Temporal factors influence on the location of auditory-visual integrative processing in human cortex
Poster Presentation

Xilong Zhi
Kyushu Institute of Technology

Huaying Jin
Ashikaga Institute of Technology

     Abstract ID Number: 112
     Full text: Not available
     Last modified: March 21, 2005

Abstract
Although the recent studies found that the locations of auditory-visual integrative processing in human cortex, under synchronous bimodal stimulation condition, are different from that under bimodal stimuli onset asynchrony (SOA) condition, nothing is known about whether the different temporal gaps of auditory-visual SOA (SOA is unequal zero ms) may influence on the location. To detect this influence, we repeated the classic experiment of Giard and Peronnet’s [J. Cogn. Neuroscience 11:5, 473-490], but visual stimulus onset was earlier 15 ms (experiment 1, SOA 15 ms) and 30 ms (experiment 2, SOA 30 ms) than the auditory stimulus onset. Comparing the interaction effects under SOA 15 ms condition with that under SOA 30 ms condition, the results showed that (1) in prefrontal cortex, the effects may be observed not only under SOA 15 ms condition but also under SOA 30 ms condition, suggest these multisensory cells do not process auditory-visual temporal information, it is consistent with previous study that prefrontal regions specialized in auditory and visual spatial processing; (2) left visual area and right parieto-occipital area were selectively activated under SOA 15 ms condition, right temporal-occipital area and right temporal were activated for SOA 30 ms, revealed that temporal factors of auditory-visual SOA may influence on the integrative processing location, and suggest that these regions are relative to ‘compensation for sound delay in human perception’, and furthermore, support the proposition that the different regions may be set-up to optimize audiovisual integration at different ranges of distance from the observer.