THE NEURAL BASIS OF THE CENTRAL EXECUTIVE SYSTEM OF WORKING-MEMORY

Working memory refers to a system for temporary storage and manipulati on of information in the brain, a function critical for a wide range o f cognitive operations. It has been proposed that working memory inclu des a central executive system (CES) to control attention and informat ion flow to and from verbal and spatial short-term memory buffers(1). Although the prefrontal cortex is activated during both verbal and spa tial passive working memory tasks(2-8), the brain regions involved in the CES component of working memory have not been identified. We have used functional magnetic resonance imaging (fMRI) to examine brain act ivation during the concurrent performance of two tasks, which is expec ted to engage the CES. Activation of the prefrontal cortex was observe d when both tasks are performed together, but not when they are perfor med separately. These results support the view that the prefrontal cor tex is involved in human working memory.