and dACC, terminals from the dPFC are located primarily in the head of the caudate and the medial, ventral, and central parts of the rostral putamen (figure 4d). The dorsolateral portion of the putamen contains fewer terminating axons. Consistent with input from this cortical area, cells in the head of the caudate nucleus demonstrate spike-firing activity during the delayed portion of the task. This activity resembles that observed in the dPFC.98 Furthermore, imaging studies support the idea that the head of the caudate is instrumental in delayed tasks, particularly in specific working memory tasks.99 Finally, lesions of the caudate nucleus in both human and nonhuman primates produce deficits in working memory, as measured by delayed response tasks.100 Taken together, the caudate nucleus—in particular, the head of the caudate—is involved in working memory and strategic planning processes, working together with the dPFC in mediating this function.
