The nucleus accumbens resides with the ventral forebrain adjacent to where the putamen and head of the caudate become continuous with one another (eFig. 9.99). Afferent axons to the nucleus accumbens come from the amygdala through the amygdalofugal pathway, hippocampal formation by way of the fornix, basal forebrain area from the stria terminalis, and ventral tegmentum through the medial forebrain bundle (eFig. 9.98A–D). Efferent axons leaving the nucleus accumbens project directly to the hypothalamus and globus pallidus and reach nuclei in the brainstem through the medial forebrain bundle. Its connections to the globus pallidus represent an important connection of the limbic system to the motor system. The overall function of the nucleus accumbens is recognized as a gratification center and has been shown to play a role in behaviors related to addiction.