Bridging the Senses: An EEG and fMRI co-registration study of auditory, somatosensory and visual multisensory processes
Single Paper Presentation

Manuel Gomez-Ramirez
Cognitive Neuroscience Program of The City College of the City University of New York

Marina Shpaner
Cognitive Neuroscience Program of The City College of the City University of New York

Simon Kelly
Cogntive Neurophysiology Lab of the Nathan S. Kline Institute

Meredith Theeman
Enviormental Psychology program of the City University of New York

Lars Ross
Cognitive Neuroscience Program of The City College of the City University of New York

Aaron Krakowski
Cognitive Neuroscience Program of The City College of the City University of New York

John Foxe
Cognitive Neuroscience Program of The City College of the City University of New York

     Abstract ID Number: 199
     Full text: Not available
     Last modified: March 21, 2006
     Presentation date: 06/21/2006 8:30 AM in Hamilton Building, McNeil Theatre
     (View Schedule)

Abstract
The prevailing model of how multisensory integration effects occur is that different sensory inputs emanating from an entity are analyzed through their respective unisensory processing streams after which they are combined in higher-order ‘multisensory’ regions of the cortex. To date, most studies investigating multisensory integration processes have only been carried-out using stimuli coming from only two modalities. As a consequence, a direct comparison of the latency and neuronal sources of multisensory integration effects between all the different senses is not possible. Here, we investigated the latency and topographical differences of multisensory integration processes between the auditory, somatosensory and visual modalities. The ERP evidence reveals distinct multisensory integration sites for the different pairings of multisensory stimuli. Earlier integration effects were observed for the auditory and somatosensory multisensory stimuli. Topographical and source analyses techniques localize this integration effect to regions over auditory cortices. Similarly, the fMRI data localized this effect to areas posterior to primary auditory cortex. This result suggests that auditory and somatosensory inputs may have direct connections at relatively early stages of stimulus processing and provides strong evidence against the prevailing model of higher-order processing of multisensory stimuli.