The strategic management and structural organization of working memory distinct roles for D1 and D2 dopamine receptors

Dopamine is critical for the modulation of several adaptive cognitive functions, including reinforcement learning, coordination, and various reward-motivated behaviors. Within the prefrontal cortex (PFC), dopamine is thought to be involved in the modulation of attention and working memory in a motivation-dependent fashion, however the precise mechanisms underlying these functions have not been fully elucidated. D1 and D2-type dopamine receptors are located in different subcellular regions and differentially modulate the firing rates of PFC pyramidal neurons, and are therefore thought to differentially regulate PFC-mediated cognitive functions. In this paper, a) the various roles of dopamine in these functions are reviewed, b) their underlying mechanisms examined, and c) a model for the dopaminergic modulation in the organization of working memory representations is proposed within the functional morphological framework of the PFC pyramidal neuron (originally proposed by Goldman-Rakic)