Fig. 1.

Structure of the PFC network model. Within the PFC network, excitatory neurons (representing deep-layer pyramidal cells) are interconnected by excitatory synapses on their proximal compartments (prox) while receiving afferent input from other cortices on their distal compartments (dis). An inhibitory unit (INH) provides feedback inhibition. A “striatal” motor unit (MOTOR) receives excitatory input from all PFC “pyramidal cells” and inhibits the “mesencephalic” DA unit, which modulates parameters of PFC neurons and synapses in an activity-dependent manner.