Positive vs. Negative Schizophrenia
In general a malfunction of dopamine pathway. Positive symptoms (VTA-mesolimbic projections) are the presence of abnormal behavior, delusions, and hallucinationsc caused by hyperdopamine transmission to D2 receptors mostly. Treat with antipsychotic drugs (APD) which are D2 receptor antagonists. Negative symptoms (VTA-mesocortical projection) are absence of normal social behavior such as apathy, avolition, anhedonia, alogia, and inappropriate affect caused by low dopamine activity. These chronic symptoms do not respond to APD and are difficult to treat.