Visuo-auditory integration in the monkey: behavioral and neuronal evidences in the primary visual cortex
Poster Presentation

Ye Wang
Cerveau et Cognition, CNRS UMR 5549

Simona Celebrini
Cerveau et Cognition CNRS UMR 5549

Christophe Joufrais
Institut de Recherche en Informatique de Toulouse

Yves Trotter
Cerveau et Cognition CNRS UMR 5549

Pascal Barone
Cerveau et Cognition CNRS UMR 5549

     Abstract ID Number: 35
     Full text: Not available
     Last modified: March 15, 2005

Abstract
Recent human imaging studies have revealed that multisensory interactions can occur in early stages of visual processing, a phenomenon probably mediated by the direct projections observed in the monkey, from auditory areas directly to V1. To investigate the influence of an auditory stimulus on visual responses of V1 neurons, a monkey was trained to maintain a passive central fixation while a peripheral visual or visuo-auditory stimulus was presented. From a population of 47 V1 neurons, there is no difference in the mean latencies or strength of visual responses when comparing visual or visuo-audiory conditions. In a second active task, the monkey was required to orient his gaze toward the visual or visuo-auditory stimulus. Behaviorally, in bimodal compared to visual condition, saccade latencies are significantly 10% shorter. From 48 cells recorded during this saccadic task, visual neurons present a significant reduction in response latencies in visuo-auditory condition compared to visual (mean 63,8 vs. 60,4ms) only when the visual stimulus was at low contrast. No effect was observed at high contrast. These results suggest that the behavioral improvement of performances in visuo-auditory conditions might be partly mediated by an integration of auditory information performed at the level of the primary visual cortex.