Children-Friendly Auditory Version of the Somatic Rubber Hand Illusion to Study the Interaction between Proprioception and Audition during Development

In this study, we adapted the Somatic version of the Rubber Hand Illusion paradigm to investigate the effect of auditory stimulation synchronized on tactile cues during development. Children aged six to eleven years old were asked to estimate the position of their right hand before and after a period of synchronous stimulation. This could involve tactile stimulation alone or combined audio-tactile stimulation. In the tactile-only condition, the experimenter brushed the participant's right hand while simultaneously guiding the participant's left hand to brush the dummy hand. The audio-tactile condition was similar to the tactile one, the only difference was that a single sound accompanied each brushstroke, synchronized with the tactile stimulation. Following each trial, Proprioceptive Drift (a shift in the perceived position of the child's hand) and subjective experience of the illusion (aka the impression that one was brushing their own hand) were measured. Children displayed Proprioceptive Drift across the examined age range, with age being a significant predictor of the effect. Subjective experience of the illusion was also significant, but resulted to be constant across development. No effect of auditory cues was observed regardless of age, suggesting that audition does not modulate proprioception nor the subjective experience of the illusion in this age group. The present study successfully validates a children-friendly auditory version of the Somatic Rubber Hand illusion that can be used to study the interaction between proprioception and audition during typical and atypical development.