Push-Pull Mechanism of Selective Attention in Human Extrastriate Cortex

摘要: Selective attention operates in visual cortex by facilitating processing of selected stimuli and filtering out unwanted information from nearby distracters over circumscribed regions space. The neural representation unattended outside this focus is less well understood. We studied the fate using functional magnetic resonance imaging dissociating activity evoked attended (target) presented to periphery a hemifield (distracter) simultaneously corresponding location contralateral hemifield. Subjects covertly directed series target performed either low or high attentional-load search task on stream otherwise identical stimuli. With task, target-search-related increased with increasing attentional load, whereas distracter-related decreased load areas V4 TEO but not early V1 V2. This finding presents evidence for load-dependent push-pull mechanism selective that large portions field at intermediate stages. appeared be controlled distributed frontoparietal network brain reflected processes related selection during spatially attention.