CORTICOSTRIATAL CONNECTIONS OF THE SUPERIOR TEMPORAL REGION IN RHESUS-MONKEYS

Corticostriatal connections of auditory areas within the supratemporal plane and in rostral and caudal portions of the superior temporal gyr us were studied by the autoradiographic anterograde tracing technique. The results show that the primary auditory cortex has limited project ions to the caudoventral putamen and to the tail of the caudate nucleu s. Ln contrast, the second auditory area within the circular sulcus ha s connections to the rostral and the caudal putamen and to the body of the caudate nucleus and the tail. The association areas of the superi or temporal gyrus collectively have widespread corticostriatal project ions characterized by differential topographic distributions. The rost ral part of the gyrus projects to ventral portions of the head of the caudate nucleus and of the body and to the tail. In addition, there ar e connections to rostroventral and caudoventral portions of the putame n. The mid-portion of the gyrus projects to similar striatal regions, but the connections to the head of the caudate nucleus are less extens ive. Compared with the rostral and middle parts of the superior tempor al gyrus, the caudal portion has little connectivity to the tail of th e caudate nucleus. It projects more dorsally within the head and the b ody and also more dorsally within the caudal putamen. These differenti al patterns of corticostriatal connectivity are consistent with functi onal specialization at the cortical level. (C) 1998 Wiley-Liss, Inc.