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The neural mechanisms of top-down attentional control J. B. Hopfinger1, M. H. Buonocore2 & G. R. Mangun3 1. Center for Neuroscience and Department of Psychology, One Shields Ave.,University of California, Davis, Davis, California 95616, USA 2. Department of Radiology, University of California, Davis Medical Center, 4701 X St., Sacramento, California 95817, USA 3. Center for Cognitive Neuroscience, LSRC Bldg., Rm. B203, Duke University, Durham, North Carolina 27708, USA Correspondence should be addressed to G R Mangun. e-mail: mangun@duke.edu Selective visual attention involves dynamic interplay between attentional control systems and sensory brain structures. We used event-related functional magnetic resonance imaging (fMRI) during a cued spatial-attention task to dissociate brain activity related to attentional control from that related to selective processing of target stimuli. Distinct networks were engaged by attention-directing cues versus subsequent targets. Superior frontal, inferior parietal and superior temporal cortex were selectively activated by cues, indicating that these structures are part of a network for voluntary attentional control. This control biased activity in multiple visual cortical areas, resulting in selective sensory processing of relevant visual targets. |
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