ORIGINAL RESEARCH article
Front. Psychol.
Sec. Consciousness Research
Volume 16 - 2025 | doi: 10.3389/fpsyg.2025.1666002
Optimizing the mirror illusion during mirror therapy: Evidence from unimpaired individuals
Provisionally accepted- 1University of Birmingham School of Sport Exercise and Rehabilitation Sciences, Birmingham, United Kingdom
- 2Department of Mechanical engineering, University of Birmingham School of Engineering, Birmingham, United Kingdom
Select one of your emails
You have multiple emails registered with Frontiers:
Notify me on publication
Please enter your email address:
If you already have an account, please login
You don't have a Frontiers account ? You can register here
Mirror therapy has demonstrated functional benefits for patients recovering from hemiparetic stroke, with its effectiveness primarily attributed to the induction of a compelling visual illusion that engages sensorimotor networks. Although previous research has identified various intervention parameters influencing therapeutic outcomes, a comprehensive understanding of their effects on the illusory experience remains limited. This study investigated how four critical parameters—mirror size (large vs. small), object manipulation (present vs. absent), task complexity (simple vs. complex), and movement execution (unilateral vs. bilateral)—modulate the believability of the mirror illusion in neurologically unimpaired individuals. Forty healthy participants performed movements under 16 different combinations of these parameters while receiving mirror visual feedback and rated the believability of the reflected hand on an 11-point Likert scale. Repeated-measures ANOVA revealed that a large mirror consistently enhanced the illusory experience compared to a small mirror. Although bimanual movements generally resulted in higher believability ratings than unimanual movements, this advantage diminished when complex object manipulation tasks were introduced. These findings suggest that the congruency of multisensory information—between visual, proprioceptive, and motor signals—is critical for maximising the strength of the illusory experience. By identifying the optimal conditions for enhancing the mirror illusion in healthy individuals, this study establishes a foundational framework for adapting and refining mirror therapy protocols in clinical populations.
Keywords: mirror therapy, Upper Extremity, crossmodal illusions, multisensory, embodiment, body representation, Stroke
Received: 14 Jul 2025; Accepted: 15 Oct 2025.
Copyright: © 2025 Kim, Challis, Koo, Leung, Lo, Yeo and Punt. 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) or licensor 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: Jin Min Kim, j.m.kim@bham.ac.uk
Disclaimer: All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers. Any product that may be evaluated in this article or claim that may be made by its manufacturer is not guaranteed or endorsed by the publisher.