Tactile localization on stretched skin

J Exp Psychol Hum Percept Perform. 2023 Aug;49(8):1175-1179. doi: 10.1037/xhp0001142. Epub 2023 Jun 22.

Abstract

The ability to localize touch on the skin is an important aspect of tactile perception. As our limbs move, the skin stretches flexibly, and research has found that signals specifying stretch affect perception of limb posture. Skin stretch also distorts the relative spatial position of different locations on the skin, posing potential problems for tactile localization. Here, we investigated the effects of skin stretch using an established test of tactile localization on the hand. Twenty participants completed a tactile localization task in no-stretch and stretched conditions, respectively, after giving informed consent. The current study found a clear distal and radial bias in both the no-stretch condition and the stretched condition. Indeed, the distal bias was even larger in the stretched condition than at baseline. Critically, however, this change in distal bias was entirely accounted for by changes in the actual location of stimulus as a result of skin stretch, with no corresponding change in the judged location. Thus, the somatosensory system appears to disregard stretch when calculating the location of tactile stimuli. These results mirror recent findings showing that tactile distance perception also fails to take skin stretch into account. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

MeSH terms

  • Hand
  • Humans
  • Posture
  • Space Perception
  • Touch Perception*
  • Touch*