Analysis of the structural bases of information processing in the basal ganglia: the spatial organization of thalamocortical projections in the dog brain.

Analysis of the architectonics of the thalamic projection systems of the caudate nucleus, putamen, and nucleus accumbens using axonal transport of retrograde markers was performed to study the morphological substrate for information processing in the striatum of the dog brain. The striatal nuclei contained areas through which segregated conduction of motor (dorsal segments of the caudate nucleus and putamen) and limbic (medial segment of the nucleus accumbens) information could occur, along with areas (ventral segments of the caudate nucleus and putamen, lateral segment of the nucleus accumbens) in which convergent conduction of functionally diverse information processed in the thalamic nuclei could occur. These data make a significant contribution to our understanding of the anatomical aspects of both the functional heterogeneity of the basal ganglia and integrative information processing occurring within them, which underlies the mechanisms organizing adaptive behavior.