In addition to convergence between vmPFC, dACC, and OFC dense terminals, projections from dACC and OFC also converge with inputs from the dPFC, demonstrating that functionally diverse PFC projections also converge in the striatum (Figure 5b). At rostral levels, dPFC terminals converge with those from both the dACC and OFC, although each cortical projection also occupies its own territory. Here, projections from all PFC areas occupy a central region, the different cortical projections extending into nonoverlapping zones. Convergence is less prominent caudally, with almost complete separation of the dense terminals from the dPFC and dACC/OFC just rostral to the anterior commissure. Importantly, convergence does not take place only at the boundaries or edges of different functional domains. Rather, there are dense clusters of invading terminals from the dPFC embedded deep within the dense projection field of the OFC14,94 Since MSNs have a dendritic field spanning 0.5 mm,107 the area of convergence is likely to be larger than that estimated solely on the basis of the relationship between the afferent projections.
