THE ACCUMBENS - BEYOND THE CORE-SHELL DICHOTOMY

This article highlights recent discoveries related to the accumbens an d closely associated structures, with special reference to their impor tance in neuropsychiatry. The development of ''striatal patches'' in t he accumbens is reviewed in a series of pictures. Neuronal ensembles a re discussed as potentially important functional-anatomical units. Att ention is also drawn to recent discoveries related to the neuronal cir cuits that the primate accumbens establishes with the mesencephalic do pamine system. On the basis of histological and neurochemical differen ces, the accumbens has been divided into core and shell compartments. In the context of this article, the shell, which is an especially dive rsified part of the accumbens, is the subject of special attention bec ause of its close relation to the extended amygdala and distinctive re sponse to antipsychotic and psychoactive drugs.