Prefrontal neurons in networks of executive memory

The neuronal networks of the frontal lobe that represent motor or executive memories are probably the same networks that cooperate with other cerebral structures in the temporal organization of behavior, The prefrontal cortex , at the top of the perception-action cycle, plays a critical role in the m ediation of contingencies of action across time, an essential aspect of tem poral organization, That role of cross-temporal mediation is based on the i nterplay of two short-term cognitive functions: one retrospective, of short -term active perceptual memory, and the other prospective, of attentive set (or active motor memory), Both appear represented in the neuronal populati ons of dorsolateral prefrontal cortex. At least one of the mechanisms for t he retention of active memory of either kind seems to be the reentry of exc itability through recurrent cortical circuits. With those two complementary and temporally symmetrical cognitive functions of active memory for the se nsory past and for the motor future, the prefrontal cortex seems to secure the temporal closure at the top of the perception-action cycle, (C) 2000 El sevier Science Inc.