Enhancing Task Persistence in 18- to 24-Month-Old Children through Social Robot Interaction

Enhancing Task Persistence in 18- to 24-Month-Old Children through Social Robot Interaction | 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 Enhancing Task Persistence in 18- to 24-Month-Old Children through Social Robot Interaction Mikako Ishibashi, Yuta Shinya, Yuichiro Yoshikawa, Hiroshi Ishiguro, and 1 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-6301569/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 Social robots are increasingly integrated into children's daily lives, shaping their social interactions and learning behaviors. However, no study has empirically investigated the effect of robot-administered praise on children younger than 4 years old. To address this gap, the present study focuses on social robot CommU, a simple child-shaped robot that is approximately 30 cm tall, which may exert less social pressure and help children attend to social cues more easily. We examined whether praise from the CommU enhances task persistence in children aged 18 to 24 months, similar to human praise. The results showed that children persisted longer when they were praised by the agent, regardless of the agent type (CommU vs. human). Their persistence was also positively associated with the amount of time they spent looking at the agent. Notably, most of the children exhibited attention to the CommU while engaged in the task, suggesting their heightened social awareness. These findings provide the first empirical evidence that social robot interaction can enhance task persistence in children aged 18 to 24 months, highlighting the potential role of social robots in early childhood learning. Robotics Psychology CommU robot Toddlers (18 to 24 months) persistence praise effect look Figures Figure 1 Figure 2 1. Introduction Social robots, defined as robots that can interact socially and communicate with humans and other autonomous physical entities [ 1 ], are being introduced into children's daily lives [ 2 – 5 ], with their presence in homes and classrooms expected to increase rapidly [ 6 – 8 ]. There are various types of social robots, including androids, dolls, and animal-like designs, each capable of eliciting beneficial social behaviors in children [ 9 – 11 ]. In particular, when robots respond appropriately to children's actions and words [ 12 ], behave like friends [ 13 ], or express emotions [ 14 ], they are more likely to perceive them as social beings. Kumazaki et al. [ 15 ] suggested that when social robots are introduced to young children, robots with small sizes and simple designs may be preferred. CommU (Vstone Co., Ltd.) is a relatively simple robot that lacks a human-like appearance but has a child-like form and is approximately 30 cm tall [ 16 ]. Considering the CommU's design is simple, it conveys less information than Android robots and is less likely to create social pressure, allowing users to focus more on social cues [ 17 ]. Several studies have demonstrated that CommUs are effective at promoting social communication. For instance, conversations with CommU facilitate self-disclosure among users [ 16 ]. Moreover, individuals with ASD felt more comfortable communicating with CommU than with humans [ 18 ], suggesting that CommU may be useful in fostering relationships and providing psychological support. Furthermore, CommU has been applied in learning support, with training via CommU improving joint attention (JA) in children, leading to enhanced performance in subsequent JA tasks with humans [ 19 ]. Thus, the CommU has proven an effective tool for supporting children's learning. One specific type of supporting children’s social learning that social robots can provide is praise. Shiomi et al. [ 20 ] examined the effects of praise received from two robots on children's learning. Praise is a fundamental social reward that motivates young children to achieve their goals and fosters their desire to learn [ 21 ]. Shiomi et al. [ 20 ] compared the duration of English learning sessions among children aged 4 to 6 under two conditions: when one robot praised them versus when two robots praised them. The results showed that when two robots praised the children, they spent significantly more time learning English than when only one robot praised them. This study suggests that praise from robots can encourage learning persistence in young children. Similar to Shiomi et al. [ 20 ], other studies have examined the effects of robot-administered praise [ 22 , 24 ]; however, all these studies focused on school-aged or older children. Collecting sufficient research data on robots interacting with children under four years old is challenging due to their strong resistance to robots [ 18 ]. Consequently, except for Tanaka et al. [ 25 ], few studies have explored the interactions between robots and typically developing children aged one or two years. Tanaka et al. [ 25 ] placed a robot in a nursery room for children aged 18–24 months over a five-month period. The robot (QRIO) used in this study was relatively small (58 cm tall), and its facial structure was similar to that of the CommU, with cameras mounted above both eyes. The robot was programmed to provide contingent responses to the children over 45 sessions, leading to improved child–robot interaction quality, including caretaking behavior and conversation, over time. These findings suggest that even children as young as 18–24 months can establish social interactions with robots. However, to the best of our knowledge, no studies have empirically investigated the effects of robot-administered praise on toddlers (18–24 months). The effects of praise on children aged one to two years were examined from the perspective of task persistence. Lucca et al. [ 26 ] conducted an experiment to investigate the impact of parental encouragement on children aged 18–24 months. The results showed that children who received process-focused praise from their parents spent more time working on tasks than those who did not receive praise [ 26 ]. Additionally, Radovanovic et al. [ 27 ] found that children's (17–31 months) persistence was maximized when parental praise was timed to coincide with their engagement in the task. With regard to early expressions of persistence, it should be noted that they are widely influenced by interactions with the social environment [ 28 , 29 ]. Recent research has shown that infants’ behavioral and attentional persistence may be enhanced when infants observe persistence in others [ 30 , 31 ]. Therefore, the effects of praise on children's persistence may also depend on their awareness of others as social beings. For example, Okumura et al. [ 32 ] found that five-year-olds who were observed by a social interactive robot shared more stickers than those interacting with an attentional but non-interactive or stationary robot, suggesting that five-year-olds adjust their own behaviour based on whether or not the other is a social being. However, it remains unclear whether social awareness of the robot presence enhances young children's persistence. In this study, we experimentally investigated whether the praise of the social robot CommU could enhance the persistence of young children aged18–24 months in the same way as human praise. As it has been suggested that young children preferred the small sized robot [ 15 ], we considered that CommU to be appropriate for 18–24 months in this study. Also, Kumazaki et al. [ 18 ] pointed out that CommU has a high degree of eye movement flexibility, indicating that it easily captures users' attention from children. Given that parental encouragement has been shown to enhance task persistence in children aged 18 to 24 months [ 26 ] and that young children perceive robots as social beings [ 25 ], we hypothesized that the praise from CommU would contribute to children's task persistence in a manner similar to human praise. Furthermore, we investigated whether looking toward CommU would be associated with the persistence of young children, considering social awareness of the robot would adjust their social behavior (e.g., [ 32 ]). 2. Method 2.1. Participants Following a previous study [ 26 ], we recruited children aged 18–24 months. 86 18–24 months participated in this study. Fourteen out of 86 children were excluded for the following reasons: (1) children could not perform the task itself because of fear of the CommU ( n = 2); (2) children were not motivated to participate or remained clinging to their mother for 2 min ( n = 7); and (3) experimental error in the procedure ( n = 5). The sample size estimation required 32 participants per condition and the study was terminated when 32 children participated. However, 8 children were excluded during the coding because they did not engage in the entire persistent task. The final number of participants used in the analysis was 58 (30 girls; mean age = 20.79 months, SD = 2.05). The CommU condition included 30 participants (mean age = 20.87 months, SD = 2.36) and the Human condition included 28 participants (mean age = 20.71 months, SD = 1.70). This study was approved by the ethical committee of the Doshisha University(number: 20029). 2.2. Stimuli A toy with stacked gears was used in a previous study [ 26 ]. This toy comprised a bar with a base and six disks that could be stacked on top. A sponge was glued to the center of the disk or a rubber band was glued to the disk to prevent stacking. 2.3. Procedure 2.3.1. Experimental Setup In the CommU condition, the child, his/her mother, an experimental assistant, and the CommU were in an experimental room. First, before the task was conducted, we allowed sufficient time (approximately 10–20 min) for interaction with the CommU for the children to relax. None of the children who participated in the experiment had previously interacted with the CommU, and the experimental assistant provided support to facilitate the interaction among the CommU, mother, and child. After confirming that the child was familiar with the CommU (e.g., talking to, laughter, or touching the CommU), the experimental assistant prepared the tools used in the persistent task. In the Human condition, the child and her mother were escorted by the experimental assistant into the experimental room. 2.4. Persistent task We set two conditions under which the agent praised or did not praise the child. The with/without praise condition was a within-participant design, and the order of the conditions was randomized between the participants. The agent, CommU/Human, was between the participant designs. 2.4.1. Demonstration of the task First, the experimenter said, " x-chan [child’s name], look", to draw the child's attention, and then demonstrated how to remove the sponge from the disk and insert the disk into the bar. The experimenter then handed another disk to the child and said, "Here you go, [the child’s name]”. After the child received the disk, the time was measured for 2 min and the child's behavior was observed. To play with the toy, the child needed to insert the disk in the center into the stick; however, the disk glued to sponges or rubber bands could not be inserted. The order of the sponges and rubber bands was presented randomly. 2.5. CommU condition 2.5.1. Praise condition The CommU praised the child every 10 s after the disk was handed to him/her. The timing of praise was fixed at every 10 s for 2 min. Praise was given in the following order: "[child’s name], you are doing well", "[child’s name], you are looking good", and "[child’s name], you are doing well". In Shiomi's study [ 20 ], a human operator was incorporated into the system to control the timing of the robot's actions because children behaved unexpectedly. As in Shiomi [ 20 ], the timing of the praise was fixed (praising once every 10 s). We selected sentences that were not unnatural, even when the child was attempting to perform an unattainable task. The operator remotely controlled the CommU and moved the CommU’s face and body appropriately in response to the child’s movements. After 2 min, the experimenter again drew the child's attention and handed the child a disk that could be inserted into the stick to reduce frustration. 2.5.2. No Praise condition The disks and sticks with bases used in the praise condition were removed, and new disks and sticks with bases were placed on the floor. The disks had a rubber band attached to them, and the experimenter demonstrated by showing the removal of the rubber band attached to the disk. The measurements began after the child was provided with a disk. As in the praise condition, the face and body moved in accordance with the child's movements. 2.6. Human condition 2.6.1. Praise condition A human praised the child every 10 s after handling the disk. The lines and order of praise were the same as in the CommU condition. After 2 min, the experimenter again drew the child’s attention and handed them a disk they could insert into the stick to reduce frustration. 2.6.2. No Praise condition The disks and sticks used in the praise condition were removed, and new disks and sticks with bases were placed. The disks had a rubber band attached to them, and the experimenter demonstrated by showing the removal of the rubber band attached to the disks. The measurements began after the disks were handed over to the children. As in the praise condition, the face and body moved according to the child's movements. 2.7. Coding schema 2.7.1. Trying Children’s persistence was measured as described by Lucca et al [ 26 ]. We named it “Trying,” and the following two behaviors were measured: (1) Inserting disk into stick: Trying was coded when the disk was placed at the tip of the stick. The start time was when the child was placed on the disk at the tip of the stick, and the end time was when the disk left the tip of the stick. (2) Removal of sponge/rubber band from disks: The time at which each child attempted to remove the sponge or rubber band glued to a disk was recorded. The start time was when the child was trying to put his/her finger on the sponge or remove the rubber band, and the end time was when the child's finger left the disk. 2.7.2. Look We counted the duration of the children’s looking time in the CommU/Human condition. Looking was counted when the child looked at the CommU (in the CommU condition) or human (in the Human condition) for at least 1 s. 3. Results Descriptive statistics are shown for each agent with and without praise (Table 1 ). We also show the mean time spent trying between the no praise and praise conditions for each agent (Fig. 1 ). Table 1 Mean and standard deviation of Trying and Look with/without praise per Agent. Agent Condition Mean of Trying ( SD ) Mean of Look ( SD ) CommU No praise 26.3 (27.31) 12.01 (11.97) CommU Praise 32.22 (27.48) 11.86 (10.1) Human No praise 21.04 (26.42) 7.84 (7.35) Human Praise 24.91 (23.28) 8.00 (8.7) We measured looking during the task and examined the relationship between the length of looking and trying using correlation analysis. In the CommU condition, correlation analysis revealed no significant correlation between trying and looking in the praise condition ( r = 0.10, p = .59) and in the no praise condition ( r = 0.35, p = .06). In the Human condition, the correlation analysis revealed a significant correlation between trying and Look in the praise condition ( r = 0.58, p = .00) and in the no praise condition ( r = 0.71, p = .00). 3.1 Analysis We conducted linear mixed-effects models (LMMs) using the lmer function from the lme4 package in R [ 33 ] to examine the effects of age, sex, Condition (praise/no praise), Look, and Agent (CommU/Human) on Trying behavior. We included the participants as random intercepts to account for individual differences. Age and Look variables were standardized using z-scores. Model 1 was explained as a baseline model to assess the effects of standardized age and sex on trying behaviors. A random intercept for the participants (ID) was included as an individual difference. Model 2 was extended to Model 1 by adding the condition (praise/no praise), Standardized Look, and Agent (CommU/Human) as fixed effects. Model 3 further explained the interaction to examine the effects of Condition and Look on the agent’s trying behavior. Each model is described in detail in the Appendix. The LMM results are shown in Table 2 . In Model 1, standardized age was positively associated with trying ( B = 8.06, SE = 3.11, t = 2.59, p = .01), while sex did not show a significant effect ( B = -7.18, SE = 6.22, t = -1.16, p = .25). In Model 2, standardized age remained significant ( B = 7.15, SE = 2.83, t = 2.53, p = .01). In addition, condition and looking behavior were significant predictors of trying (Condition: B = 5.09, SE = 2.45, t = 2.08, p = .04, Look: B = 10.61, SE = 2.93, t = 3.62, p = .00). Model 3 showed that standardized age, condition, and looking behavior remained significant predictors of trying (Standardized Age: B = 6.58, SE = 2.82, t = 2.34, p = .02; Look: B = 7.29, SE = 3.59, t = 2.03, p = .05). The effect of the condition was marginally significant ( B = 6.24, SE = 3.43, t = 1.82, p = .07). There was no significant interaction effect between the Agent and Condition, and between Agent and Look. All the interactions between the Condition and Agent ( p = .63) and between the Look and the Agent ( p = .13) were not significant, and the main effect of the condition, which was significant in Model 2, became a significant trend ( p = .07). The likelihood ratio test indicated that Model 2 exhibited significantly improved fit compared to Model 1 (χ²(3) = 17.79, p < .001). However, no significant effect between Model 2 and Model 3 (χ²(2) = 2.87, p = .24), suggesting that the effect of interaction of Model 3 did not improve significantly. In addition, the models showed the lowest AIC ( AIC = 1034), indicating that Model 2 was the best-fit model among other models. Table 2 Results of comparison of LMM models Model 1 Model 2 Model 3 Predictors B 95%CI P B 95%CI P B 95%CI P (Intercept) 29.78 21.24–38.31 < 0.001 26.08 16.45–35.72 < 0.001 26.01 16.18–35.84 < 0.001 Standardized Age 8.06 1.90–14.22 0.011 7.15 1.54–12.76 0.013 6.58 0.99–12.16 0.021 Sex [m] -7.18 − 19.46–5.10 0.249 -4.17 -15.45–7.10 0.465 -3.59 − 14.74–7.57 0.525 Condition [Praise] 5.09 0.23–9.95 0.040 6.24 -0.57–13.04 0.072 Standardized Look 10.61 4.80–16.41 < 0.001 7.29 0.18–14.41 0.045 Agent [human] -0.63 -12.10–10.85 0.914 1.16 -11.21–13.52 0.853 Condition [Praise] x Agent [human] -2.37 − 12.17–7.42 0.632 Agent [human] x Standardized Look 9.34 -2.57–21.26 0.123 Observations 116 116 116 Marginal R 2 / Conditional R 2 0.108 / 0.746 0.264 / 0.764 0.287 / 0.764 AIC 1046 1034 1035 4. Discussion The purpose of this study was to empirically verify whether children 18–24 months would increase their persistence in task-related behavior when praised by the social robot CommU, in the same way as when praised by a human. We examined the effects of condition (praise/no praise), agent (CommU/human), and gaze duration (children’s looking time at the agent) as predictors of children's persistence in their tasks. In the LMM model, we found that age, condition, and gaze duration were significant predictors of persistence. Specifically, we observed that persistence increased with age and was enhanced by both praise and longer gaze duration directed at the agent. Furthermore, the duration of persistence was longer when the child received praise compared to when they did not. Neither the agent-condition interaction nor the gaze-condition interaction was significant, suggesting that the effects of praise and gaze behavior independently influence children's task persistence. Our results indicate that the praise of CommU could enhance task persistence of children aged 18–24 months. This is consistent with previous research [ 26 ], which found that young children who received parental praise persisted in their tasks for longer. It also aligns with Shiomi et al. [ 20 ], who demonstrated that children aged 5 to 6 years spent more time working on a task when encouraged by social robots. Interestingly, our study revealed that praise from CommU sustained children's persistent behavior compared to a situation without praise. This suggests that even children as young as 18–24 months may perceive CommU as a social being and respond to its social signals. In addition, regardless of whether CommU provided praise, children were drawn to the robot, leading them to look at it. Okumura et al. [ 32 ] found that 5-year-olds engaged in strategic reputation management by sharing more stickers when observed by a social robot compared to a non-interactive robot. This suggests that presence of robot elicit social awareness, influencing children’s social behavior. Similarly, Kumazaki et al. [ 18 ] noted that CommU’s high degree of eye movement freedom naturally draws user attention. Anzalone et al. [ 37 ] used the Nao robot—a design relatively similar to CommU—to train children with ASD and found that JA scores in ASD children significantly decreased when using Nao. Since Nao's eyes are smaller than CommU’s, children with ASD may have focused on non-eye-related features of Nao [ 38 ]. Considering these studies, it is possible that CommU's eye features increased children's social awareness, contributing to their engagement in the task. A significant age effect was also observed, consistent with Radovanovic et al. [ 27 ], who demonstrated a linear relationship between age and engagement in a task among children aged 17 to 31 months. Previous studies suggest that as children aged one to two years grow older, they develop greater effortful control [ 34 – 36 ]. Therefore, task persistence could be assumed to be related to age in children of this age group. Previous studies suggested that young children prefer small and simply designed robots [ 15 ]. Additionally, children aged 1–2 years, with fewer preconceptions about robots, may engage in more fundamental social interactions that do not rely on advanced conversation [ 25 ]. Tanaka et al. [ 25 ] used a small, simple-faced robot (QRIO) to investigate qualitative changes in interactions with children aged 18–24 months over four months. They found that robots with simpler appearances allowed children to focus more on social cues because processing excessive visual information can be challenging at this age [ 15 ]. Similarly, in the present study, the CommU’s simple design may have allowed children to focus on social cues such as praise and gaze. Communication with robots, less complex than with humans, is processed at an "intermediate difficulty" level, making robot interactions more accessible to young children [ 39 ]. To further investigate these considerations, future research should examine the persistence of children aged18–24 months using robots other than the CommU. One limitation of this study is that we could not conclusively determine whether the social reward of praise from CommU directly increased children's persistence. Lucca et al. [ 26 ] argued that process-oriented praise teaches children the importance of their efforts. However, whether the effect observed in our study was due to process-oriented vocalizations or simply the presence of vocal praise remains unclear. Future research should include control conditions in which the CommU provides meaningless utterances during tasks to isolate the effects of praise as a social reward. Additionally, as in previous studies, predicting young children's responses was difficult; therefore, we did not implement contingent responses [ 20 ]. In this study, praise was not provided contingently to avoid cases in which children assigned to the praise condition did not engage with the disc and, therefore, would not receive praise. Prior research suggests that praise timing matters; praise given during a behavior is more effective in increasing persistence than praise given after [ 27 ]. Future studies could compare a randomly moving robot with one that provides contingent praise based on children's responses. Moreover, in this study, the experiments began only after confirming that the children had become familiar with CommU (e.g., a child speaking CommU). However, previous research suggests that young children (1- to 2-year-olds) may require more time to develop emotional bonds [ 40 ], a sense of closeness [ 41 ], and psychological attributions [ 10 , 32 ]. Although few studies have explored individual differences in children's interactions with robots, Baxter et al. [ 42 ] highlighted the importance of these factors. Tolksdorf et al. [ 43 ] found that shy children initially exhibited fewer positive reactions to robots than non-shy children but became more comfortable over time. Therefore, future research should consider individual differences such as personality, temperament, and familiarity with robots when examining task persistence. 5. Conclusion This study is the first to show that praise from the CommU may encourage persistence in children aged 18–24 months. We also demonstrated for the first time that children's persistence increases when they looked at the CommU. While caution is needed when interpreting whether praise from a robot serves as a social reward equivalent to human praise [ 44 ], our findings suggest that CommU, as a simplified social agent, may enhance social awareness in children aged one to two years. The results of this study highlight the potential of social robots to contribute to play and learning in early childhood beyond the specific task persistence behavior examined in this research. Declarations Acknowledgments The authors are extremely grateful to the parents who completed the survey. We also thank Ms. Chiaki Kimura for her great help. This research was supported by MEXT “Innovation Platform for Society 5.0” (Grant number: JPMXP0518071489) Author Contributions Conceptualization: Mikako Ishibashi; Yuta Shinya; Shoji Itakura; Methodology: Mikako Ishibashi; Yuta Shinya; Formal analysis and investigation: Mikako Ishibashi; Yuta Shinya; Writing - original draft preparation: Mikako Ishibashi ; Writing - review and editing: Yuta Shinya; Shoji Itakura; Funding acquisition: Shoji Itakura; Resources: Shoji Itakura; Yuichiro Yoshikawa; Hiroshi Ishiguro; Supervision: Shoji Itakura; Yuichiro Yoshikawa; Hiroshi Ishiguro Conflicts of Interest The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. Data Statement The raw data supporting the conclusions of this article will be made available by the authors, without undue reservation. 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Cognition 193:104025. https://doi.org/10.1016/j.cognition.2019.104025 Radovanovic M, Soldovieri A, Sommerville JA (2023) It takes two: Process praise linking trying and success is associated with greater infant persistence. Dev Psychol 59:1668–1675. https://doi.org/10.1037/dev0001584 Deater‐Deckard K, Petrill SA, Thompson LA, DeThorne LS (2006) A longitudinal behavioral genetic analysis of task persistence. Dev Sci 9:498–504. https://doi.org/10.1111/j.1467-7687.2006.00517.x Mokrova IL, O’Brien M, Calkins SD, Leerkes EM, Marcovitch S (2013) The role of persistence at preschool age in academic skills at kindergarten. Eur J Psychol Educ 28:1495–1503. https://doi.org/10.1111/bjdp.12358 Leonard JA, Lee Y, Schulz LE (2017) Infants make more attempts to achieve a goal when they see adults persist. Science 357:1290–1294. https://doi.org/10.1126/science.aan2317 Shinya Y, Ishibashi M (2022) Observing effortful adults enhances not perseverative but sustained attention in infants aged 12 months. Cogn Dev 64:101255. https://doi.org/10.1016/j.cogdev.2022.101255 Okumura Y, Hattori T, Fujita S, Kobayashi T (2023) A robot is watching me!: Five‐year‐old children care about their reputation after interaction with a social robot. Child Dev 94:865–873. https://doi.org/10.1111/cdev.13903 Bates, D., Maechler, M., Bolker, B., Walker, S., Christensen, R. H. B., Singmann, H., ... & Bolker, M. B. (2015). Package ‘lme4’. convergence, 12 (1), 2. Putnam SP, Sehic E, French BF, Gartstein MA, Lira Luttges B, 486 Additional Partners in the Global Temperament Project (2024) The Global Temperament Project: Parent-reported temperament in infants, toddlers, and children from 59 nations. Dev Psychol 60:916–941. https://doi.org/10.1037/dev0001732 Rothbart MK, Ahadi SA, Evans DE (2000) Temperament and personality: Origins and outcomes. J Pers Soc Psychol 78:122–135. https://doi.org/10.1037//0022-3514.78.1.122 Rothbart MK, Bates JE (2007) Temperament. In: Damon W, Lerner RM (eds) Handbook of Child Psychology. John Wiley & Sons, Chichester. https://doi.org/10.1002/9780470147658.chpsy0303 Anzalone SM, Tilmont E, Boucenna S, Xavier J, Jouen AL, Bodeau N, Maharatna K, Chetouani M, Cohen D, Chetouani M, Cohen D (2014) How children with autism spectrum disorder behave and explore the 4-dimensional (spatial 3D+ time) environment during a joint attention induction task with a robot. Res Autism Spec Disord 8:814–826. https://doi.org/10.1016/j.rasd.2014.03.002 Pennisi P, Tonacci A, Tartarisco G, Billeci L, Ruta L, Gangemi S, Pioggia G (2016) Autism and social robotics: A systematic review. Autism Res 9:165–183. https://doi.org/10.1002/aur.1527 Dubois-Sage M, Jacquet B, Jamet F, Baratgin J (2024) People with autism spectrum disorder could interact more easily with a robot than with a human: Reasons and limits. Behav Sci (Basel) 14:131. https://doi.org/10.3390/bs14020131 Ahmad MI, Mubin O, Shahid S, Orlando J (2019) Robot’s adaptive emotional feedback sustains children’s social engagement and promotes their vocabulary learning: A long-term child–robot interaction study. Adapt Behav 27:243–266). https://doi.org/10.1177/1059712319844182 Kose-Bagci H, Ferrari E, Dautenhahn K, Syrdal DS, Nehaniv CL (2009) Effects of embodiment and gestures on social interaction in drumming games with a humanoid robot. Adv Robot 23:1951–1996. https://doi.org/10.1163/016918609X12518783330360 Baxter P, Ashurst E, Read R, Kennedy J, Belpaeme T (2017) Robot education peers in a situated primary school study: Personalisation promotes child learning. PLOS One 12:e0178126. https://doi.org/10.1371/journal.pone.0178126 Tolksdorf NF, Viertel FE, Rohlfing KJ (2021) Do shy preschoolers interact differently when learning language with a social robot? An analysis of interactional behavior and word learning. Front Robot AI 8:676123. https://doi.org/10.3389/frobt.2021.676123 Dautenhahn, K. (2007). Socially intelligent robots: dimensions of human–robot interaction. Philosophical transactions of the royal society B: Biological sciences, 362 (1480), 679-704. doi:org/10.1098/rstb.2006.2004 Further reading Jung A, Ishibashi M, Shinya Y, Itakura S (2024) Relationship between maternal grit and effortful control among 18–21-month-old toddlers. Front Psychol 15:1346428. https://doi.org/10.3389/fpsyg.2024.1346428 Additional Declarations The authors declare no competing interests. Supplementary Files Appendix.docx 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. 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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-6301569","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":433608867,"identity":"669ec9cf-107b-4da4-a584-31f5f31c4cc2","order_by":0,"name":"Mikako Ishibashi","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA80lEQVRIie3RsarCMBSA4XPIWnAVHHwCoS53Ex/ESRycAo4dVI4U6uIDRBT7Cu3SuSVQF8FVsIPlgi/QxeEO9xTRzaqbYP4phPOFhACYTB8ZkgA7BqgjITm8IQS9Q3YlwWeEZwBKwnrmXQ+pHG+RcIvRKGs2Vy7hcjPp1eZMLk70kPzE6DWUfW4HWUIYRlupNN9wsTtWEmHZGoN6nzCPUklMBHqVxC2YdH1VknUq/RcINZj06cAkpLEMnhLNb7Hs8yBgkqg0liGTpPIt2/lvYf1lHV8N83wxnsrNXieni/OYlJ9yLwbQt8XrTd8ZNplMpi/pH5fSY67TkOgIAAAAAElFTkSuQmCC","orcid":"https://orcid.org/0000-0001-5430-7786","institution":"","correspondingAuthor":true,"prefix":"","firstName":"Mikako","middleName":"","lastName":"Ishibashi","suffix":""},{"id":433608868,"identity":"d9378521-4931-4910-b6d1-c821056723c4","order_by":1,"name":"Yuta Shinya","email":"","orcid":"https://orcid.org/0000-0002-5229-1554","institution":"The University of Tokyo","correspondingAuthor":false,"prefix":"","firstName":"Yuta","middleName":"","lastName":"Shinya","suffix":""},{"id":433608869,"identity":"76a439c5-8e89-4cf9-a014-b492501945ef","order_by":2,"name":"Yuichiro Yoshikawa","email":"","orcid":"https://orcid.org/0000-0002-3484-0361","institution":"Osaka University","correspondingAuthor":false,"prefix":"","firstName":"Yuichiro","middleName":"","lastName":"Yoshikawa","suffix":""},{"id":433608870,"identity":"ef2bc71e-1f9a-4ad8-9c23-ed4bde2325af","order_by":3,"name":"Hiroshi Ishiguro","email":"","orcid":"https://orcid.org/0000-0002-0805-7648","institution":"ATR Hiroshi Ishiguro Laboratories","correspondingAuthor":false,"prefix":"","firstName":"Hiroshi","middleName":"","lastName":"Ishiguro","suffix":""},{"id":433608871,"identity":"139b5805-3712-4ca6-909b-10c769d9bcb6","order_by":4,"name":"Shoji Itakura","email":"","orcid":"https://orcid.org/0000-0003-1713-2002","institution":"Ritsumeikan University","correspondingAuthor":false,"prefix":"","firstName":"Shoji","middleName":"","lastName":"Itakura","suffix":""}],"badges":[],"createdAt":"2025-03-25 08:13:58","currentVersionCode":1,"declarations":{"humanSubjects":true,"vertebrateSubjects":false,"conflictsOfInterestStatement":false,"humanSubjectEthicalGuidelines":true,"humanSubjectConsent":true,"humanSubjectClinicalTrial":false,"humanSubjectCaseReport":false,"vertebrateSubjectEthicalGuidelines":false},"doi":"10.21203/rs.3.rs-6301569/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-6301569/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":79265980,"identity":"2446d897-bddb-4a59-8332-201aff377e55","added_by":"auto","created_at":"2025-03-26 10:07:50","extension":"jpeg","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":174475,"visible":true,"origin":"","legend":"\u003cp\u003eMean time (s) of Trying for the No Praise and Praise condition per Agent\u003c/p\u003e","description":"","filename":"floatimage1.jpeg","url":"https://assets-eu.researchsquare.com/files/rs-6301569/v1/95678052edaede81282263b6.jpeg"},{"id":79265391,"identity":"8eeec8f0-63df-48d5-9528-239bd4f2fb5a","added_by":"auto","created_at":"2025-03-26 09:59:50","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":66179,"visible":true,"origin":"","legend":"\u003cp\u003eCorrelation between Trying and Look in the CommU condition (left) in the Human condition (right). Red = No Praise condition, Green = Praise condition\u003c/p\u003e","description":"","filename":"floatimage2.png","url":"https://assets-eu.researchsquare.com/files/rs-6301569/v1/bd1340f0612c96015cf03ef7.png"},{"id":79267759,"identity":"98725cba-d45d-45c9-8399-bb2a83c0abe1","added_by":"auto","created_at":"2025-03-26 10:23:57","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":929363,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-6301569/v1/52054a99-94d7-42ed-b216-252df55a8c10.pdf"},{"id":79265393,"identity":"769a3ff8-e918-4ba2-9c49-63b38dedefa4","added_by":"auto","created_at":"2025-03-26 09:59:50","extension":"docx","order_by":1,"title":"","display":"","copyAsset":false,"role":"supplement","size":13982,"visible":true,"origin":"","legend":"","description":"","filename":"Appendix.docx","url":"https://assets-eu.researchsquare.com/files/rs-6301569/v1/1b9e603d80f3c058c6658de2.docx"}],"financialInterests":"The authors declare no competing interests.","formattedTitle":"\u003cp\u003e\u003cstrong\u003eEnhancing Task Persistence in 18- to 24-Month-Old Children through Social Robot Interaction\u003c/strong\u003e\u003c/p\u003e","fulltext":[{"header":"1. Introduction","content":"\u003cp\u003eSocial robots, defined as robots that can interact socially and communicate with humans and other autonomous physical entities [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e], are being introduced into children's daily lives [\u003cspan additionalcitationids=\"CR3 CR4\" citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e], with their presence in homes and classrooms expected to increase rapidly [\u003cspan additionalcitationids=\"CR7\" citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e]. There are various types of social robots, including androids, dolls, and animal-like designs, each capable of eliciting beneficial social behaviors in children [\u003cspan additionalcitationids=\"CR10\" citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eIn particular, when robots respond appropriately to children's actions and words [\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e], behave like friends [\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e], or express emotions [\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e], they are more likely to perceive them as social beings. Kumazaki et al. [\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e] suggested that when social robots are introduced to young children, robots with small sizes and simple designs may be preferred. CommU (Vstone Co., Ltd.) is a relatively simple robot that lacks a human-like appearance but has a child-like form and is approximately 30 cm tall [\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e]. Considering the CommU's design is simple, it conveys less information than Android robots and is less likely to create social pressure, allowing users to focus more on social cues [\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eSeveral studies have demonstrated that CommUs are effective at promoting social communication. For instance, conversations with CommU facilitate self-disclosure among users [\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e]. Moreover, individuals with ASD felt more comfortable communicating with CommU than with humans [\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e], suggesting that CommU may be useful in fostering relationships and providing psychological support. Furthermore, CommU has been applied in learning support, with training via CommU improving joint attention (JA) in children, leading to enhanced performance in subsequent JA tasks with humans [\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e]. Thus, the CommU has proven an effective tool for supporting children's learning.\u003c/p\u003e \u003cp\u003eOne specific type of supporting children\u0026rsquo;s social learning that social robots can provide is praise. Shiomi et al. [\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e] examined the effects of praise received from two robots on children's learning. Praise is a fundamental social reward that motivates young children to achieve their goals and fosters their desire to learn [\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e]. Shiomi et al. [\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e] compared the duration of English learning sessions among children aged 4 to 6 under two conditions: when one robot praised them versus when two robots praised them. The results showed that when two robots praised the children, they spent significantly more time learning English than when only one robot praised them. This study suggests that praise from robots can encourage learning persistence in young children.\u003c/p\u003e \u003cp\u003eSimilar to Shiomi et al. [\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e], other studies have examined the effects of robot-administered praise [\u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e, \u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e]; however, all these studies focused on school-aged or older children. Collecting sufficient research data on robots interacting with children under four years old is challenging due to their strong resistance to robots [\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e]. Consequently, except for Tanaka et al. [\u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e25\u003c/span\u003e], few studies have explored the interactions between robots and typically developing children aged one or two years.\u003c/p\u003e \u003cp\u003eTanaka et al. [\u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e25\u003c/span\u003e] placed a robot in a nursery room for children aged 18\u0026ndash;24 months over a five-month period. The robot (QRIO) used in this study was relatively small (58 cm tall), and its facial structure was similar to that of the CommU, with cameras mounted above both eyes. The robot was programmed to provide contingent responses to the children over 45 sessions, leading to improved child\u0026ndash;robot interaction quality, including caretaking behavior and conversation, over time. These findings suggest that even children as young as 18\u0026ndash;24 months can establish social interactions with robots. However, to the best of our knowledge, no studies have empirically investigated the effects of robot-administered praise on toddlers (18\u0026ndash;24 months).\u003c/p\u003e \u003cp\u003eThe effects of praise on children aged one to two years were examined from the perspective of task persistence. Lucca et al. [\u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e26\u003c/span\u003e] conducted an experiment to investigate the impact of parental encouragement on children aged 18\u0026ndash;24 months. The results showed that children who received process-focused praise from their parents spent more time working on tasks than those who did not receive praise [\u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e26\u003c/span\u003e]. Additionally, Radovanovic et al. [\u003cspan citationid=\"CR27\" class=\"CitationRef\"\u003e27\u003c/span\u003e] found that children's (17\u0026ndash;31 months) persistence was maximized when parental praise was timed to coincide with their engagement in the task.\u003c/p\u003e \u003cp\u003eWith regard to early expressions of persistence, it should be noted that they are widely influenced by interactions with the social environment [\u003cspan citationid=\"CR28\" class=\"CitationRef\"\u003e28\u003c/span\u003e, \u003cspan citationid=\"CR29\" class=\"CitationRef\"\u003e29\u003c/span\u003e]. Recent research has shown that infants\u0026rsquo; behavioral and attentional persistence may be enhanced when infants observe persistence in others [\u003cspan citationid=\"CR30\" class=\"CitationRef\"\u003e30\u003c/span\u003e, \u003cspan citationid=\"CR31\" class=\"CitationRef\"\u003e31\u003c/span\u003e]. Therefore, the effects of praise on children's persistence may also depend on their awareness of others as social beings. For example, Okumura et al. [\u003cspan citationid=\"CR32\" class=\"CitationRef\"\u003e32\u003c/span\u003e] found that five-year-olds who were observed by a social interactive robot shared more stickers than those interacting with an attentional but non-interactive or stationary robot, suggesting that five-year-olds adjust their own behaviour based on whether or not the other is a social being. However, it remains unclear whether social awareness of the robot presence enhances young children's persistence.\u003c/p\u003e \u003cp\u003eIn this study, we experimentally investigated whether the praise of the social robot CommU could enhance the persistence of young children aged18\u0026ndash;24 months in the same way as human praise. As it has been suggested that young children preferred the small sized robot [\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e], we considered that CommU to be appropriate for 18\u0026ndash;24 months in this study. Also, Kumazaki et al. [\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e] pointed out that CommU has a high degree of eye movement flexibility, indicating that it easily captures users' attention from children. Given that parental encouragement has been shown to enhance task persistence in children aged 18 to 24 months [\u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e26\u003c/span\u003e] and that young children perceive robots as social beings [\u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e25\u003c/span\u003e], we hypothesized that the praise from CommU would contribute to children's task persistence in a manner similar to human praise. Furthermore, we investigated whether looking toward CommU would be associated with the persistence of young children, considering social awareness of the robot would adjust their social behavior (e.g., [\u003cspan citationid=\"CR32\" class=\"CitationRef\"\u003e32\u003c/span\u003e]).\u003c/p\u003e"},{"header":"2. Method","content":"\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e \u003ch2\u003e2.1. Participants\u003c/h2\u003e \u003cp\u003eFollowing a previous study [\u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e26\u003c/span\u003e], we recruited children aged 18\u0026ndash;24 months. 86 18\u0026ndash;24 months participated in this study. Fourteen out of 86 children were excluded for the following reasons: (1) children could not perform the task itself because of fear of the CommU (\u003cem\u003en\u003c/em\u003e\u0026thinsp;=\u0026thinsp;2); (2) children were not motivated to participate or remained clinging to their mother for 2 min (\u003cem\u003en\u003c/em\u003e\u0026thinsp;=\u0026thinsp;7); and (3) experimental error in the procedure (\u003cem\u003en\u003c/em\u003e\u0026thinsp;=\u0026thinsp;5). The sample size estimation required 32 participants per condition and the study was terminated when 32 children participated. However, 8 children were excluded during the coding because they did not engage in the entire persistent task. The final number of participants used in the analysis was 58 (30 girls; mean age\u0026thinsp;=\u0026thinsp;20.79 months, \u003cem\u003eSD\u003c/em\u003e\u0026thinsp;=\u0026thinsp;2.05). The CommU condition included 30 participants (mean age\u0026thinsp;=\u0026thinsp;20.87 months, \u003cem\u003eSD\u003c/em\u003e\u0026thinsp;=\u0026thinsp;2.36) and the Human condition included 28 participants (mean age\u0026thinsp;=\u0026thinsp;20.71 months, \u003cem\u003eSD\u003c/em\u003e\u0026thinsp;=\u0026thinsp;1.70).\u003c/p\u003e \u003cp\u003eThis study was approved by the ethical committee of the Doshisha University(number: 20029).\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec4\" class=\"Section2\"\u003e \u003ch2\u003e2.2. Stimuli\u003c/h2\u003e \u003cp\u003eA toy with stacked gears was used in a previous study [\u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e26\u003c/span\u003e]. This toy comprised a bar with a base and six disks that could be stacked on top. A sponge was glued to the center of the disk or a rubber band was glued to the disk to prevent stacking.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec5\" class=\"Section2\"\u003e \u003ch2\u003e2.3. Procedure\u003c/h2\u003e \u003cdiv id=\"Sec6\" class=\"Section3\"\u003e \u003ch2\u003e2.3.1. Experimental Setup\u003c/h2\u003e \u003cp\u003eIn the CommU condition, the child, his/her mother, an experimental assistant, and the CommU were in an experimental room.\u003c/p\u003e \u003cp\u003eFirst, before the task was conducted, we allowed sufficient time (approximately 10\u0026ndash;20 min) for interaction with the CommU for the children to relax. None of the children who participated in the experiment had previously interacted with the CommU, and the experimental assistant provided support to facilitate the interaction among the CommU, mother, and child.\u003c/p\u003e \u003cp\u003eAfter confirming that the child was familiar with the CommU (e.g., talking to, laughter, or touching the CommU), the experimental assistant prepared the tools used in the persistent task.\u003c/p\u003e \u003cp\u003eIn the Human condition, the child and her mother were escorted by the experimental assistant into the experimental room.\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv id=\"Sec7\" class=\"Section2\"\u003e \u003ch2\u003e2.4. Persistent task\u003c/h2\u003e \u003cp\u003eWe set two conditions under which the agent praised or did not praise the child. The with/without praise condition was a within-participant design, and the order of the conditions was randomized between the participants. The agent, CommU/Human, was between the participant designs.\u003c/p\u003e \u003cdiv id=\"Sec8\" class=\"Section3\"\u003e \u003ch2\u003e2.4.1. Demonstration of the task\u003c/h2\u003e \u003cp\u003eFirst, the experimenter said, \" x-chan [child\u0026rsquo;s name], look\", to draw the child's attention, and then demonstrated how to remove the sponge from the disk and insert the disk into the bar. The experimenter then handed another disk to the child and said, \"Here you go, [the child\u0026rsquo;s name]\u0026rdquo;. After the child received the disk, the time was measured for 2 min and the child's behavior was observed. To play with the toy, the child needed to insert the disk in the center into the stick; however, the disk glued to sponges or rubber bands could not be inserted. The order of the sponges and rubber bands was presented randomly.\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv id=\"Sec9\" class=\"Section2\"\u003e \u003ch2\u003e2.5. CommU condition\u003c/h2\u003e \u003cdiv id=\"Sec10\" class=\"Section3\"\u003e \u003ch2\u003e2.5.1. Praise condition\u003c/h2\u003e \u003cp\u003eThe CommU praised the child every 10 s after the disk was handed to him/her. The timing of praise was fixed at every 10 s for 2 min. Praise was given in the following order: \"[child\u0026rsquo;s name], you are doing well\", \"[child\u0026rsquo;s name], you are looking good\", and \"[child\u0026rsquo;s name], you are doing well\". In Shiomi's study [\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e], a human operator was incorporated into the system to control the timing of the robot's actions because children behaved unexpectedly. As in Shiomi [\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e], the timing of the praise was fixed (praising once every 10 s). We selected sentences that were not unnatural, even when the child was attempting to perform an unattainable task. The operator remotely controlled the CommU and moved the CommU\u0026rsquo;s face and body appropriately in response to the child\u0026rsquo;s movements. After 2 min, the experimenter again drew the child's attention and handed the child a disk that could be inserted into the stick to reduce frustration.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec11\" class=\"Section3\"\u003e \u003ch2\u003e2.5.2. No Praise condition\u003c/h2\u003e \u003cp\u003eThe disks and sticks with bases used in the praise condition were removed, and new disks and sticks with bases were placed on the floor. The disks had a rubber band attached to them, and the experimenter demonstrated by showing the removal of the rubber band attached to the disk. The measurements began after the child was provided with a disk. As in the praise condition, the face and body moved in accordance with the child's movements.\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv id=\"Sec12\" class=\"Section2\"\u003e \u003ch2\u003e2.6. Human condition\u003c/h2\u003e \u003cdiv id=\"Sec13\" class=\"Section3\"\u003e \u003ch2\u003e2.6.1. Praise condition\u003c/h2\u003e \u003cp\u003eA human praised the child every 10 s after handling the disk. The lines and order of praise were the same as in the CommU condition. After 2 min, the experimenter again drew the child\u0026rsquo;s attention and handed them a disk they could insert into the stick to reduce frustration.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec14\" class=\"Section3\"\u003e \u003ch2\u003e2.6.2. No Praise condition\u003c/h2\u003e \u003cp\u003eThe disks and sticks used in the praise condition were removed, and new disks and sticks with bases were placed. The disks had a rubber band attached to them, and the experimenter demonstrated by showing the removal of the rubber band attached to the disks. The measurements began after the disks were handed over to the children. As in the praise condition, the face and body moved according to the child's movements.\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv id=\"Sec15\" class=\"Section2\"\u003e \u003ch2\u003e2.7. Coding schema\u003c/h2\u003e \u003cdiv id=\"Sec16\" class=\"Section3\"\u003e \u003ch2\u003e2.7.1. Trying\u003c/h2\u003e \u003cp\u003eChildren\u0026rsquo;s persistence was measured as described by Lucca et al [\u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e26\u003c/span\u003e]. We named it \u0026ldquo;Trying,\u0026rdquo; and the following two behaviors were measured:\u003c/p\u003e \u003cp\u003e(1) Inserting disk into stick: Trying was coded when the disk was placed at the tip of the stick. The start time was when the child was placed on the disk at the tip of the stick, and the end time was when the disk left the tip of the stick.\u003c/p\u003e \u003cp\u003e(2) Removal of sponge/rubber band from disks: The time at which each child attempted to remove the sponge or rubber band glued to a disk was recorded. The start time was when the child was trying to put his/her finger on the sponge or remove the rubber band, and the end time was when the child's finger left the disk.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec17\" class=\"Section3\"\u003e \u003ch2\u003e2.7.2. Look\u003c/h2\u003e \u003cp\u003eWe counted the duration of the children\u0026rsquo;s looking time in the CommU/Human condition. Looking was counted when the child looked at the CommU (in the CommU condition) or human (in the Human condition) for at least 1 s.\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e"},{"header":"3. Results","content":"\u003cp\u003eDescriptive statistics are shown for each agent with and without praise (Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e). We also show the mean time spent trying between the no praise and praise conditions for each agent (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e).\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab1\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eMean and standard deviation of Trying and Look with/without praise per Agent.\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"4\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAgent\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eCondition\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eMean of Trying (\u003cem\u003eSD\u003c/em\u003e)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eMean of Look (\u003cem\u003eSD\u003c/em\u003e)\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCommU\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eNo praise\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e26.3 (27.31)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e12.01 (11.97)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCommU\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003ePraise\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e32.22 (27.48)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e11.86 (10.1)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eHuman\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eNo praise\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e21.04 (26.42)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e7.84 (7.35)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eHuman\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003ePraise\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e24.91 (23.28)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e8.00 (8.7)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eWe measured looking during the task and examined the relationship between the length of looking and trying using correlation analysis. In the CommU condition, correlation analysis revealed no significant correlation between trying and looking in the praise condition (\u003cem\u003er\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.10, \u003cem\u003ep\u003c/em\u003e\u0026thinsp;=\u0026thinsp;.59) and in the no praise condition (\u003cem\u003er\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.35, \u003cem\u003ep\u003c/em\u003e\u0026thinsp;=\u0026thinsp;.06). In the Human condition, the correlation analysis revealed a significant correlation between trying and Look in the praise condition ( \u003cem\u003er\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.58, \u003cem\u003ep\u003c/em\u003e\u0026thinsp;=\u0026thinsp;.00) and in the no praise condition (\u003cem\u003er\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.71, \u003cem\u003ep\u003c/em\u003e\u0026thinsp;=\u0026thinsp;.00).\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cdiv id=\"Sec19\" class=\"Section2\"\u003e \u003ch2\u003e3.1 Analysis\u003c/h2\u003e \u003cp\u003eWe conducted linear mixed-effects models (LMMs) using the lmer function from the lme4 package in R [\u003cspan citationid=\"CR33\" class=\"CitationRef\"\u003e33\u003c/span\u003e] to examine the effects of age, sex, Condition (praise/no praise), Look, and Agent (CommU/Human) on Trying behavior. We included the participants as random intercepts to account for individual differences. Age and Look variables were standardized using z-scores. Model 1 was explained as a baseline model to assess the effects of standardized age and sex on trying behaviors. A random intercept for the participants (ID) was included as an individual difference. Model 2 was extended to Model 1 by adding the condition (praise/no praise), Standardized Look, and Agent (CommU/Human) as fixed effects. Model 3 further explained the interaction to examine the effects of Condition and Look on the agent\u0026rsquo;s trying behavior. Each model is described in detail in the Appendix.\u003c/p\u003e \u003cp\u003eThe LMM results are shown in Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e. In Model 1, standardized age was positively associated with trying (\u003cem\u003eB\u003c/em\u003e\u0026thinsp;=\u0026thinsp;8.06, \u003cem\u003eSE\u003c/em\u003e\u0026thinsp;=\u0026thinsp;3.11, \u003cem\u003et\u003c/em\u003e\u0026thinsp;=\u0026thinsp;2.59, \u003cem\u003ep\u003c/em\u003e\u0026thinsp;=\u0026thinsp;.01), while sex did not show a significant effect (\u003cem\u003eB\u003c/em\u003e= -7.18, \u003cem\u003eSE\u003c/em\u003e\u0026thinsp;=\u0026thinsp;6.22, \u003cem\u003et\u003c/em\u003e = -1.16, \u003cem\u003ep\u003c/em\u003e\u0026thinsp;=\u0026thinsp;.25).\u003c/p\u003e \u003cp\u003eIn Model 2, standardized age remained significant (\u003cem\u003eB\u003c/em\u003e\u0026thinsp;=\u0026thinsp;7.15, \u003cem\u003eSE\u003c/em\u003e\u0026thinsp;=\u0026thinsp;2.83, \u003cem\u003et\u003c/em\u003e\u0026thinsp;=\u0026thinsp;2.53, \u003cem\u003ep\u003c/em\u003e\u0026thinsp;=\u0026thinsp;.01). In addition, condition and looking behavior were significant predictors of trying (Condition: \u003cem\u003eB\u003c/em\u003e\u0026thinsp;=\u0026thinsp;5.09, \u003cem\u003eSE\u003c/em\u003e\u0026thinsp;=\u0026thinsp;2.45, \u003cem\u003et\u003c/em\u003e\u0026thinsp;=\u0026thinsp;2.08, \u003cem\u003ep\u003c/em\u003e\u0026thinsp;=\u0026thinsp;.04, Look: \u003cem\u003eB\u003c/em\u003e\u0026thinsp;=\u0026thinsp;10.61, \u003cem\u003eSE\u003c/em\u003e\u0026thinsp;=\u0026thinsp;2.93, \u003cem\u003et\u003c/em\u003e\u0026thinsp;=\u0026thinsp;3.62, \u003cem\u003ep\u003c/em\u003e\u0026thinsp;=\u0026thinsp;.00).\u003c/p\u003e \u003cp\u003eModel 3 showed that standardized age, condition, and looking behavior remained significant predictors of trying (Standardized Age: \u003cem\u003eB\u003c/em\u003e\u0026thinsp;=\u0026thinsp;6.58, \u003cem\u003eSE\u003c/em\u003e\u0026thinsp;=\u0026thinsp;2.82, \u003cem\u003et\u003c/em\u003e\u0026thinsp;=\u0026thinsp;2.34, \u003cem\u003ep\u003c/em\u003e\u0026thinsp;=\u0026thinsp;.02; Look: \u003cem\u003eB\u003c/em\u003e\u0026thinsp;=\u0026thinsp;7.29, \u003cem\u003eSE\u003c/em\u003e\u0026thinsp;=\u0026thinsp;3.59, \u003cem\u003et\u003c/em\u003e\u0026thinsp;=\u0026thinsp;2.03, \u003cem\u003ep\u003c/em\u003e\u0026thinsp;=\u0026thinsp;.05). The effect of the condition was marginally significant (\u003cem\u003eB\u003c/em\u003e\u0026thinsp;=\u0026thinsp;6.24, \u003cem\u003eSE\u003c/em\u003e\u0026thinsp;=\u0026thinsp;3.43, \u003cem\u003et\u003c/em\u003e\u0026thinsp;=\u0026thinsp;1.82, \u003cem\u003ep\u003c/em\u003e\u0026thinsp;=\u0026thinsp;.07). There was no significant interaction effect between the Agent and Condition, and between Agent and Look. All the interactions between the Condition and Agent (\u003cem\u003ep\u003c/em\u003e\u0026thinsp;=\u0026thinsp;.63) and between the Look and the Agent (\u003cem\u003ep\u003c/em\u003e\u0026thinsp;=\u0026thinsp;.13) were not significant, and the main effect of the condition, which was significant in Model 2, became a significant trend (\u003cem\u003ep\u003c/em\u003e\u0026thinsp;=\u0026thinsp;.07).\u003c/p\u003e \u003cp\u003eThe likelihood ratio test indicated that Model 2 exhibited significantly improved fit compared to Model 1 (χ\u0026sup2;(3)\u0026thinsp;=\u0026thinsp;17.79, \u003cem\u003ep\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;.001). However, no significant effect between Model 2 and Model 3 (χ\u0026sup2;(2)\u0026thinsp;=\u0026thinsp;2.87, \u003cem\u003ep\u003c/em\u003e\u0026thinsp;=\u0026thinsp;.24), suggesting that the effect of interaction of Model 3 did not improve significantly. In addition, the models showed the lowest AIC (\u003cem\u003eAIC\u003c/em\u003e\u0026thinsp;=\u0026thinsp;1034), indicating that Model 2 was the best-fit model among other models.\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab2\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 2\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eResults of comparison of LMM models\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"12\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c7\" colnum=\"7\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c8\" colnum=\"8\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c9\" colnum=\"9\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c10\" colnum=\"10\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c11\" colnum=\"11\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c12\" colnum=\"12\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colspan=\"4\" nameend=\"c5\" namest=\"c2\"\u003e \u003cp\u003eModel 1\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"4\" nameend=\"c9\" namest=\"c6\"\u003e \u003cp\u003eModel 2\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"3\" nameend=\"c12\" namest=\"c10\"\u003e \u003cp\u003eModel 3\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cem\u003ePredictors\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u003cem\u003eB\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e95%CI\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u003cem\u003eP\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c6\" namest=\"c5\"\u003e \u003cp\u003e\u003cem\u003eB\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e95%CI\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e\u003cem\u003eP\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c10\" namest=\"c9\"\u003e \u003cp\u003e\u003cem\u003eB\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e95%CI\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e \u003cp\u003e\u003cem\u003eP\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e(Intercept)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e29.78\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e21.24\u0026ndash;38.31\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;0.001\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c6\" namest=\"c5\"\u003e \u003cp\u003e26.08\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e16.45\u0026ndash;35.72\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;0.001\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c10\" namest=\"c9\"\u003e \u003cp\u003e26.01\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e16.18\u0026ndash;35.84\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e \u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;0.001\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eStandardized Age\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e8.06\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1.90\u0026ndash;14.22\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u003cb\u003e0.011\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c6\" namest=\"c5\"\u003e \u003cp\u003e7.15\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e1.54\u0026ndash;12.76\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e\u003cb\u003e0.013\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c10\" namest=\"c9\"\u003e \u003cp\u003e6.58\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e0.99\u0026ndash;12.16\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e \u003cp\u003e\u003cb\u003e0.021\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSex [m]\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e-7.18\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e\u0026minus;\u0026thinsp;19.46\u0026ndash;5.10\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.249\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c6\" namest=\"c5\"\u003e \u003cp\u003e-4.17\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e-15.45\u0026ndash;7.10\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e0.465\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c10\" namest=\"c9\"\u003e \u003cp\u003e-3.59\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e\u0026minus;\u0026thinsp;14.74\u0026ndash;7.57\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e \u003cp\u003e0.525\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCondition [Praise]\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c6\" namest=\"c5\"\u003e \u003cp\u003e5.09\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.23\u0026ndash;9.95\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e\u003cb\u003e0.040\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c10\" namest=\"c9\"\u003e \u003cp\u003e6.24\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e-0.57\u0026ndash;13.04\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e \u003cp\u003e0.072\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eStandardized Look\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c6\" namest=\"c5\"\u003e \u003cp\u003e10.61\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e4.80\u0026ndash;16.41\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;0.001\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c10\" namest=\"c9\"\u003e \u003cp\u003e7.29\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e0.18\u0026ndash;14.41\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e \u003cp\u003e\u003cb\u003e0.045\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAgent [human]\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c6\" namest=\"c5\"\u003e \u003cp\u003e-0.63\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e-12.10\u0026ndash;10.85\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e0.914\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c10\" namest=\"c9\"\u003e \u003cp\u003e1.16\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e-11.21\u0026ndash;13.52\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e \u003cp\u003e0.853\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCondition [Praise] x\u003c/p\u003e \u003cp\u003eAgent [human]\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c6\" namest=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c10\" namest=\"c9\"\u003e \u003cp\u003e-2.37\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e\u0026minus;\u0026thinsp;12.17\u0026ndash;7.42\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e \u003cp\u003e0.632\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAgent [human] x\u003c/p\u003e \u003cp\u003eStandardized Look\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c6\" namest=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c10\" namest=\"c9\"\u003e \u003cp\u003e9.34\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e-2.57\u0026ndash;21.26\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e \u003cp\u003e0.123\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eObservations\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"3\" nameend=\"c4\" namest=\"c2\"\u003e \u003cp\u003e116\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"4\" nameend=\"c8\" namest=\"c5\"\u003e \u003cp\u003e116\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"4\" nameend=\"c12\" namest=\"c9\"\u003e \u003cp\u003e116\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMarginal R\u003csup\u003e2\u003c/sup\u003e / Conditional R\u003csup\u003e2\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"3\" nameend=\"c4\" namest=\"c2\"\u003e \u003cp\u003e0.108 / 0.746\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"4\" nameend=\"c8\" namest=\"c5\"\u003e \u003cp\u003e0.264 / 0.764\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"4\" nameend=\"c12\" namest=\"c9\"\u003e \u003cp\u003e0.287 / 0.764\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAIC\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"3\" nameend=\"c4\" namest=\"c2\"\u003e \u003cp\u003e1046\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"4\" nameend=\"c8\" namest=\"c5\"\u003e \u003cp\u003e1034\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"4\" nameend=\"c12\" namest=\"c9\"\u003e \u003cp\u003e1035\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003c/div\u003e"},{"header":"4. Discussion","content":"\u003cp\u003eThe purpose of this study was to empirically verify whether children 18\u0026ndash;24 months would increase their persistence in task-related behavior when praised by the social robot CommU, in the same way as when praised by a human. We examined the effects of condition (praise/no praise), agent (CommU/human), and gaze duration (children\u0026rsquo;s looking time at the agent) as predictors of children's persistence in their tasks. In the LMM model, we found that age, condition, and gaze duration were significant predictors of persistence. Specifically, we observed that persistence increased with age and was enhanced by both praise and longer gaze duration directed at the agent. Furthermore, the duration of persistence was longer when the child received praise compared to when they did not. Neither the agent-condition interaction nor the gaze-condition interaction was significant, suggesting that the effects of praise and gaze behavior independently influence children's task persistence.\u003c/p\u003e \u003cp\u003eOur results indicate that the praise of CommU could enhance task persistence of children aged 18\u0026ndash;24 months. This is consistent with previous research [\u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e26\u003c/span\u003e], which found that young children who received parental praise persisted in their tasks for longer. It also aligns with Shiomi et al. [\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e], who demonstrated that children aged 5 to 6 years spent more time working on a task when encouraged by social robots. Interestingly, our study revealed that praise from CommU sustained children's persistent behavior compared to a situation without praise. This suggests that even children as young as 18\u0026ndash;24 months may perceive CommU as a social being and respond to its social signals.\u003c/p\u003e \u003cp\u003eIn addition, regardless of whether CommU provided praise, children were drawn to the robot, leading them to look at it. Okumura et al. [\u003cspan citationid=\"CR32\" class=\"CitationRef\"\u003e32\u003c/span\u003e] found that 5-year-olds engaged in strategic reputation management by sharing more stickers when observed by a social robot compared to a non-interactive robot. This suggests that presence of robot elicit social awareness, influencing children\u0026rsquo;s social behavior.\u003c/p\u003e \u003cp\u003eSimilarly, Kumazaki et al. [\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e] noted that CommU\u0026rsquo;s high degree of eye movement freedom naturally draws user attention. Anzalone et al. [\u003cspan citationid=\"CR37\" class=\"CitationRef\"\u003e37\u003c/span\u003e] used the Nao robot\u0026mdash;a design relatively similar to CommU\u0026mdash;to train children with ASD and found that JA scores in ASD children significantly decreased when using Nao. Since Nao's eyes are smaller than CommU\u0026rsquo;s, children with ASD may have focused on non-eye-related features of Nao [\u003cspan citationid=\"CR38\" class=\"CitationRef\"\u003e38\u003c/span\u003e]. Considering these studies, it is possible that CommU's eye features increased children's social awareness, contributing to their engagement in the task.\u003c/p\u003e \u003cp\u003eA significant age effect was also observed, consistent with Radovanovic et al. [\u003cspan citationid=\"CR27\" class=\"CitationRef\"\u003e27\u003c/span\u003e], who demonstrated a linear relationship between age and engagement in a task among children aged 17 to 31 months. Previous studies suggest that as children aged one to two years grow older, they develop greater effortful control [\u003cspan additionalcitationids=\"CR35\" citationid=\"CR34\" class=\"CitationRef\"\u003e34\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR36\" class=\"CitationRef\"\u003e36\u003c/span\u003e]. Therefore, task persistence could be assumed to be related to age in children of this age group.\u003c/p\u003e \u003cp\u003ePrevious studies suggested that young children prefer small and simply designed robots [\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e]. Additionally, children aged 1\u0026ndash;2 years, with fewer preconceptions about robots, may engage in more fundamental social interactions that do not rely on advanced conversation [\u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e25\u003c/span\u003e]. Tanaka et al. [\u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e25\u003c/span\u003e] used a small, simple-faced robot (QRIO) to investigate qualitative changes in interactions with children aged 18\u0026ndash;24 months over four months. They found that robots with simpler appearances allowed children to focus more on social cues because processing excessive visual information can be challenging at this age [\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e]. Similarly, in the present study, the CommU\u0026rsquo;s simple design may have allowed children to focus on social cues such as praise and gaze.\u003c/p\u003e \u003cp\u003eCommunication with robots, less complex than with humans, is processed at an \"intermediate difficulty\" level, making robot interactions more accessible to young children [\u003cspan citationid=\"CR39\" class=\"CitationRef\"\u003e39\u003c/span\u003e]. To further investigate these considerations, future research should examine the persistence of children aged18\u0026ndash;24 months using robots other than the CommU.\u003c/p\u003e \u003cp\u003eOne limitation of this study is that we could not conclusively determine whether the social reward of praise from CommU directly increased children's persistence. Lucca et al. [\u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e26\u003c/span\u003e] argued that process-oriented praise teaches children the importance of their efforts. However, whether the effect observed in our study was due to process-oriented vocalizations or simply the presence of vocal praise remains unclear. Future research should include control conditions in which the CommU provides meaningless utterances during tasks to isolate the effects of praise as a social reward.\u003c/p\u003e \u003cp\u003eAdditionally, as in previous studies, predicting young children's responses was difficult; therefore, we did not implement contingent responses [\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e]. In this study, praise was not provided contingently to avoid cases in which children assigned to the praise condition did not engage with the disc and, therefore, would not receive praise. Prior research suggests that praise timing matters; praise given during a behavior is more effective in increasing persistence than praise given after [\u003cspan citationid=\"CR27\" class=\"CitationRef\"\u003e27\u003c/span\u003e]. Future studies could compare a randomly moving robot with one that provides contingent praise based on children's responses.\u003c/p\u003e \u003cp\u003eMoreover, in this study, the experiments began only after confirming that the children had become familiar with CommU (e.g., a child speaking CommU). However, previous research suggests that young children (1- to 2-year-olds) may require more time to develop emotional bonds [\u003cspan citationid=\"CR40\" class=\"CitationRef\"\u003e40\u003c/span\u003e], a sense of closeness [\u003cspan citationid=\"CR41\" class=\"CitationRef\"\u003e41\u003c/span\u003e], and psychological attributions [\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e, \u003cspan citationid=\"CR32\" class=\"CitationRef\"\u003e32\u003c/span\u003e]. Although few studies have explored individual differences in children's interactions with robots, Baxter et al. [\u003cspan citationid=\"CR42\" class=\"CitationRef\"\u003e42\u003c/span\u003e] highlighted the importance of these factors. Tolksdorf et al. [\u003cspan citationid=\"CR43\" class=\"CitationRef\"\u003e43\u003c/span\u003e] found that shy children initially exhibited fewer positive reactions to robots than non-shy children but became more comfortable over time. Therefore, future research should consider individual differences such as personality, temperament, and familiarity with robots when examining task persistence.\u003c/p\u003e"},{"header":"5. Conclusion","content":"\u003cp\u003eThis study is the first to show that praise from the CommU may encourage persistence in children aged 18\u0026ndash;24 months. We also demonstrated for the first time that children's persistence increases when they looked at the CommU. While caution is needed when interpreting whether praise from a robot serves as a social reward equivalent to human praise [\u003cspan citationid=\"CR44\" class=\"CitationRef\"\u003e44\u003c/span\u003e], our findings suggest that CommU, as a simplified social agent, may enhance social awareness in children aged one to two years. The results of this study highlight the potential of social robots to contribute to play and learning in early childhood beyond the specific task persistence behavior examined in this research.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eAcknowledgments\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors are extremely grateful to the parents who completed the survey. We also thank Ms. Chiaki Kimura for her great help.\u0026nbsp;This research was supported by MEXT \u0026ldquo;Innovation Platform for Society 5.0\u0026rdquo; (Grant number: JPMXP0518071489)\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003cstrong\u003eAuthor Contributions\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eConceptualization: Mikako Ishibashi; Yuta Shinya; Shoji Itakura; Methodology: Mikako Ishibashi; Yuta Shinya; Formal analysis and investigation: Mikako Ishibashi; Yuta Shinya; Writing - original draft preparation: Mikako Ishibashi ; Writing - review and editing: Yuta Shinya; Shoji Itakura; Funding acquisition: Shoji Itakura; Resources: Shoji Itakura; Yuichiro Yoshikawa; Hiroshi Ishiguro; Supervision: Shoji Itakura; Yuichiro Yoshikawa; Hiroshi Ishiguro\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConflicts of Interest\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eData Statement \u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe raw data supporting the conclusions of this article will be made available by the authors, without undue reservation.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eFong T, Nourbakhsh I, Dautenhahn K (2003) A survey of socially interactive robots. 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PLOS One 12:e0178126. https://doi.org/10.1371/journal.pone.0178126\u003c/li\u003e\n\u003cli\u003eTolksdorf NF, Viertel FE, Rohlfing KJ (2021) Do shy preschoolers interact differently when learning language with a social robot? An analysis of interactional behavior and word learning. Front Robot AI 8:676123. https://doi.org/10.3389/frobt.2021.676123\u003c/li\u003e\n\u003cli\u003eDautenhahn, K. (2007). Socially intelligent robots: dimensions of human\u0026ndash;robot interaction. Philosophical transactions of the royal society B: \u003cem\u003eBiological sciences, 362\u003c/em\u003e(1480), 679-704. doi:org/10.1098/rstb.2006.2004\u003c/li\u003e\n\u003c/ol\u003e\u003cp\u003e\u003cstrong\u003eFurther reading\u003c/strong\u003e\u003c/p\u003e\n\u003col start=\"45\"\u003e\n \u003cli\u003eJung A, Ishibashi M, Shinya Y, Itakura S (2024) Relationship between maternal grit and effortful control among 18\u0026ndash;21-month-old toddlers. Front Psychol 15:1346428. https://doi.org/10.3389/fpsyg.2024.1346428\u003c/li\u003e\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":true,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"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},"keywords":"CommU robot, Toddlers (18 to 24 months), persistence, praise effect, look","lastPublishedDoi":"10.21203/rs.3.rs-6301569/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-6301569/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eSocial robots are increasingly integrated into children's daily lives, shaping their social interactions and learning behaviors. However, no study has empirically investigated the effect of robot-administered praise on children younger than 4 years old. To address this gap, the present study focuses on social robot CommU, a simple child-shaped robot that is approximately 30 cm tall, which may exert less social pressure and help children attend to social cues more easily. We examined whether praise from the CommU enhances task persistence in children aged 18 to 24 months, similar to human praise. The results showed that children persisted longer when they were praised by the agent, regardless of the agent type (CommU vs. human). Their persistence was also positively associated with the amount of time they spent looking at the agent. Notably, most of the children exhibited attention to the CommU while engaged in the task, suggesting their heightened social awareness. These findings provide the first empirical evidence that social robot interaction can enhance task persistence in children aged 18 to 24 months, highlighting the potential role of social robots in early childhood learning.\u003c/p\u003e","manuscriptTitle":"Enhancing Task Persistence in 18- to 24-Month-Old Children through Social Robot Interaction","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-03-26 09:59:45","doi":"10.21203/rs.3.rs-6301569/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":"6311f394-0f99-4c92-b011-42e6f2c61774","owner":[],"postedDate":"March 26th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[{"id":46169386,"name":"Robotics"},{"id":46169387,"name":"Psychology"}],"tags":[],"updatedAt":"2025-03-26T09:59:45+00:00","versionOfRecord":[],"versionCreatedAt":"2025-03-26 09:59:45","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-6301569","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-6301569","identity":"rs-6301569","version":["v1"]},"buildId":"XKTyCvWXoU3ODBz1xrDgd","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}