title: Attentional suppression of activity in the human visual cortex.
abstract: We have used fMRI to examine the nature of the changes that occur in the human visual cortex when an observer attends to a particular location in the visual image. Previous studies have shown that the magnitude of the response to a visual stimulus is increased when the observer attends to the stimulus. We show that, in addition, attention to a particular location results in a widespread suppression of activity levels at all other locations. This suggests that a key mechanism of attentional modulation may be that spontaneous (baseline) levels of neural activity are adjusted in a position-dependent manner across the entire visual field.
authors.affiliation: Department of Psychology, Royal Holloway, University of London, Egham, UK.
authors.forename: A T
authors.initials: AT
authors.lastname: Smith
authors.forename: K D
authors.initials: KD
authors.lastname: Singh
authors.forename: M W
authors.initials: MW
authors.lastname: Greenlee
mesh_terms: D001288:Attention / Q000502:physiology*; D001931:Brain Mapping; D003118:Color Perception / Q000502:physiology; D003626:Data Display; D005403:Fixation, Ocular / Q000502:physiology; D006801:Humans; D008279:Magnetic Resonance Imaging; D010775:Photic Stimulation; D014793:Visual Cortex / Q000502:physiology*; D014796:Visual Perception / Q000502:physiology