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Front. Robot. AI | doi: 10.3389/frobt.2021.599755

Smiles as a Signal of Prosocial Behaviors Toward the Robot in the Therapeutic Setting for Children with Autism Spectrum Disorder Provisionally accepted The final, formatted version of the article will be published soon. Notify me

  • 1University of Tsukuba, Japan
  • 2Nippon Sport Science University, Japan

We explored how robot-assisted therapy based on smile analysis can facilitate the prosocial behaviors of children with Autism Spectrum Disorder. Prosocial behaviors, which are actions for benefiting others, are required to belong to society and increase the quality of life. As smiling is a candidate for predicting prosocial behaviors in robot-assisted therapy, we measured smiles by annotating behaviors which were recorded with video cameras and by classifying facial muscle activities which were recorded with a wearable device. While interacting with a robot, the participants experienced two situations where participants' prosocial behaviors are expected, which were supporting the robot to walk and helping the robot from falling down. We first explored the overall smiles at specific timings and prosocial behaviors. Then, we explored the smiles triggered by a robot and behavior changes before engaging in prosocial behaviors. The results show that the specific timing of smiles and prosocial behaviors increased in the second session of children with Autism Spectrum Disorder. In addition, a smile was followed by a series of behaviors before prosocial behavior. With a proposed Bayesian model, smiling or heading predicted prosocial behaviors with higher accuracy compared to other variables. Particularly, voluntary prosocial behaviors were observed after smiling. These findings imply that smiles might be a signal of prosocial behaviors. Therefore, we suggest the probabilistic model for predicting prosocial behaviors based on analysis of smiles. It could be applied to personalized robot-assisted therapy by controlling a robot’s movements to arouse smiles and increase the probability that a child with Autism Spectrum Disorder will engage in prosocial behaviors.

Keywords: smile, Prosocial Behavior, robot-assisted therapy, nao, Bayesian model, electromyogram

Received: 28 Aug 2020; Accepted: 08 Mar 2021.

Copyright: © 2021 Kim, Hirokawa, Matsuda, Funahashi and Suzuki. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.

* Correspondence: Ms. SunKyoung Kim, University of Tsukuba, Tsukuba, Japan,