Attention and maintenance in working memory: a neurophysiological review

Abstract

An abundance of theoretical models concur that attention plays a central role in working memory, for both information processing and maintenance. Specifically, it has been suggested that maintenance in working memory depends on attentional refreshing, the mechanics and precise functioning of which are not well understood. The present article reviews the contributions made by neurophysiological studies to this understanding. Functional Magnetic Resonance Imaging (fMRI) studies have shown that specific cerebral structures are activated during refreshing. Moreover, fMRI data support the hypothesis of a mechanism involved in the maintenance of different types of information that trigger the reactivation of sensorial properties of memory traces, and furthermore offer insights into three potentially distinct components of refreshing: initiation, serial order maintenance processes, and refreshing per se. Electrophysiological studies demonstrate that a close relationship exists between attention and maintenance in working memory and contribute to an understanding of time steps involved in attentional refreshing. The reviewed studies support the existence of a maintenance mechanism that is based on attention and that has the functional properties attributed to attentional refreshing, allowing for the maintenance of information regardless of type (verbal or visual) or the sensorial modality being presented.