026lt;\u0026thinsp;0.001, R\u0026sup2; = 0.837). Baseline scores negatively predicted improvement (B = -0.716, p\u0026thinsp;\u0026lt;\u0026thinsp;0.001), indicating that participants with poorer initial balance improved the most. The Sham group did not demonstrate a significant relationship (F (1, 17)\u0026thinsp;=\u0026thinsp;0.105, p\u0026thinsp;=\u0026thinsp;0.750, R\u0026sup2; = 0.006). In Foam EO, significant relationships were observed for both Stimulation groups (F(1, 18)\u0026thinsp;=\u0026thinsp;142.02, p\u0026thinsp;\u0026lt;\u0026thinsp;0.001, R\u0026sup2; = 0.888) and Sham (F(1, 16)\u0026thinsp;=\u0026thinsp;16.66, p\u0026thinsp;\u0026lt;\u0026thinsp;0.001, R\u0026sup2; = 0.510), with larger baseline balance impairments predicting larger balance improvements (B = -0.648, p\u0026thinsp;\u0026lt;\u0026thinsp;0.001 for Stimulation; B = -0.407, p\u0026thinsp;\u0026lt;\u0026thinsp;0.001 for Sham). In the Foam EC condition, baseline performance was a significant predictor of change in performance for only the Stimulation group (F(1,19)\u0026thinsp;=\u0026thinsp;22.87, p\u0026thinsp;\u0026lt;\u0026thinsp;0.001, R\u003csup\u003e2\u003c/sup\u003e\u0026thinsp;=\u0026thinsp;0.546) with larger Day 1 balance impairments again predicting greater balance improvements (B = -0.432, p\u0026thinsp;\u0026lt;\u0026thinsp;0.001), while the Sham group did not exhibit a significant relationship (F(1,15\u0026thinsp;=\u0026thinsp;1.03, p\u0026thinsp;=\u0026thinsp;0.326, R\u0026sup2; = 0.254, B = -0.147). Figure 4 shows scatterplots of the Floor EC, Foam EO, and Foam EC Day 1 performance vs change in performance.\u003c/p\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec16\" class=\"Section2\"\u003e\n \u003ch2\u003eQuestionnaire Analysis\u003c/h2\u003e\n \u003cp\u003eAn independent t-test comparing headache frequency between the Stimulation and Sham groups found no significant difference (p\u0026thinsp;=\u0026thinsp;0.473) throughout the 6-week intervention. There were no significant differences in MIDAS scores from pre- to post-intervention for the Stimulation group (p\u0026thinsp;=\u0026thinsp;0.302) and the Sham group (p\u0026thinsp;=\u0026thinsp;0.363). There was a significant increase in balance confidence scores from pre- to post-intervention in both the Stimulation (p\u0026thinsp;=\u0026thinsp;0.023) and Sham groups (p\u0026thinsp;=\u0026thinsp;0.019). In the Sham group, regression analysis revealed a significant relationship between Physical Activity Scale for the Elderly (PASE) scores and changes in phybrata power in the Floor EC condition (F(1,12)\u0026thinsp;=\u0026thinsp;7.019, p\u0026thinsp;=\u0026thinsp;0.021, R\u003csup\u003e2\u003c/sup\u003e\u0026thinsp;=\u0026thinsp;0.369). Higher physical activity levels were associated with smaller improvements in phybrata power (i.e., less reduction in phybrata power). PASE scores accounted for 36.9% of the variance in the change in phybrata power. While the Stimulation groups regression analysis revealed no significant relationship (R\u0026thinsp;=\u0026thinsp;0.208, F(1,17)\u0026thinsp;=\u0026thinsp;0.767, p\u0026thinsp;=\u0026thinsp;0.393, R\u003csup\u003e2\u003c/sup\u003e\u0026thinsp;=\u0026thinsp;0.043), with PASE scores explaining 4.3% of the variance. This was not significant for the Foam EO and Foam EC conditions for both groups. A significant negative correlation was observed between PRE ABC scores and baseline performance in the Floor EC condition (r = -0.652, p\u0026thinsp;\u0026lt;\u0026thinsp;0.001), indicating that participants with higher balance confidence exhibited lower phybrata power. A strong negative correlation was identified between age and SDMT scores (r = -0.799, p\u0026thinsp;\u0026lt;\u0026thinsp;0.001), demonstrating that older participants exhibited lower cognitive performance. Age was also negatively correlated with balance confidence (r = -0.545, p\u0026thinsp;\u0026lt;\u0026thinsp;0.001), suggesting that older participants reported lower confidence in performing balance-related tasks. There were no significant relationships between SDMT scores and balance performance.\u003c/p\u003e\n\u003c/div\u003e"},{"header":"Discussion","content":"\u003cp\u003eThis study demonstrates that cumulative EVS dosing is a novel and effective therapeutic approach for improving balance in older adults. Compared to the Sham group, which showed no significant improvement from baseline to the end of the intervention for all condition except Foam EC, the Stimulation group exhibited substantial and sustained reductions in phybrata power across challenging sensory conditions. These findings provide evidence that the observed improvements in the EVS group are likely not attributable to natural learning effects or practice but instead reflect the efficacy of the intervention. The lack of significant improvements in simpler tasks, such as the Floor EO condition, suggests that EVS is most effective under conditions requiring greater reliance on vestibular and proprioceptive inputs, where sensory integration plays a critical role. The results from the foam conditions highlight the cumulative impact of repeated EVS dosing. Significant reductions in phybrata power in the Stimulation group began as early as Day 12 in the Floor EC condition and Day 3 in the Foam EC condition, with these improvements persisting to the three month follow up (floor EC) and six month follow up (foam EC). In contrast, the Sham group displayed delayed and inconsistent improvements, emphasizing the role of EVS in driving these outcomes. Together, these findings establish EVS as a minimally invasive, portable, and promising intervention for addressing balance deficits in aging populations.\u003c/p\u003e \u003cdiv id=\"Sec18\" class=\"Section2\"\u003e \u003ch2\u003ePotential Peripheral Mechanisms\u003c/h2\u003e \u003cp\u003eThe improvements in balance observed in this study could be attributed to peripheral mechanisms of EVS. Vestibular afferents, which transmit signals from the vestibular sensory organs to the brain, are crucial for maintaining postural stability. Prior research supports the idea that EVS directly influences vestibular afferent activity, enhancing the processing of vestibular signals necessary for balance control. For instance, Goldberg et al. (1984) demonstrated that intra-vestibule EVS modulates vestibular afferent firing, specifically from the otolith organs and semicircular canals. This finding suggests that EVS enhances the input generation of peripheral vestibular signals to the vestibular nuclei, thereby improving postural stability during challenging balance tasks [\u003cspan citationid=\"CR39\" class=\"CitationRef\"\u003e39\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eThe findings from Kwan et al. (2019) further reinforce this notion by showing that transcranial EVS activates both semicircular canal and otolith afferents in nonhuman primates [\u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e]. This balanced activation of vestibular afferents may account for the improvements in sensory integration observed in participants performing tasks that rely heavily on vestibular and proprioceptive inputs, such as the Floor EC and Foam EC conditions. By increasing the sensitivity of vestibular afferents to subthreshold signals, EVS likely enhances the neural inputs that enable detection of subtle head movements to maintain postural stability. Additionally, it is proposed that EVS-induced improvements in postural stability may be driven by stochastic resonance, a phenomenon in which noise added to a system enhances signal detection [\u003cspan citationid=\"CR40\" class=\"CitationRef\"\u003e40\u003c/span\u003e], but this only occurs during stimulation, and cannot account for the persistent effects observed here with repeated EVS exposure. The cumulative effects of EVS dosing may amplify vestibular afferent inputs, leading to pronounced improvements in vestibular balance control. Participants in the Stimulation group showed significant reductions in phybrata power as early as Day 3 in the Foam EC condition, showing the rapid impact of EVS on peripheral vestibular processing.\u003c/p\u003e \u003cp\u003eAge-related changes in vestibular hair cell density and function may further explain the effectiveness of EVS in older adults. EVS not only stimulates vestibular afferents but may also influence vestibular hair cells [\u003cspan citationid=\"CR41\" class=\"CitationRef\"\u003e41\u003c/span\u003e]. Although the capacity for vestibular hair cell regeneration in humans is limited, immature hair bundles in the utricular epithelia of adults over 60 years old [\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e]. These findings imply that the vestibular epithelia retain some capacity for regeneration throughout life, via either direct trans-differentiation of supporting cells into hair cells or by supporting cell division and asymmetric differentiation, where one daughter cell trans-differentiates into a hair cell and the other remains as a supporting cell [\u003cspan citationid=\"CR42\" class=\"CitationRef\"\u003e42\u003c/span\u003e]. EVS may stimulate these immature hair bundles, potentially supporting functional recovery of vestibular sensory cells. Further research is required to validate whether EVS directly facilitates hair cell regeneration or if its effects are limited to afferent stimulation. The modulation of afferent firing by EVS may also address the age-related decline in vestibular sensitivity. Vestibular hair cell loss contributes to reduced sensory input in older adults, leading to balance impairments [\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e]. By enhancing vestibular afferent sensitivity and potentially stimulating remaining hair cells, EVS could compensate for this sensory loss, allowing older adults to maintain or improve postural stability under challenging conditions.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec19\" class=\"Section2\"\u003e \u003ch2\u003ePotential Central Mechanisms\u003c/h2\u003e \u003cp\u003eThe potential central mechanisms underlying the improvements in balance observed in this study may involve neuroplasticity within the vestibular nuclei and associated neural pathways. The vestibular nuclei are critical for processing sensory inputs from the vestibular system and integrating these signals with proprioceptive and visual information to maintain postural control. Neuroplasticity within these nuclei may play a key role in the sustained balance improvements observed in participants receiving EVS.\u003c/p\u003e \u003cp\u003eEvidence from previous studies supports the potential for long-term potentiation (LTP) within the vestibular nuclei, a neural mechanism that enhances synaptic efficacy [\u003cspan citationid=\"CR43\" class=\"CitationRef\"\u003e43\u003c/span\u003e]. This finding aligns with the hypothesis that repeated EVS sessions may promote LTP in the vestibular nuclei, thereby improving the processing of vestibular inputs. Similarly, the vestibular nuclei's capacity for neuroplasticity, particularly following vestibular system stimulation or injury [\u003cspan citationid=\"CR44\" class=\"CitationRef\"\u003e44\u003c/span\u003e], [\u003cspan citationid=\"CR45\" class=\"CitationRef\"\u003e45\u003c/span\u003e]. These studies suggest that repeated EVS exposure may facilitate functional changes in the vestibular nuclei, enhancing their ability to process and respond to sensory inputs.\u003c/p\u003e \u003cp\u003eVestibular neuroplasticity, specifically synaptic plasticity within the vestibular nuclei, may account for the prolonged balance improvements observed following nEVS [\u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e25\u003c/span\u003e]. Significant post-stimulation effects lasting several hours have been observed in healthy older adults, supporting the idea that nEVS induces neuroplastic changes in the central vestibular pathways [\u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e25\u003c/span\u003e]. This aligns with our study's findings, where participants in the Stimulation group exhibited sustained improvements in phybrata power in the Foam EC condition, with effects persisting through the 6-month follow-up. The extended duration of these improvements suggests that cumulative nEVS may induce long-lasting neuroplastic changes in the central vestibular system.\u003c/p\u003e \u003cp\u003eAdditionally, the cerebellum, which is closely linked to the vestibular nuclei, likely contributes to the observed effects. The cerebellum plays a crucial role in fine-tuning motor control and balance by integrating sensory inputs and coordinating motor responses. Neuroplasticity within the cerebellum, particularly in its connections with the vestibular nuclei, may enhance the central processing of vestibular inputs. nEVS can activate cortical areas beyond the vestibular nuclei, including regions associated with motor planning and balance control [\u003cspan citationid=\"CR46\" class=\"CitationRef\"\u003e46\u003c/span\u003e]. While our study employed subthreshold nEVS levels that were unlikely to evoke direct cortical activation, the observed improvements suggest that repeated dosing may strengthen vestibular pathways.\u003c/p\u003e \u003cp\u003eAge-related reductions in vestibular nuclei neurons and cerebellar function may further highlight the importance of nEVS-induced neuroplasticity in older adults. Aging leads to neuronal loss in the vestibular nuclei, contributing to declines in balance performance [\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e], [\u003cspan citationid=\"CR47\" class=\"CitationRef\"\u003e47\u003c/span\u003e]. nEVS may counteract these effects by enhancing synaptic efficacy and promoting neuroplastic changes within central pathways, allowing older adults to maintain or improve postural stability.\u003c/p\u003e \u003cp\u003eIn addition to enhancing balance, nEVS may also have broader implications for central neural function. Higher EVS input levels activate cortical areas involved in visual and motor integration, suggesting that repeated dosing could improve sensory integration and motor planning [\u003cspan citationid=\"CR46\" class=\"CitationRef\"\u003e46\u003c/span\u003e]. While our study focused on subthreshold stimulation, future research should investigate whether higher EVS intensities could amplify these central effects.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec20\" class=\"Section2\"\u003e \u003ch2\u003eClinical Significance\u003c/h2\u003e \u003cp\u003eThis study demonstrates that nEVS is a promising therapeutic tool for improving balance in older adults, particularly in conditions that rely heavily on vestibular and proprioceptive inputs. Improvements observed in the Stimulation group, especially in the Foam EC and Foam EO conditions, emphasize its utility in targeting sensory integration processes critical for postural stability. Peripheral vestibular deficits are prevalent among older populations and exacerbate age-related declines in balance, further underlining the clinical need for interventions that enhance vestibular function [\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e]. High fall-risk individuals identified through the Sensory Organization Test commonly displayed vestibular deficits [\u003cspan citationid=\"CR48\" class=\"CitationRef\"\u003e48\u003c/span\u003e]. This suggests that interventions like EVS, which target vestibular system enhancement, may have the greatest impact on individuals with greater baseline impairments. Tailoring EVS treatment based on individual vestibular thresholds could further optimize its effectiveness. While nEVS has been shown to induce short-term balance enhancements, the retention of these effects was poor [\u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e25\u003c/span\u003e]. However, with cumulative dosing treatments, retention was observed up to six months post-stimulation, suggesting neuroplastic changes and the potential to transition individuals from high- to low-risk profiles over 18 sessions.\u003c/p\u003e \u003cp\u003eThe safety and tolerability of EVS as an intervention were further supported by the absence of significant differences in headache frequency or MIDAS scores between the Stimulation and Sham groups, indicating that the intervention does not induce notable headaches or migraines. Additionally, there were no other adverse effects to report with the stimulation used in this study. Both groups demonstrated significant improvements in balance confidence scores (PRE ABC vs. POST ABC), aligning with the reductions in phybrata power and suggesting that EVS not only enhances physical balance but also positively impacts participants' confidence in their ability to perform balance-related tasks. A significant negative correlation between PRE ABC scores and baseline phybrata power in the Floor EC condition indicates that individuals with higher balance confidence exhibited lower phybrata power (better performance) at baseline. Additionally, the relationship between PRE ABC scores and age highlights the importance of addressing age-related declines in both physical and psychological aspects of balance. Similarly, the strong negative correlation between SDMT scores and age highlight age-related cognitive decline, yet the lack of a relationship between SDMT scores and changes in phybrata power during the intervention suggests that EVS-induced balance improvements were independent of participants' cognitive performance. This finding highlights EVS as a targeted intervention for physical balance deficits rather than cognitive impairments. However, future studies should look at the relationship with EVS to help with learning and spatial awareness.\u003c/p\u003e \u003cp\u003eThe PASE results further emphasize the robustness of the EVS intervention. While higher PASE scores (indicative of greater baseline physical activity) were associated with smaller improvements in phybrata power in the Sham group, no significant relationship was observed in the Stimulation group in the Floor EC condition. This suggests that EVS provides balance improvements regardless of participants' baseline physical activity levels. In contrast, the Sham group\u0026rsquo;s dependency on PASE scores highlights the role of natural learning effects or activity-related benefits in driving improvements. The independence of the Stimulation group from PASE-related effects demonstrates that nEVS works consistently, making it an accessible and scalable therapeutic option for a broader range of older adults, irrespective of their activity levels.\u003c/p\u003e \u003cp\u003eSince EVS stimulates a cranial nerve, it has been explored for potential improvements in anxiety, memory, and cognition [\u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e]. Participants undergoing EVS dosing can easily incorporate additional therapies tailored to their needs or combine them with balance exercises to further enhance balance improvements. This versatility enhances EVS both as a standalone treatment and as a complementary component of a holistic therapeutic strategy aimed at improving balance and reducing fall risk in vulnerable populations. EVS has proven to be an effective treatment for improving standing balance in older adults. It is easy to use, portable, low-cost, and minimally invasive, making it a valuable tool to counteract age-related decline. Participants in this study reported no adverse side effects, aligning with findings from subthreshold EVS studies [\u003cspan citationid=\"CR49\" class=\"CitationRef\"\u003e49\u003c/span\u003e]. However, it is noteworthy that suprathreshold EVS (\u0026gt;\u0026thinsp;1 mA) may induce more pronounced side effects, such as vertigo and metallic taste [\u003cspan citationid=\"CR50\" class=\"CitationRef\"\u003e50\u003c/span\u003e]. The portability of EVS, combined with a head-mounted accelerometer, facilitates seamless balance assessments and treatments, enabling integration into various settings, including retirement homes, for real-world data collection.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec21\" class=\"Section2\"\u003e \u003ch2\u003eLimitations\u003c/h2\u003e \u003cp\u003eThis study has several limitations. First, no a priori sample size calculation was performed, making it unclear whether the initial proof of concept study would be adequately powered to detect effects. However, this paper will serve for proper sample size calculations to ensure future studies can adequately power their experiments. Second, the single-blind design was chosen due to the subthreshold intensity of the stimulus. However, to assess the effectiveness of blinding, participants were asked to guess what their group assignment was, and the distribution of guesses was not significantly different from random guessing suggesting successful blinding. The manual data cleaning process included removing artifacts of talking, head shaking, sneezing, or other anomalous movements which removed 1.94% of the total data. In future studies, a machine learning algorithm could be developed to clean the dataset, reducing potential biases from human error. Additionally, while the study demonstrated significant balance improvements in challenging sensory conditions (e.g., Foam EC), the generalizability of these findings to broader populations remains uncertain. The participants were older adults, and the effects of EVS in individuals with more severe balance deficits, vestibular dysfunction, or neurological conditions need further exploration. However, given participants with the poorest balance initial performance showed the largest improvement, we suggest that EVS will be effective in clinical populations with more severe balance deficits. Lastly, while the current study focused on static balance, assessing dynamic balance and gait stability would provide a more comprehensive understanding of EVS\u0026rsquo;s impact on mobility, quality of life, and fall prevention.\u003c/p\u003e \u003c/div\u003e"},{"header":"Conclusion","content":"\u003cp\u003eThis study provides evidence that cumulative EVS is a novel, effective intervention for improving balance in older adults. Through a comprehensive evaluation of balance performance across multiple sensory conditions, we demonstrated significant and sustained improvements in postural control, particularly in challenging conditions that increase reliance on vestibular inputs, such as Floor EC, Foam EO, and Foam EC. The results emphasize the capacity of EVS to enhance sensory reweighting and facilitate neuroplastic changes, leading to improved balance stability and confidence. By showing that participants with poorer baseline performance achieved greater improvements, this study highlights the potential of EVS to target high-risk individuals, reducing fall risk and addressing age-related vestibular decline. These findings also support the hypothesis that EVS enhances both peripheral and central vestibular processing, which may underlie the observed improvements in postural control. Additionally, the portability and scalability of EVS make it an attractive option for community and clinical use, from retirement homes to outpatient rehabilitation clinics.\u003c/p\u003e"},{"header":"Abbreviations","content":"\u003cp\u003eABC – Activities-specific Balance Confidence Scale\u003c/p\u003e\n\u003cp\u003eCNS – Central Nervous System\u003c/p\u003e\n\u003cp\u003eEO – Eyes Open\u003c/p\u003e\n\u003cp\u003eEC – Eyes Closed\u003c/p\u003e\n\u003cp\u003eEVS – Electrical Vestibular Stimulation\u003c/p\u003e\n\u003cp\u003eIMU – Inertial Measurement Unit\u003c/p\u003e\n\u003cp\u003eIQR – Interquartile Range\u003c/p\u003e\n\u003cp\u003eLMM -Linear Mixed Model\u003c/p\u003e\n\u003cp\u003emCTSIB – Modified Clinical Test of Sensory Interaction on Balance\u003c/p\u003e\n\u003cp\u003eMIDAS – Migraine Disability Assessment Scale\u003c/p\u003e\n\u003cp\u003enEVS – Noisy Electrical Vestibular Stimulation\u003c/p\u003e\n\u003cp\u003ePASE – Physical Activity Scale for the Elderly\u003c/p\u003e\n\u003cp\u003eSDMT – Symbol Digit Modalities Test\u003c/p\u003e\n\u003cp\u003eVRT – Vestibular Rehabilitation Therapy\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eEthics approval and consent to participate.\u0026nbsp;\u003c/strong\u003eAll procedures were approved by the University of Calgary Conjoint Health Research Ethics Board (Ethics ID: REB22-1006) and retrospectively registered as a clinical trial on February 25, 2025 (NCT06846047). All participants provided written informed consent before participation.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConsent for publication.\u0026nbsp;\u003c/strong\u003eThe authors give consent for publication.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAvailability of data and materials\u003c/strong\u003e. The dataset supporting the findings of this study is publicly available via Borealis:\u003c/p\u003e\n\u003cp\u003eKing, Jordan, 2025, Replication Data for: Electrical vestibular stimulation to improve static balance in older adults: a randomized control trial, https://doi.org/10.5683/SP3/SWWBUR, Borealis, DRAFT VERSION.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCompeting interests.\u0026nbsp;\u003c/strong\u003eThe authors have no competing interests.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding.\u003c/strong\u003e This research was funded by Natural Sciences and Engineering Research Council Discovery (RGPIN-2020-06068) and Idea-to-Innovation grants (I2IPJ 548811-2020), as well as a New Frontiers in Research Fund grant (NFRFR-2021-00199) awarded to RMP\u003cstrong\u003e. \u0026nbsp;\u003c/strong\u003eJAK was funded by the Hotchkiss Brain Institute (HBI) Harley N. Hotchkiss Graduate Scholarship in Neuroscience. Neursantys contributed funding for research assistants, participation awards, and parking expenses.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthors' contributions.\u0026nbsp;\u003c/strong\u003eJAK, JDR, and RMP was involved in all stages of the project including study design, data collection, analysis, interpretation, and manuscript writing. NW, NR, JAB, NM, AC, SC, EF, and RMP assisted with data collection. Data analysis was conducted by JAK, NR, AC, and MS. Manuscript preparation was done by JAK and NW. The final manuscript was reviewed and edited by SLO, JDR, JR, and RMP. All authors read and approved the final manuscript.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAcknowledgements.\u0026nbsp;\u003c/strong\u003eThe authors would like to acknowledge United Active Living Fish Creek, United Active Living Garrison Green, and Verve The Lodge for permitting data collection at their retirement and assisted living communities. Special thanks to all participants for their dedication throughout the 7.5-month protocol, and to the undergraduate research assistants who contributed significantly to data collection.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003ePublic Health Agency of Canada. Seniors\u0026rsquo; falls in Canada. Second report, Public Health Agency of Canada, Ottawa, ON, 2014. Accessed: Aug. 09, 2024. [Online]. Available: \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://www.canada.ca/en/public-health/services/publications/healthy-living/seniors-falls-canada-second-report.html\u003c/span\u003e\u003cspan address=\"https://www.canada.ca/en/public-health/services/publications/healthy-living/seniors-falls-canada-second-report.html\" targettype=\"URL\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003ePublic Health Agency of Canada. Surveillance Report on Falls Among Older Adults in Canada, Public Health Agency of Canada, Ottawa, Ontario, Canada, HP35-154/2022E-PDF, Mar. 2022.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eIwasaki S, Yamasoba T. Dizziness and Imbalance in the Elderly: Age-related Decline in the Vestibular System. Aging Dis. 2015;6(1):38. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.14336/AD.2014.0128\u003c/span\u003e\u003cspan address=\"10.14336/AD.2014.0128\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eBaloh RW, et al. Comparison of Static and Dynamic Posturography in Young and Older Normal People. J Am Geriatr Soc. Apr. 1994;42(4):405\u0026ndash;12. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1111/j.1532-5415.1994.tb07489.x\u003c/span\u003e\u003cspan address=\"10.1111/j.1532-5415.1994.tb07489.x\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eParachute. Cost of Injury in Canada 2021, Oct. 2024. Accessed: Jan. 15, 2025. [Online]. Available: \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://parachute.ca/en/professional-resource/cost-of-injury-in-canada/\u003c/span\u003e\u003cspan address=\"https://parachute.ca/en/professional-resource/cost-of-injury-in-canada/\" targettype=\"URL\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eWorld Health Organization. Ageing and health. Oct. 2024.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eBrosel S, Strupp M. The Vestibular System and Ageing, in \u003cem\u003eBiochemistry and Cell Biology of Ageing: Part II Clinical Science\u003c/em\u003e, vol. 91, J. R. Harris and V. I. Korolchuk, Eds., in Subcellular Biochemistry, vol. 91., Singapore: Springer Singapore, 2019, pp. 195\u0026ndash;225. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1007/978-981-13-3681-2_8\u003c/span\u003e\u003cspan address=\"10.1007/978-981-13-3681-2_8\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eBaloh RW, Spain S, Socotch TM, Jacobson KM, Bell T. Posturography and Balance Problems in Older People. J Am Geriatr Soc. Jun. 1995;43:638\u0026ndash;44. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1111/j.1532-5415.1995.tb07198.x\u003c/span\u003e\u003cspan address=\"10.1111/j.1532-5415.1995.tb07198.x\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eRossignol S, Dubuc R, Gossard J-P. Dynamic Sensorimotor Interactions in Locomotion, \u003cem\u003ePhysiol. Rev.\u003c/em\u003e, vol. 86, no. 1, pp. 89\u0026ndash;154, Jan. 2006, \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1152/physrev.00028.2005\u003c/span\u003e\u003cspan address=\"10.1152/physrev.00028.2005\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eZalewski C. Aging of the Human Vestibular System. Semin Hear. Jul. 2015;36(03):175\u0026ndash;96. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1055/s-0035-1555120\u003c/span\u003e\u003cspan address=\"10.1055/s-0035-1555120\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eTaylor RR et al. Jun., Characterizing human vestibular sensory epithelia for experimental studies: new hair bundles on old tissue and implications for therapeutic interventions in ageing, \u003cem\u003eNeurobiol. Aging\u003c/em\u003e, vol. 36, no. 6, pp. 2068\u0026ndash;2084, 2015, \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1016/j.neurobiolaging.2015.02.013\u003c/span\u003e\u003cspan address=\"10.1016/j.neurobiolaging.2015.02.013\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eJahn K. Inverse U-shaped curve for age dependency of torsional eye movement responses to galvanic vestibular stimulation. Brain. Apr. 2003;126(7):1579\u0026ndash;89. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1093/brain/awg163\u003c/span\u003e\u003cspan address=\"10.1093/brain/awg163\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eDalton BH, Blouin J-S, Allen MD, Rice CL, Inglis JT. The altered vestibular-evoked myogenic and whole-body postural responses in old men during standing. Exp Gerontol. Dec. 2014;60:120\u0026ndash;8. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1016/j.exger.2014.09.020\u003c/span\u003e\u003cspan address=\"10.1016/j.exger.2014.09.020\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003ePeters RM, Blouin J-S, Dalton BH, Inglis JT. Older adults demonstrate superior vestibular perception for virtual rotations. Exp Gerontol. Sep. 2016;82:50\u0026ndash;7. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1016/j.exger.2016.05.014\u003c/span\u003e\u003cspan address=\"10.1016/j.exger.2016.05.014\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eBaloh RW, Jacobson KM, Socotch TM. The effect of aging on visual-vestibuloocular responses. Exp Brain Res. Aug. 1993;95(3). \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1007/BF00227144\u003c/span\u003e\u003cspan address=\"10.1007/BF00227144\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eHan BI, Song HS, Kim JS. Vestibular Rehabilitation Therapy: Review of Indications, Mechanisms, and Key Exercises. J Clin Neurol. 2011;7(4):184. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.3988/jcn.2011.7.4.184\u003c/span\u003e\u003cspan address=\"10.3988/jcn.2011.7.4.184\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eHaxby F, Akrami M, Zamani R. Finding a Balance: A Systematic Review of the Biomechanical Effects of Vestibular Prostheses on Stability in Humans. J Funct Morphol Kinesiol. Mar. 2020;5(2):23. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.3390/jfmk5020023\u003c/span\u003e\u003cspan address=\"10.3390/jfmk5020023\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eDlugaiczyk J, Gensberger KD, Straka H. Galvanic vestibular stimulation: from basic concepts to clinical applications, \u003cem\u003eJ. Neurophysiol.\u003c/em\u003e, vol. 121, no. 6, pp. 2237\u0026ndash;2255, Jun. 2019, \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1152/jn.00035.2019\u003c/span\u003e\u003cspan address=\"10.1152/jn.00035.2019\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eHerssens N, McCrum C. Stimulating balance: recent advances in vestibular stimulation for balance and gait. J Neurophysiol. Aug. 2019;122(2):447\u0026ndash;50. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1152/jn.00851.2018\u003c/span\u003e\u003cspan address=\"10.1152/jn.00851.2018\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eWhite O, Babič J, Trenado C, Johannsen L, Goswami N. The Promise of Stochastic Resonance in Falls Prevention. Front Physiol. Jan. 2019;9:1865. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.3389/fphys.2018.01865\u003c/span\u003e\u003cspan address=\"10.3389/fphys.2018.01865\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eLajoie K, Marigold DS, Vald\u0026eacute;s BA, Menon C. The potential of noisy galvanic vestibular stimulation for optimizing and assisting human performance. Neuropsychologia. Feb. 2021;152:107751. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1016/j.neuropsychologia.2021.107751\u003c/span\u003e\u003cspan address=\"10.1016/j.neuropsychologia.2021.107751\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eKwan A, Forbes PA, Mitchell DE, Blouin J-S, Cullen KE. Neural substrates, dynamics and thresholds of galvanic vestibular stimulation in the behaving primate, \u003cem\u003eNat. Commun.\u003c/em\u003e, vol. 10, no. 1, p. 1904, Apr. 2019. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1038/s41467-019-09738-1\u003c/span\u003e\u003cspan address=\"10.1038/s41467-019-09738-1\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eLopez C, Cullen KE. Electrical stimulation of the peripheral and central vestibular system, \u003cem\u003eCurr. Opin. Neurol.\u003c/em\u003e, vol. 37, no. 1, pp. 40\u0026ndash;51, Feb. 2024, \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1097/WCO.0000000000001228\u003c/span\u003e\u003cspan address=\"10.1097/WCO.0000000000001228\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003ede Pires APB, Silva TR, Torres MS, Diniz ML, Tavares MC, Gon\u0026ccedil;alves DU. Galvanic vestibular stimulation and its applications: a systematic review, \u003cem\u003eBrazilian Journal of Otorhinolaryngology\u003c/em\u003e, vol. 88. Elsevier Editora Ltda, pp. S202\u0026ndash;S211, Nov. 2022. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1016/j.bjorl.2022.05.010\u003c/span\u003e\u003cspan address=\"10.1016/j.bjorl.2022.05.010\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eFujimoto C, et al. Noisy galvanic vestibular stimulation induces a sustained improvement in body balance in elderly adults. Sci Rep. Nov. 2016;6(1):37575. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1038/srep37575\u003c/span\u003e\u003cspan address=\"10.1038/srep37575\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eAgrawal Y, Carey JP, Della Santina CC, Schubert MC, Minor LB. Disorders of Balance and Vestibular Function in US Adults: Data From the National Health and Nutrition Examination Survey, 2001\u0026ndash;2004. Arch Intern Med. May 2009;169(10):938. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1001/archinternmed.2009.66\u003c/span\u003e\u003cspan address=\"10.1001/archinternmed.2009.66\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eInukai Y, et al. Effect of noisy galvanic vestibular stimulation in community-dwelling elderly people: a randomised controlled trial. J Neuroeng Rehabil. Dec. 2018;15(1):63. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1186/s12984-018-0407-6\u003c/span\u003e\u003cspan address=\"10.1186/s12984-018-0407-6\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eAgrawal Y, Carey JP, Hoffman HJ, Sklare DA, Schubert MC, The Modified Romberg Balance Test: Normative Data in, Adults US. \u003cem\u003eOtol. Neurotol.\u003c/em\u003e, vol. 32, no. 8, pp. 1309\u0026ndash;1311, Oct. 2011, \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1097/MAO.0b013e31822e5bee\u003c/span\u003e\u003cspan address=\"10.1097/MAO.0b013e31822e5bee\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eCohen HS et al. Jun., Screening for Vestibular Disorders Using the Modified Clinical Test of Sensory Interaction and Balance and Tandem Walking With Eyes Closed, \u003cem\u003eOtol. Neurotol.\u003c/em\u003e, vol. 40, no. 5, pp. 658\u0026ndash;665, 2019, \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1097/MAO.0000000000002173\u003c/span\u003e\u003cspan address=\"10.1097/MAO.0000000000002173\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eNguyen TT, Kang J-J, Oh S-Y. Thresholds for vestibular and cutaneous perception and oculomotor response induced by galvanic vestibular stimulation. Front Neurol. Aug. 2022;13:955088. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.3389/fneur.2022.955088\u003c/span\u003e\u003cspan address=\"10.3389/fneur.2022.955088\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eInukai Y, et al. Effect of noisy galvanic vestibular stimulation in community-dwelling elderly people: a randomised controlled trial. J Neuroeng Rehabil. Dec. 2018;15(1):63. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1186/s12984-018-0407-6\u003c/span\u003e\u003cspan address=\"10.1186/s12984-018-0407-6\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eRalston JD, Raina A, Benson BW, Peters RM, Roper JM, Ralston AB. Physiological Vibration Acceleration (Phybrata) Sensor Assessment of Multi-System Physiological Impairments and Sensory Reweighting Following Concussion, \u003cem\u003eMed. Devices Evid. Res.\u003c/em\u003e, vol. Volume 13, pp. 411\u0026ndash;438, Dec. 2020, \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.2147/MDER.S279521\u003c/span\u003e\u003cspan address=\"10.2147/MDER.S279521\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eAbdollah V, Dief TN, Ralston J, Ho C, Rouhani H. Investigating the validity of a single tri-axial accelerometer mounted on the head for monitoring the activities of daily living and the timed-up and go test, \u003cem\u003eGait Posture\u003c/em\u003e, vol. 90, pp. 137\u0026ndash;140, Oct. 2021, \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1016/j.gaitpost.2021.08.020\u003c/span\u003e\u003cspan address=\"10.1016/j.gaitpost.2021.08.020\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eFiliatrault J, et al. Evidence of the Psychometric Qualities of a Simplified Version of the Activities-specific Balance Confidence Scale for Community-Dwelling Seniors. Arch Phys Med Rehabil. May 2007;88(5):664\u0026ndash;72. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1016/j.apmr.2007.02.003\u003c/span\u003e\u003cspan address=\"10.1016/j.apmr.2007.02.003\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eCarone D, Sherman A, Sep. Compendium of Neuropsychological Tests. : Fundamentals of neuropsychological assessment and test reviews for clinical practice (4th ed.), \u003cem\u003eAppl. Neuropsychol. Adult\u003c/em\u003e, vol. 31, pp. 1\u0026ndash;4, 2023, \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1080/23279095.2023.2260143\u003c/span\u003e\u003cspan address=\"10.1080/23279095.2023.2260143\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eWashburn RA, Smith KW, Jette AM, Janney CA. The physical activity scale for the elderly (PASE): Development and evaluation, \u003cem\u003eJ. Clin. Epidemiol.\u003c/em\u003e, vol. 46, no. 2, pp. 153\u0026ndash;162, Feb. 1993, \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1016/0895-4356(93)90053-4\u003c/span\u003e\u003cspan address=\"10.1016/0895-4356(93)90053-4\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eStewart WF, et al. An international study to assess reliability of the Migraine Disability Assessment (MIDAS) score. Neurology. 1999;53(5):988\u0026ndash;988. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1212/WNL.53.5.988\u003c/span\u003e\u003cspan address=\"10.1212/WNL.53.5.988\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eGrafton ST, Ralston AB, Ralston JD. Monitoring of postural sway with a head-mounted wearable device: effects of gender, participant state, and concussion. Med Devices Evid Res. May 2019;12:151\u0026ndash;64. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.2147/MDER.S205357\u003c/span\u003e\u003cspan address=\"10.2147/MDER.S205357\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eGoldberg JM, Smith CE, Fernandez C. Relation between discharge regularity and responses to externally applied galvanic currents in vestibular nerve afferents of the squirrel monkey, \u003cem\u003eJ. Neurophysiol.\u003c/em\u003e, vol. 51, no. 6, pp. 1236\u0026ndash;1256, Jun. 1984, \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1152/jn.1984.51.6.1236\u003c/span\u003e\u003cspan address=\"10.1152/jn.1984.51.6.1236\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eIwasaki S et al. Mar., Noisy vestibular stimulation improves body balance in bilateral vestibulopathy, \u003cem\u003eNeurology\u003c/em\u003e, vol. 82, no. 11, pp. 969\u0026ndash;975, 2014, \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1212/WNL.0000000000000215\u003c/span\u003e\u003cspan address=\"10.1212/WNL.0000000000000215\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eGensberger KD, et al. Galvanic Vestibular Stimulation: Cellular Substrates and Response Patterns of Neurons in the Vestibulo-Ocular Network. J Neurosci. Aug. 2016;36:9097\u0026ndash;110. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1523/JNEUROSCI.4239-15.2016\u003c/span\u003e\u003cspan address=\"10.1523/JNEUROSCI.4239-15.2016\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eGroves AK. The challenge of hair cell regeneration, \u003cem\u003eExp. Biol. Med. Maywood NJ\u003c/em\u003e, vol. 235, no. 4, pp. 434\u0026ndash;446, Apr. 2010, \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1258/ebm.2009.009281\u003c/span\u003e\u003cspan address=\"10.1258/ebm.2009.009281\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eGrassi S, Frondaroli A, Pettorossi VE. Different Metabotropic Glutamate Receptors Play Opposite Roles in Synaptic Plasticity of the Rat Medial Vestibular Nuclei, \u003cem\u003eJ. Physiol.\u003c/em\u003e, vol. 543, no. 3, pp. 795\u0026ndash;806, Sep. 2002, \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1113/jphysiol.2002.023424\u003c/span\u003e\u003cspan address=\"10.1113/jphysiol.2002.023424\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eSmith PF, Curthoys IS. following unilateral labyrinthectomy: a review.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eDutia MB. Mechanisms of vestibular compensation: recent advances. Curr Opin Otolaryngol Head Neck Surg. Oct. 2010;18(5):420\u0026ndash;4. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1097/MOO.0b013e32833de71f\u003c/span\u003e\u003cspan address=\"10.1097/MOO.0b013e32833de71f\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eHelmchen C, Rother M, Spliethoff P, Sprenger A. Increased brain responsivity to galvanic vestibular stimulation in bilateral vestibular failure. NeuroImage Clin. 2019;24:101942. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1016/j.nicl.2019.101942\u003c/span\u003e\u003cspan address=\"10.1016/j.nicl.2019.101942\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eAlvarez JC et al. Apr., Aging and the human vestibular nuclei: morphometric analysis, \u003cem\u003eMech. Ageing Dev.\u003c/em\u003e, vol. 114, no. 3, pp. 149\u0026ndash;172, 2000, \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1016/S0047-6374(00)00098-1\u003c/span\u003e\u003cspan address=\"10.1016/S0047-6374(00)00098-1\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eSung P, Rowland P. Impact of sensory reweighting strategies on postural control using the sensory organization test in older adults with and without fall risks, \u003cem\u003ePhysiother. Res. Int.\u003c/em\u003e, vol. 29, no. 2, p. e2075, Apr. 2024. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1002/pri.2075\u003c/span\u003e\u003cspan address=\"10.1002/pri.2075\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eUtz KS et al. Oct., Minor adverse effects of galvanic vestibular stimulation in persons with stroke and healthy individuals, \u003cem\u003eBrain Inj.\u003c/em\u003e, vol. 25, no. 11, pp. 1058\u0026ndash;1069, 2011, \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.3109/02699052.2011.607789\u003c/span\u003e\u003cspan address=\"10.3109/02699052.2011.607789\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eCavin ID, Glover PM, Bowtell RW, Gowland PA. Thresholds for perceiving metallic taste at high magnetic field, \u003cem\u003eJ. Magn. Reson. Imaging\u003c/em\u003e, vol. 26, no. 5, pp. 1357\u0026ndash;1361, Nov. 2007, \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1002/jmri.21153\u003c/span\u003e\u003cspan address=\"10.1002/jmri.21153\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e\u003c/ol\u003e"},{"header":"Tables","content":"\u003cp\u003eTable 1 is available in the Supplementary Files section.\u003c/p\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":true,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"journal-of-neuroengineering-and-rehabilitation","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"jner","sideBox":"Learn more about [Journal of NeuroEngineering and Rehabilitation](http://jneuroengrehab.biomedcentral.com/)","snPcode":"12984","submissionUrl":"https://submission.nature.com/new-submission/12984/3","title":"Journal of NeuroEngineering and Rehabilitation","twitterHandle":"@BioMedCentral","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"BMC/SO AJ","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"Vestibular System, Balance Control, Aging, Electrical Vestibular Stimulation, Galvanic Vestibular Stimulation, Postural Sway, Vestibular Therapy, Balance Therapy","lastPublishedDoi":"10.21203/rs.3.rs-6349795/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-6349795/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003ch2\u003eBackground\u003c/h2\u003e \u003cp\u003eFalls are the leading cause of injury-related hospitalizations among older adults, often linked to vestibular dysfunction. While vestibular rehabilitation therapy is a standard intervention, designed to compensate for vestibular impairment with proprioceptive and visual ques, potential cumulative effects of Electrical Vestibular Stimulation (EVS) on balance improvement in older adults are not well understood.\u003c/p\u003e\u003ch2\u003eObjective\u003c/h2\u003e \u003cp\u003eThis study evaluated the efficacy of cumulative EVS dosing in improving static balance, its potential mechanisms, and clinical significance.\u003c/p\u003e\u003ch2\u003eMethods\u003c/h2\u003e \u003cp\u003eA single-blind, randomized controlled trial enrolled 40 older adults (mean age: 77.7\u0026thinsp;\u0026plusmn;\u0026thinsp;11.8 years). Participants were randomly assigned to a Stimulation group (EVS intervention) or Sham group. The EVS regimen included low-amplitude wideband stimulation (\u0026plusmn;\u0026thinsp;0.35 mA, 0\u0026ndash;300 Hz) for 20 minutes, three times weekly for six weeks. Balance performance was assessed using a head-mounted sensor to measure postural sway (\u0026lsquo;phybrata\u0026rsquo;) power in four static conditions: Floor EO, Floor EC, Foam EO, and Foam EC. Follow-ups occurred at 3 months and 6 months post-intervention.\u003c/p\u003e\u003ch2\u003eResults\u003c/h2\u003e \u003cp\u003eThe Stimulation group exhibited significant and sustained reductions in phybrata power, particularly in Foam EO and Foam EC conditions, with improvements observed as early as Day 3 and persisting through 6 months. Additionally, the Sham group demonstrated smaller reductions in phybrata power, potentially reflecting a learning effect.\u003c/p\u003e\u003ch2\u003eConclusion\u003c/h2\u003e \u003cp\u003eEVS is a safe and effective intervention for improving balance in older adults. Its benefits in addressing age-related deficits in balance and sensory integration highlight its potential for fall prevention and rehabilitation.\u003c/p\u003e","manuscriptTitle":"Electrical vestibular stimulation to improve static balance in older adults: a randomized control trial","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-05-29 15:54:35","doi":"10.21203/rs.3.rs-6349795/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2025-06-02T08:01:21+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-05-30T16:44:00+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-05-18T17:42:40+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-05-14T19:49:39+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"133303579157344964052050671507736785477","date":"2025-05-05T18:04:43+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"336932548075400112467742233372376693647","date":"2025-05-01T21:03:29+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"87390331431725872388646450973768584419","date":"2025-04-24T17:41:11+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2025-04-06T08:56:45+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2025-04-02T04:58:17+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2025-04-02T04:53:35+00:00","index":"","fulltext":""},{"type":"submitted","content":"Journal of NeuroEngineering and Rehabilitation","date":"2025-04-01T05:50:31+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"journal-of-neuroengineering-and-rehabilitation","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"jner","sideBox":"Learn more about [Journal of NeuroEngineering and Rehabilitation](http://jneuroengrehab.biomedcentral.com/)","snPcode":"12984","submissionUrl":"https://submission.nature.com/new-submission/12984/3","title":"Journal of NeuroEngineering and Rehabilitation","twitterHandle":"@BioMedCentral","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"BMC/SO AJ","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"255f0132-e3c0-4134-b9ac-b5a01e807e08","owner":[],"postedDate":"May 29th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"published-in-journal","subjectAreas":[],"tags":[],"updatedAt":"2025-11-03T16:02:05+00:00","versionOfRecord":{"articleIdentity":"rs-6349795","link":"https://doi.org/10.1186/s12984-025-01749-y","journal":{"identity":"journal-of-neuroengineering-and-rehabilitation","isVorOnly":false,"title":"Journal of NeuroEngineering and Rehabilitation"},"publishedOn":"2025-10-31 15:58:06","publishedOnDateReadable":"October 31st, 2025"},"versionCreatedAt":"2025-05-29 15:54:35","video":"","vorDoi":"10.1186/s12984-025-01749-y","vorDoiUrl":"https://doi.org/10.1186/s12984-025-01749-y","workflowStages":[]},"version":"v1","identity":"rs-6349795","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-6349795","identity":"rs-6349795","version":["v1"]},"buildId":"XKTyCvWXoU3ODBz1xrDgd","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}