September 2011
Volume 11, Issue 11
Vision Sciences Society Annual Meeting Abstract  |   September 2011
Strength of the adapter signal, not adapter discriminability, produces reduced facial expression after-effect in crowding
Author Affiliations
  • Hong Xu
    Division of Psychology, Nanyang Technological University, Singapore
  • Leila Montaser-Kouhsari
    Division of the Humanities and Social Sciences, California Institute of Technology, USA
  • Pan Liu
    Division of Psychology, Nanyang Technological University, Singapore
Journal of Vision September 2011, Vol.11, 608. doi:10.1167/11.11.608
  • Views
  • Share
  • Tools
    • Alerts
      This feature is available to authenticated users only.
      Sign In or Create an Account ×
    • Get Citation

      Hong Xu, Leila Montaser-Kouhsari, Pan Liu; Strength of the adapter signal, not adapter discriminability, produces reduced facial expression after-effect in crowding. Journal of Vision 2011;11(11):608. doi: 10.1167/11.11.608.

      Download citation file:

      © ARVO (1962-2015); The Authors (2016-present)

  • Supplements

Crowding, in which a target stimulus is presented with similar flankers, not only impairs the discriminability of the target but also reduces its power to generate adaptation effects. However, little is known about the causes of this reduced adaptation with crowding, especially for the facial expression after-effect. We generated a set of original caricature faces each made of 6 facial features (2 eyebrows, 2 eyes, nose and mouth). The shape of the mouth was varied from concave to convex gradually, signaling the facial expression from sad to happy. We then moved the facial features of the original caricature face (f) closer to the mouth; feature crowded (ffc), or minimized the face contour, contour crowded (fcc), to make the discrimination of mouth harder. In experiment 1, using the above-mentioned stimuli, we tested the crowding effect by asking subjects to judge whether the face stimulus was a sad or happy face. In experiment 2, we used f, ffc or fcc face stimuli with happy expression as an adapter and f as a test. The subjects' task was to judge whether the test face was sad or happy. Only contour crowding in contrast to feature crowding significantly impaired the facial expression discrimination. Yet both feature-crowded or contour-crowded caricature faces produced a facial expression after-effect when utilized as adapters. Compared to a control condition with a non-crowded adapter, contour crowding and surprisingly feature crowding reduced the after-effect significantly (p < 0.001, p = 0.04 respectively). Given that only contour crowding impaired the discriminability of the adapter, the reduced adaptation for the feature crowding condition argues against poor adapter discriminability as the source of the weakened aftereffect. Instead, our results suggest that the strength of the facial expression after-effect depends on the strength of the adapter signal.

HSS - RG1 given to HX. 

This PDF is available to Subscribers Only

Sign in or purchase a subscription to access this content. ×

You must be signed into an individual account to use this feature.