It was a pleasure reading the article by Howes et al,1 who report an increase of striatal dopamine activity in patients fulfilling prodromal criteria for schizophrenia. They demonstrate that striatal dopamine activity was correlated with the severity of prodromal symptoms and with the severity of neuropsychological impairment in subjects with at-risk mental states (ARMS). However, as not all of these subjects go on to develop psychosis, Howes et al propose that elevated dopamine activity may also be a correlate of increased vulnerability to psychosis and conclude that presynaptic striatal function may be a promising target for future drug development in the treatment of psychotic disorders.
Simon AE, Umbricht D. Is Elevated Striatal Dopamine Function a Prodromal Sign of Schizophrenia?. Arch Gen Psychiatry. 2009;66(8):915-917. doi:10.1001/archgenpsychiatry.2009.100