• Animal cells and systems
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• v.8 no.4
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• pp.319-328
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• 2004

Extrinsic connections between the cortex of the superior temporal sulcus (STS) and the ventral striatum in pigtail macaque monkeys (Macacca nemestrina) were studied by injection of retrograde tracers into the ventromedial caudate nucleus, the ventral and central shells of the nucleus accumbens (NA), the dorsal core of the NA, and the ventrolateral putamen. In the present study, we demonstrate that the projections from the unimodal (area TAa, IPa, TEa, and TEm) and the multimodal (area TPO and PGa) sensory association areas in the STS mainly terminate in the ventromedial caudate nucleus as well as in the ventral and central shells of the NA. However, there are only few projections to the dorsal core of the NA and the ventrolateral putamen from the sensory association cortex in the STS. Based on these differential neural connections between the subterritories of the ventral striatum and the sensory association areas, the ventromedial caudate nucleus and the shells of NA appear to be major integration sites for sensory input from the STS and functionally different from the dorsal core of NA and the ventrolateral putamen.

• Animal cells and systems
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• v.7 no.4
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• pp.317-325
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• 2003

Corticostriatal connections of auditory areas within the rostral and caudal portions of the superior temporal gyrus (STG) and in the supratemporal plane(STP) of pigtail macaque (Macacca nemestrina) were studied with particular emphasis on specific projections to the ventral striatum. Retrograde tracers were Injected into five different regions of the ventral striatum such as the ventromedial caudate nucleus, ventral shell, central shell, dorsal core of the nucleus accumbens (NA), and ventrolateral putamen to Identify the cells of origin. There were only few projections from the auditory areas in the STP to the ventral striatum. However, the association (or belt) areas of the STG collectively had widespread corticostriatal projections characterized by differential topographic distributions. The rostral parts of the STG strongly projected to the ventromedial caudate nucleus. The midportion of the STG also projected to the same ventral striatal regions, but the connections were relatively less extensive. Interestingly, the caudal portion of the STG had no connection to all subregions of the ventral striatum. These differential patterns of corticostriatal connectivity suggest that the ventromedial caudate nucleus would be a major auditory convergence area and mainly involved in sound recognition rather than spatial localization of sound sources.

• Animal cells and systems
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• v.7 no.3
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• pp.237-248
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• 2003

Recent evidence on behaviors in macaque monkeys indicate that the medial temporal cortical areas such as the entorhinal cortex (EC), perirhinal cortex, and parahippocampal cortex (PHC) are importantly involved in limbic and sensory memory function. Neuroanatomical studies also have demonstrated that the medial temporal cortical areas are connected with the ventral striatum, although comparatively little is known about the precise topography of these connections. We investigated the topographic organization of connections between the medial temporal cortical areas and the ventral striatum by placing retrograde tracers into five different regions of the ventral striatum: the ventromedial caudate nucleus, ventral shell, central shell, dorsal core of the nucleus accumbens (NA), and ventrolateral putamen. We found that the shell of the NA was the main projection site from the medial temporal cortical areas. Within the shell of the NA, there were also differential connections: EC diffusely innervates shell of the NA, while the projections from the perirhinal cortex and PHC concentrate on the ventral shell of the NA. Taken together, it is possible that the ventral shell of the NA is the main integration site of the limbic and sensory memory coming from the EC, perirhinal cortex, and PHC.