Structural basis of the interaction of the limbic and motor systems in the striopallidum.

The results regarding the topical organization of the projections from the nuclei of the amygdaloid body, the ventral tegmental area, and the substantia nigra in the striopallidum were generalized and compared in a study carried out on 125 cats, using the method of retrograde axonal transport of horseradish peroxidase and fluorochromes. Limbic and motor areas were identified in the basal ganglia with a predominance of projections, respectively, from the subcortical structures belonging to the limbic system, or from formations relating to a greater degree to motoric activity. In addition to this, the overlapping of terminals of the fields of the initial neurons of these and other structures was established in substantial areas of the striopallidum. The data obtained regarding the organization of projections of functionally varied subcortical formations to the striopallidum suggest that it may be regarded as the structural basis of the functional heterogeneity of the basal ganglia and of the interaction of the motor and limbic systems in them.