Effects of Combined Transcranial Direct Current Stimulation and Collaborative Robot-Assisted Therapy on Upper Limb Function: A Unilateral Pontine Stroke Case Study

Effects of Combined Transcranial Direct Current Stimulation and Collaborative Robot-Assisted Therapy on Upper Limb Function: A Unilateral Pontine Stroke Case Study | 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 Case Report Effects of Combined Transcranial Direct Current Stimulation and Collaborative Robot-Assisted Therapy on Upper Limb Function: A Unilateral Pontine Stroke Case Study Henrique Santos, Carlos Campos, Eduardo Lattari, Paulo Abreu, and 3 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-8740414/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract Introduction: Unilateral pontine stroke can impair upper limb motor function due to damage in brainstem motor pathways. An emerging intervention approach proposes the combination of neuroplasticity-inducing techniques such as transcranial direct current stimulation (tDCS) with task-specific training exercises like robot-assisted therapy. Objective: To examine the effects of primary motor cortex dual-tDCS (excitatory ipsilesional and inhibitory contralesional) combined with collaborative robot-assisted therapy on hand/upper limb motor function and fatigue of a patient with unilateral chronic pontine stroke. Methodology: A 10-session protocol combining dual-tDCS with a collaborative robot-assisted upper limb exercises was employed. Outcome measures (assessed pre-intervention, mid-intervention, post-intervention, and 1-month follow-up) included hand/upper limb motor function (manual dexterity, hand grip strength, motor reaction time, shoulder flexion range of motion) and perceived physical and mental fatigue. A structured interview was conducted to capture the participant’s subjective perception of improvement. Results: The patient showed significant post-intervention improvements in manual dexterity, shoulder flexion range of motion, and hand grip strength, while also displaying reduction in physical fatigue. These results were largely retained after the 1-month follow-up period. The structured interview indicated that the patient reported greater participation in daily activities, with less perceived fatigue. Conclusion: The combination of dual-tDCS with robot-assisted therapy in a patient with unilateral chronic pontine stroke demonstrated positive effects on hand/upper limb motor function as well as on physical fatigue. This intervention protocol may be a useful and engaging complementary rehabilitation approach for several stroke subtypes. Physical Medicine & Rehab Stroke Current Stimulation Robot Hand Motor Full Text Additional Declarations The authors declare potential competing interests as follows: LabRP/CIR is currently engaged in a paid scientific and technical consultancy on non-invasive brain stimulation with a private healthcare enterprise. The present study was neither designed nor conducted within the scope of this collaboration. Cite Share Download PDF Status: Posted Version 1 posted 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. 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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-8740414","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Case Report","associatedPublications":[],"authors":[{"id":583015199,"identity":"5e175e4f-5023-4b70-b58e-942f4b650e5d","order_by":0,"name":"Henrique Santos","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAAqklEQVRIiWNgGAWjYBACAwYGxgcgBhspWpgNEFoSiNPCJoHgEqPFnP34s4oPf+oY+KR7DzAX/iBCi2VPjtnNmW2HGdhkziUwzyDKYQdy2G7zNhwAOi/HgJmHKC3nnz8r/gN0GAlabiSYMTOwMZOk5Y2xZG/bYR6QXw7PSCPKYekPP/z4UycnP7v34OMCGyK0wAAPgwQPw2ESNIAAUAsziVpGwSgYBaNghAAAGQswurXp8zsAAAAASUVORK5CYII=","orcid":"https://orcid.org/0009-0009-4683-5066","institution":"E2S, Polytechnic of Porto","correspondingAuthor":true,"prefix":"","firstName":"Henrique","middleName":"","lastName":"Santos","suffix":""},{"id":583015200,"identity":"3042b659-3c03-46ef-94af-ca93f389320f","order_by":1,"name":"Carlos Campos","email":"","orcid":"","institution":"LabRP/CIR, E2S, Polytechnic of Porto","correspondingAuthor":false,"prefix":"","firstName":"Carlos","middleName":"","lastName":"Campos","suffix":""},{"id":583015201,"identity":"7a65f79e-5a36-4648-a7fe-236cea3ef412","order_by":2,"name":"Eduardo Lattari","email":"","orcid":"","institution":"Salgado de Oliveira University (UNIVERSO)","correspondingAuthor":false,"prefix":"","firstName":"Eduardo","middleName":"","lastName":"Lattari","suffix":""},{"id":583015202,"identity":"11c5fd30-9b91-44c1-ab99-e194f7f036cb","order_by":3,"name":"Paulo Abreu","email":"","orcid":"","institution":"LAETA INEGI Institute of Science and Innovation in Mechanical and Industrial Engineering","correspondingAuthor":false,"prefix":"","firstName":"Paulo","middleName":"","lastName":"Abreu","suffix":""},{"id":583015203,"identity":"65a48e53-5ca0-490f-98fe-9480fb2cf517","order_by":4,"name":"Paula Portugal","email":"","orcid":"","institution":"- LabRP/CIR, E2S, Polytechnic of Porto","correspondingAuthor":false,"prefix":"","firstName":"Paula","middleName":"","lastName":"Portugal","suffix":""},{"id":583015204,"identity":"53bc0897-a3fa-45b8-bc56-2ae14211f9ae","order_by":5,"name":"Teresa Restivo","email":"","orcid":"","institution":"LAETA INEGI Institute of Science and Innovation in Mechanical and Industrial Engineering","correspondingAuthor":false,"prefix":"","firstName":"Teresa","middleName":"","lastName":"Restivo","suffix":""},{"id":583015205,"identity":"278246a2-9150-4f9d-b879-8402ec87f951","order_by":6,"name":"Helena Sousa","email":"","orcid":"","institution":"CIR, E2S, Polytechnic of Porto","correspondingAuthor":false,"prefix":"","firstName":"Helena","middleName":"","lastName":"Sousa","suffix":""}],"badges":[],"createdAt":"2026-01-30 11:22:51","currentVersionCode":1,"declarations":{"humanSubjects":true,"vertebrateSubjects":false,"conflictsOfInterestStatement":true,"humanSubjectEthicalGuidelines":true,"humanSubjectConsent":true,"humanSubjectClinicalTrial":false,"humanSubjectCaseReport":true,"vertebrateSubjectEthicalGuidelines":false},"doi":"10.21203/rs.3.rs-8740414/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-8740414/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":101752988,"identity":"101c7a5b-7ace-4cc1-9da5-4e4d13001dd8","added_by":"auto","created_at":"2026-02-03 10:38:39","extension":"pdf","order_by":1,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":644843,"visible":true,"origin":"","legend":"","description":"","filename":"Santosetal.2026PrePrint.pdf","url":"https://assets-eu.researchsquare.com/files/rs-8740414/v1_covered_d70b8569-2dc5-440d-afa4-f01192fb970b.pdf"}],"financialInterests":"The authors declare potential competing interests as follows: LabRP/CIR is currently engaged in a paid scientific and technical consultancy on non-invasive brain stimulation with a private healthcare enterprise. 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An emerging intervention approach proposes the combination of neuroplasticity-inducing techniques such as transcranial direct current stimulation (tDCS) with task-specific training exercises like robot-assisted therapy.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eObjective: \u003c/strong\u003eTo examine the effects of primary motor cortex dual-tDCS (excitatory ipsilesional and inhibitory contralesional) combined with collaborative robot-assisted therapy on hand/upper limb motor function and fatigue of a patient with unilateral chronic pontine stroke.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eMethodology: \u003c/strong\u003eA 10-session protocol combining dual-tDCS with a collaborative robot-assisted upper limb exercises was employed. Outcome measures (assessed pre-intervention, mid-intervention, post-intervention, and 1-month follow-up) included hand/upper limb motor function (manual dexterity, hand grip strength, motor reaction time, shoulder flexion range of motion) and perceived physical and mental fatigue. A structured interview was conducted to capture the participant’s subjective perception of improvement.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eResults:\u003c/strong\u003e The patient showed significant post-intervention improvements in manual dexterity, shoulder flexion range of motion, and hand grip strength, while also displaying reduction in physical fatigue. These results were largely retained after the 1-month follow-up period. The structured interview indicated that the patient reported greater participation in daily activities, with less perceived fatigue.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConclusion:\u003c/strong\u003e The combination of dual-tDCS with robot-assisted therapy in a patient with unilateral chronic pontine stroke demonstrated positive effects on hand/upper limb motor function as well as on physical fatigue. This intervention protocol may be a useful and engaging complementary rehabilitation approach for several stroke subtypes.\u003c/p\u003e","manuscriptTitle":"Effects of Combined Transcranial Direct Current Stimulation and Collaborative Robot-Assisted Therapy on Upper Limb Function: A Unilateral Pontine Stroke Case Study","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2026-02-02 04:47:26","doi":"10.21203/rs.3.rs-8740414/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"852a70d7-6c07-42a2-b962-d748548a1c10","owner":[],"postedDate":"February 2nd, 2026","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[{"id":62026693,"name":"Physical Medicine \u0026 Rehab"}],"tags":[],"updatedAt":"2026-02-02T04:47:26+00:00","versionOfRecord":[],"versionCreatedAt":"2026-02-02 04:47:26","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-8740414","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-8740414","identity":"rs-8740414","version":["v1"]},"buildId":"XKTyCvWXoU3ODBz1xrDgd","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}