Flexible invisible-body embodiment in childhood: Reduced sensitivity to visuomotor delay and limb scrambling

Poster Session F - Tuesday, March 10, 2026, 8:00 – 10:00 am PDT, Fairview/Kitsilano Ballrooms

Michiteru Kitazaki¹ (mich@tut.jp), Yuta Yoshida¹, Atsushi Sato², Shoji Itakura³; ¹Toyohashi University of Technology, ²University of Toyama, ³Ritsumeikan University

Children gradually acquire stable internal models of body structure and learn how sensorimotor contingencies support body ownership. We tested whether children and adults differ in how body configuration and visuomotor synchrony shape embodiment toward an invisible avatar interpolated between virtual hands and feet (Kondo et al., Scientific Reports 2018). Twenty-four adults (> 18 years old) and twenty-six children (4-5 years old) performed a ball-reaching task while viewing virtual hands and feet rendered at life size on a large screen like a mirror. Hands and feet motion was tracked with wearable trackers and mapped to the avatar either synchronously or with a 1-s delay. Body configuration was either congruent with the participant’s real limb locations (Normal) or spatially rearranged (Scramble). Each participant completed four counterbalanced conditions (Sync/Delay x Normal/Scramble). After each condition, participants rated body ownership (Q1), the sensation of having an invisible body between the limbs (Q2), and agency over the avatar limbs (Q3) on 5-point Likert scales. Three-way mixed ANOVAs were performed. Subjective embodiment showed clear developmental differences. For ownership (Q1), synchrony significantly increased ratings in adults, whereas children showed little or no synchrony benefit. For invisible-body sensation (Q2) and agency (Q3), the scramble configuration and synchrony significantly reduced ratings in adults, but these reductions were absent in children. These results suggest that children maintain relatively high embodiment even when temporal contingencies or body-structure cues are degraded, indicating greater flexibility or lower precision in integrating body configuration and sensorimotor timing when constructing a coherent bodily self-consciousness.

Topic Area: PERCEPTION & ACTION: Development & aging