Distributed Cortical Phase Synchronization in the EEG Reveals Parallel Attention and Working Memory Processes Involved in the Attentional Blink.

ABSTRACT

Attentional blink (AB) describes a visuo-perceptual phenomenon in which the second of 2 targets within a rapid serial visual presentation stream is not detected. There are several cognitive models attempting to explain the fundamentals of this information processing bottleneck. Here, we used electroencephalographic recordings and the analysis of interregional phase synchronization of rhythmical brain activity to investigate the neural bases of the AB. By investigating the time course of interregional phase synchronization separately for trials in which participants failed to report the second target correctly (AB trials) and trials in which no AB occurred, and by clustering interregional connections based on their functional similarity, it was possible to define several distinct cortical networks. Analyzing these networks comprising phase synchronization--over a large spectrum of brain frequencies from theta to gamma activity--it was possible to identify neural correlates for cognitive subfunctions involved in the AB, such as the encoding of targets into working memory, tuning of attentional filters, and the recruitment of general cognitive resources. This parallel activation of functionally distinct neural processes substantiates the eligibility of several cognitive models on the AB.