Functional organization of the primate prefrontal cortex for memory

Summary form only given. Although it is generally agreed that the lateral prefrontal cortex plays an important role in memory, a precise characterization of the role of the different prefrontal regions in memory has proven elusive. Studies on nonhuman primates show that lesions of the mid-dorsolateral prefrontal cortex give rise to severe impairments on the capacity to monitor information in working memory. Functional neuroimaging studies have provided support to the idea that increased monitoring demands in experimental tasks relative to the control tasks result in increased activity in the mid-dorsolateral prefrontal region regardless of the nature of the stimulus material. By contrast, recent experiments indicate that the mid-ventrolateral prefrontal cortex is selectively involved in the active retrieval of information from posterior cortical association areas. Active retrieval is required when stimuli in memory do not bear stable relations to each other and therefore retrieval cannot be automatically driven by stable and unambiguous context relations.