Electrophysiological evidence for a postperceptual locus of suppression during the attentional blink

When an observer detects a target in a rapid stream of visual stimuli, ther e is a brief period of time during which the detection of subsequent target s is impaired. In this study, event-related potentials (ERPs) were recorded from normal adult observers to determine whether this "attentional blink" reflects a suppression of perceptual processes or an impairment in postperc eptual processes. No suppression was observed during the attentional blink interval for ERP components corresponding to sensory processing (the PI and NI components) or semantic analysis (the N400 component). However, complet e suppression was observed for an ERP component that has been hypothesized to reflect the updating of working memory (the P3 component). Results indic ate that the attentional blink reflects an impairment in a postperceptual s tage of processing.