What resolves this contention: Strict segregation versus convergence: the canon…

What resolves this contention: Strict segregation versus convergence: the canonical five-loop schema posits clean parallelism, while later anterograde tracing demonstrates extensive within-zone convergence among related cortical eye fields. / Cortico-basal ganglia circuits are organized into five strictly parallel and segregated functional loops corresponding to motor, oculomotor, dorsolateral prefrontal, lateral orbitofrontal, and anterior cingulate channels. / Parallel processing is not the exclusive principle of organization, because corticostriatal projections from FEF and SEF show major patch-overlap convergence within the caudate, with both convergence and divergence patterns evident.