Prefrontal Serotonin Depletion Affects Reversal Learning But Not Attentional Set Shifting

摘要: Recently, we have shown that serotonin (5-HT) depletion from the prefrontal cortex (PFC) of marmoset monkey impairs performance on a serial discrimination reversal (SDR) task, resulting in perseverative responding to previously correct stimulus (Clarke et al., 2004). This pattern impairment is just one example inflexible seen after damage PFC, with SDR task being dependent integrity orbitofrontal cortex. However, contribution 5-HT other forms flexible responding, such as attentional set shifting, an ability lateral PFC (Dias 1996a), unknown. The present study addresses this issue by examining effects 5,7-dihydroxytryptamine-induced depletions shift attention between two perceptual dimensions compound visual (extradimensional shift). Monkeys selective lesions, despite impaired their reverse stimulus-reward association, were unimpaired make extradimensional when compared sham-operated controls. These findings suggest critical for at level changing contingencies but not essential higher-order shifting set. Thus, psychological functions different loci within are differentially sensitive serotonergic modulation, finding relevance our understanding cognitive inflexibility apparent disorders obsessive-compulsive disorder and schizophrenia.