Whole-body immobilization modulates visuotactile interaction.

Area of Science:

• Neuroscience
• Perception
• Human Body Interaction

Background:

• Peripersonal space (PPS) is the immediate space surrounding the body.
• Previous research showed hand immobilization shrinks hand-centered PPS.
• The impact of whole-body immobilization on other body parts' PPS remains largely unknown.

Purpose of the Study:

• To investigate the effect of whole-body immobilization on trunk-centered peripersonal space.
• To differentiate the effects of body immobilization from box embodiment on PPS.
• To examine visuotactile interactions within the trunk-centered PPS.

Main Methods:

• Two experiments were conducted using a tactile stimulus on the chest and an approaching visual probe.
• Experiment 1 compared trunk-centered PPS with and without a large box.
• Experiment 2 manipulated box size (large vs. small) to assess box embodiment effects.
• Visual facilitation of tactile detection and perceived body immobilization were measured.

Main Results:

• Visual facilitation of tactile detection was greater when the body was within a box compared to without.
• A smaller box led to greater visual facilitation than a larger box.
• Perceived body immobilization was stronger in the with-box condition and with a smaller box.

Conclusions:

• Body immobilization significantly enhances visuotactile interactions within the trunk-centered peripersonal space.
• The degree of body immobilization, rather than the mere presence or size of a confining box, appears to be the primary driver of enhanced visuotactile interaction.
• These findings contribute to understanding how physical constraints shape our perception of space around the body.