Shifting visual attention in space: an electrophysiological analysis using high spatial resolution mapping

摘要: Abstract Objectives : Evidence from cortical electrophysiology and functional imaging converges on the view that visual spatial selective attention results in a facilitation of early sensory processing structures. Little is known, however, about neural control processes lead to this facilitation. The present study was aimed at further investigating these their correlates by analyzing high resolution maps brain activity were evoked attention-directing cues, but occurred prior presentation target stimulus. Methods Subjects ( n =14) presented with central arrow cues instructed them attend covertly either left or right field location order compare two subsequent stimuli simultaneously location. On half trials, targets cued location, while other half, opposite had respond via button press 16% trials when identical. Event-related potentials (ERPs) recorded 92 scalp electrodes which allowed sufficiently finegrained analysis regional specificity ERP components. Results In response an initial component over occipital-parietal electrode sites consistent involvement posterior-parietal cortex, perhaps step attentional orienting. A second lateral-prefrontal cortex voluntary maintenance attention, function known be subserved frontal late narrowly focussed occipital-temporal most plausibly related activation parts ventral extrastriate cortex. Conclusions data support current voluntarily orienting space leads top-down modulations excitability regions initiated mediated