The prefrontal cortex of the primate: A synopsis

The prefrontal cortex is one of the latest regions of the neocortex to deve lop, in both phylogeny and ontogeny. In the primate, the prefrontal cortex is anatomically divided into three major sectors: medial, orbital (or infer ior), and dorsolateral. The dorsolateral sector is the association cortex o f the convexity of the frontal lobe. Phylogenetically and ontogenetically, this part of the prefrontal cortex is the one to develop last and most. It is the neural substrate of the higher cognitive functions that reach their maximum development in the human brain. The most general and distinctive fu nction of the dorsolateral prefrontal cortex is the temporal organization o f goal-directed actions. In the human, this role extends to the domains of speech and reasoning. Two temporally symmetrical and mutually complementary cognitive functions-one retrospective and: the other prospective-support t hat general prefrontal function of temporal organization: (1) active short- term memory also called working memory; (2) prospective or preparatory set. The dorsolateral prefrontal cortex interacts with other cortical and subco rtical structures in those two time-bridging functions at the basis of the temporal organization of behavior.