Creating a Walking Sensation for the Seated—A Sensation of Pseudo-walking Expands Peripersonal Space

摘要

Body action such as walking is known to extend the subjective boundaries of peripersonal space (PPS; the space immediately surrounding our body) and to facilitate the processing of audio-tactile multisen-sory stimuli presented within the PPS. However, it is unclear whether the boundaries change when a sensation of walking is induced with no physical body motion. In this study, we presented several vibra-tion patterns on the soles of the feet of seated participants to evoke a sensation of walking, together with an approaching sound toward the body. We measured reaction times for detecting a vibrotactile stimulus on the chest, which was taken as a behavioral proxy for the PPS boundary. Results revealed that a cyclic vibration consisting of lowpass-filtered walking sounds presented at the soles that clearly evoked a sen-sation of walking reduced the reaction times, indicating that the PPS boundary was expanded forward by inducing a sensation of walking.