STATISTICS OF GAZE FIXATION DISTRIBUTIONS WITHIN DYNAMIC FACES DURING AUDIOVISUAL SPEECH PERCEPTION
Multiple Paper Presentation

MARTIN PARE
DEPTS OF PHYSIOLOGY AND PSYCHOLOGY

     Abstract ID Number: 11
     Last modified: January 14, 2006
     Presentation date: 06/19/2006 2:00 PM in Hamilton Building, McNeil Theatre
     (View Schedule)

Abstract
The human face is a multifaceted stimulus of particular significance for social communication, including audiovisual speech. To understand better the process of gathering facial information, we examined the spatial distribution of gaze fixations displayed by subjects performing audiovisual speech perception tasks while viewing dynamic talking faces. In a series of experiments, we found that gaze fixations are asymmetrically distributed, influenced by the nature of the task and the perceptual difficulty, but not necessarily correlated with perceptual accuracy. Although gaze tend to be directed more toward the lips of a talker during speech, high spatial frequency information afforded by direct oral foveation is not necessary for the successful processing of visual speech information. When speech intelligibility is decreased with acoustic noise, subjects minimize their gaze fixation distributions around the center of the talker’s face, which constitutes an ideal vantage point to process a face as a whole. These findings show that the process of gathering facial information is structured mostly because of the observer’s strategy rather than the stimulus itself and that it is not restricted to foveal image processing. This work emphasizes the importance of studying face processing with dynamic stimuli to simulate naturalistic communication conditions.

To be Presented at the Following Symposium:
Audio-visual integration subserving sensory-motor and cognitive function
Other papers in this Symposium:

• Douglas Munoz
  Centre for Neuroscience Studies, Queen's University
  OVERT AND COVERT ORIENTING TO COMBINED AUDIO-VISUAL STIMULI
• Lizabeth Romanski
  University of Rochester
  Integration of auditory and visual communication information in the primate prefrontal cortex.
• Gary Paige
  Dept. of Neurobiology & Anatomy
  Babak Razavi
  Biomedical Engineering
  William O'Neill
  Dept. of Neurobiology & Anatomy
  CROSS-SENSORY INTERACTION AND ADAPTATION UNDERLYING SPATIAL LOCALIZATION