Convergent prefrontal and nigral projections to the striatum of the rat.

Projections to the striatum from the prefrontal cortex, the substantia nigra's pars compacta (SNC), and the ventral tegmental area (AVT) were examined autoradiographically. These projections converge on the striatum in an organized manner such that the prefrontal areas innervated by AVT project to the same part of the striatum as AVT, and prefrontal areas innervated by SNC project to the same part of the striatum as SNC.