The prefrontal cortex: Response selection or maintenance within working memory?

It is controversial whether the dorsolateral prefrontal cortex is involved in the maintenance of items in working memory or in the selection of respon ses. We used event-related functional magnetic resonance imaging to study t he performance of a spatial working memory task by humans, We distinguished the maintenance of spatial items from the selection of an item from memory to guide a response. Selection, but not maintenance, was associated with a ctivation of prefrontal area 46 of the dorsal lateral prefrontal cortex, In contrast, maintenance was associated with activation of prefrontal area 8 and the intraparietal cortex The results support a role for the dorsal pref rontal cortex in the selection of representations. ntis accounts for the fa ct that this area is activated both when subjects select between items on w orking memory tasks and when they freely select between movements on tasks of willed action.