The perceived size of the implicit representation of the dorsum and palm of the hand

PLoS One. 2020 Mar 23;15(3):e0230624. doi: 10.1371/journal.pone.0230624. eCollection 2020.

Abstract

The perception of the body and its parts has traditionally been studied using the conscious body image. Here, we determine the implicit representation of the hand. Participants were sequentially shown two life-size images of either the dorsal or palmar surface of their hand. In one interval either the horizontal or vertical dimension of the image was varied using an adaptive staircase, while the other interval contained the full-size, undistorted image. Participants reported which image most closely matched their hand. The staircase honed in on the distorted image that was equally likely to be judged as matching their own hand as the accurate image. The implicit representation was taken as midway between these two images. The experiment was repeated with different hand orientations. Perceived width depended on the orientation, with differences found between the upright and right orientations. Interestingly, the perceived length of the dorsum and palm were different from each other-length of the dorsum was overestimated whereas palm length was perceived accurately. This study reveals distortions of the implicit representation of the hands in healthy individuals.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Body Image / psychology
  • Body Size*
  • Female
  • Hand / anatomy & histology*
  • Humans
  • Male
  • Perception*

Grants and funding

This work was supported by the Natural Sciences and Engineering Council of Canada (NSERC) grant #46271-2015 to LRH. SD was supported by a PGS-D3 NSERC graduate scholarship and an NSERC CREATE grant. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.