Temporal modulation of tactile perception during balance control

Summary

Somatosensory feedback is essential for motor control, yet sensations from one’s own movements are often suppressed. Despite extensive research on movement-induced tactile suppression, its mechanisms remain unclear. Most studies focus on simple upper-limb movements, leaving the generalization to other body parts unexplored. This study examines tactile processing on the lower limb during balance control by varying feedback processing demands. Participants experienced visual perturbations in a virtual room challenging their posture. Tactile sensitivity was assessed using vibrotactile stimuli to the lower leg at different times around the perturbation. We found that postural behavior is both predictively tuned before and reactively adjusted to expected perturbations. Our results provide evidence that tactile sensitivity changes according to feedback processing demands on the lower limb. Such dynamic sensory modulation could reflect the continuous up- and down-regulation of feedback signals to accomplish the task at hand.