Date: 2007.07.02 (Mon) 14:00-15:15
Place: Kashiwa Campus, General Research Building, Room 630.
Speaker: Hiroyuki Tsubomi
Title: Cortical mechanisms of attentional effect in vision - an fMRI study with individual difference approach -
Keywords: visual attention, attentional effect, individual difference, fMRI, cortical network, structural equation modeling

Affiliation: Research Center for Advanced Science and Technology, The University of Tokyo
Position: Assistant Professor
Disciplines: psychology

Abstract:
Human cortex, a large parallel processing system, seems a capacity limited in nature. Previous behavioral studies have suggested that top-down attention biases visual information processing while its cortical mechanism remains unclear. We reviewed current cognitive neuroscience literatures on neural representation of top-down attention. Furthermore, by applying the structure equation modeling (SEM) to our recent fMRI data derived from the experiment, we found the cortical network of the top-down attention working from the frontal (dosolateral premotor cortex and frontal eye field) down to extrastriate and striate visual cortices via the right intraparietal sulcus. This top-down attentional modulation resolves stimulus competition in early visual cortices by enhancing the task-relevant visual information.

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