ENDURING COGNITIVE DEFICITS AND CORTICAL DOPAMINE DYSFUNCTION IN MONKEYS AFTER LONG-TERM ADMINISTRATION OF PHENCYCLIDINE

The effects of the psychotomimetic drug phencyclidine on the neurochem istry and function of the prefrontal cortex in vervet monkeys were inv estigated, Monkeys treated with phencyclidine twice a day for 14 days displayed performance deficits on a task that was sensitive to prefron tal cortex function; the deficits were ameliorated by the atypical ant ipsychotic drug clozapine, Repeated exposure to phencyclidine caused a reduction in both basal and evoked dopamine utilization in the dorsol ateral prefrontal cortex, a brain region that has long been associated with cognitive function, Behavioral deficits and decreased dopamine u tilization remained after phencyclidine treatment was stopped, an indi cation that these effects were not simply due to direct drug effects. The data suggest that repeated administration of phencyclidine in monk eys may be useful for studying psychiatric disorders associated with c ognitive dysfunction and dopamine hypofunction in the prefrontal corte x, particularly schizophrenia.