Prefrontal Cortex Modulation during Anticipation of Working Memory Demands as Revealed by Magnetoencephalography.

Mario Altamura,Brita Elvevåg,Terry E Goldberg,Richard Coppola,Tom Holroyd,Frederick W Carver,Daniel R Weinberger

doi:10.1155/2010/840416

Abstract

During the anticipation of task demands frontal control is involved in the assembly of stimulus-response mappings based on current goals. It is not clear whether prefrontal modulations occur in higher-order cortical regions, likely reflecting cognitive anticipation processes. The goal of this paper was to investigate prefrontal modulation during anticipation of upcoming working memory demands as revealed by magnetoencephalography (MEG). Twenty healthy volunteers underwent MEG while they performed a variation of the Sternberg Working Memory (WM) task. Beta band (14–30 Hz) SAM (Synthetic Aperture Magnetometry) analysis was performed. During the preparatory periods there was an increase in beta power (event-related synchronization) in dorsolateral prefrontal cortex (DLPFC) bilaterally, left inferior prefrontal gyrus, left parietal, and temporal areas. Our results provide support for the hypothesis that, during preparatory states, the prefrontal cortex is important for biasing higher order brain regions that are going to be engaged in the upcoming task.

Highlights

While performing a task, attention is allocated to each successive stage of task processing, including the anticipation of incoming events
During the preparatory periods there was an increase in beta power in dorsolateral prefrontal cortex (DLPFC) bilaterally, left inferior prefrontal gyrus, left parietal, and temporal areas
Our results provide support for the hypothesis that, during preparatory states, the prefrontal cortex is important for biasing higher order brain regions that are going to be engaged in the upcoming task

Summary

Introduction

Attention is allocated to each successive stage of task processing, including the anticipation of incoming events. Neuroimaging studies have examined anticipation in a variety of controlled paradigms in which a predesignated response is elicited by an upcoming imperative stimulus [2]. These studies suggest that the function of the prefrontal cortex (PFC) is the assembly on an ad hoc basis of stimulus– response mappings based on current goals. Few studies have examined anticipation during complex task preparation [3,4,5]. It is not clear whether prefrontal modulations occur in higher order cortical regions, likely reflecting cognitive anticipation processes

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