Location of Repository

Photographic but not line-drawn faces show early perceptual neural sensitivity to eye gaze direction

By Alejandra eRossi, Francisco Javier Parada, Francisco Javier Parada, Marianne eLatinus, Marianne eLatinus and Aina ePuce

Abstract

Our brains readily decode facial movements and changes in social attention, reflected in earlier and larger N170 event-related potentials (ERPs) to viewing gaze aversions vs. direct gaze in real faces (Puce et al. 2000). In contrast, gaze aversions in line-drawn faces do not produce these N170 differences (Rossi et al., 2014), suggesting that physical stimulus properties or experimental context may drive these effects. Here we investigated the role of stimulus-induced context on neurophysiological responses to dynamic gaze. Sixteen healthy adults viewed line-drawn and real faces, with dynamic eye aversion and direct gaze transitions, and control stimuli (scrambled arrays and checkerboards) while continuous electroencephalographic (EEG) activity was recorded. EEG data from 2 temporo-occipital clusters of 9 electrodes in each hemisphere where N170 activity is known to be maximal were selected for analysis. N170 peak amplitude and latency, and temporal dynamics from event-related spectral perturbations (ERSPs) were measured in 16 healthy subjects. Real faces generated larger N170s for averted vs. direct gaze motion, however, N170s to real and direct gaze were as large as those to respective controls. N170 amplitude did not differ across line-drawn gaze changes. Overall, bilateral mean gamma power changes for faces relative to control stimuli occurred between 150-350 ms, potentially reflecting signal detection of facial motion.Our data indicate that experimental context does not drive N170 differences to viewed gaze changes. Low-level stimulus properties, such as the high sclera/iris contrast change in real eyes likely drive the N170 changes to viewed aversive movements

Topics: Apparent motion, N170, gaze aversion, real faces, line-drawn faces
Publisher: Frontiers Media S.A.
Year: 2015
DOI identifier: 10.3389/fnhum.2015.00185
OAI identifier: oai:doaj.org/article:07dffb4fb62546a69a7d7cf33f4a30db
Journal:
Download PDF:
Sorry, we are unable to provide the full text but you may find it at the following location(s):
  • https://doaj.org/toc/1662-5161 (external link)
  • http://journal.frontiersin.org... (external link)
  • https://doaj.org/article/07dff... (external link)
  • Suggested articles


    To submit an update or takedown request for this paper, please submit an Update/Correction/Removal Request.