Autoradiograms of total [³H]mazindol binding in control (Normal), asymptomatic (Asymp.), acutely symptomatic (Acute Symp.), and chronically symptomatic (Chronic Symp.) monkeys. The top row shows the rostral striatum, including the caudate nucleus, putamen, and nucleus accumbens. The middle row shows the mid level of the striatum, including the caudate nucleus, putamen, and external segment of the globus pallidus. The bottom rowshows the caudal striatum, including the putamen, body of the caudate nucleus, and both the internal and external segments of the globus pallidus. Both symptomatic groups show similar losses in total [³H]mazindol binding compared with controls, whereas the asymptomatic group shows less extensive losses in medial and ventral regions.