PSYC 211 Lecture Notes - Lecture 55: Nucleus Accumbens, Mesolimbic Pathway, Attention Deficit Hyperactivity Disorder
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Ct scans of 80 chronic schizophrenic patients and 66 age matches controls. The researchers were blind to the patient"s diagnoses when they measured the area of lateral ventricles. Ventricle size of schizophrenic patients was twice as great as that of normal control subjects. Role of the prefrontal cortex schizophrenia is associated with abnormalities in the prefrontal cortex. Phencyclidine (pcp) and ketamine (nmda receptor antagonists) elicits the full range of symptoms of schizophrenia. Monkeys with prefrontal lesions also show impairments in this task. Atypical antipsychotics improve performance of pcp treated monkeys. Dopamine and nmda receptors are intimately related: nmda receptor activation triggers the insertion of dopamine receptors into the membranes of dendritic spines (flood of da receptors, activation of dopamine receptors increases nmda receptor efficacy. Thus, by inhibiting nmda receptors, pcp suppresses prefrontal activity either directly or indirectly via dopamine receptors. Prefrontal hypo-activity causes hyperactivity of the mesolimbic dopamine neurons.