Dopamine and the neural circuitry of primate prefrontal cortex: implications for schizophrenia research

Dopaminergic systems have been implicated in the pathophysiology of schizophrenia; the prefrontal cortex may be a site of dysfunction in this disorder. Until recently, however, relatively little was known about the organization of dopaminergic afferents, or the relationship of those axons to other elements of neural circuitry in the expanded and highly differentiated prefrontal cortex of primates. In this paper we review recent studies demonstrating that monkey prefrontal cortex is innervated by dopaminergic axons in a highly specific regional and laminar fashion. These findings are considered in the context of the organization of other neural systems in monkey prefrontal cortex and with regard to the extent to which they represent the organization of human prefrontal cortex. The resulting model of prefrontal cortical circuitry is then discussed in terms of the ways in which that circuitry might be disrupted in schizophrenia.