The term “executive function” has been used to capture the highest order of cognitive abilities, including the planning, flexibility, organization and regulation necessary for the execution of an appropriate behavior. Executive function, although an elusive cognitive domain, may be highly dependent on working memory, which refers to the temporary storage and manipulation of information. The physiology of working memory is beginning to be mapped in both monkey and human studies at the neuroanatomical and neurochemical levels. Working memory is likely subserved by a distributed network of brain regions in which the prefrontal cortex is critical, subserving the process of maintaining representations across time. There is also a relationship between dopaminergic projections in the brain and working memory. Improved understanding of the physiological basis of executive functioning and working memory will provide a narrower view of prefrontal cortical function and may lead to new therapies in patients with cognitive dysfunction.
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