Diencephalic projections from rostral brain in cat. An autoradiographic study.

Following isotope injections in gyrus proreus (cases CT-600 and CT-601), the following nuclei were labelled: reticularis anterior, ventralis anterior, medialis dorsalis, ventralis medialis, medial portions of lateralis posterior, paratenialis and parafascicularis. Following an injection which included the medial precruciate and caudal genualis cortices (CT-625) the projection included: reticularis anterior, anterior medialis, ventralis anterior, ventralis anteromedialis, ventralis medialis, medialis dorsalis (pars paralamellaris), lateralis posterior, and parafascicularis. Thus, the medial precruciate cortex and the gyrus proreus share a number of projections. The most important differences are as follows: medialis dorsali principalis (both its medial magnocellular portion and its lateral parvicellular portion) receives afferents from gyrus proreus, whereas its paralamellar portion receives them from the medial precruciate and genualis cortices; the nucleus anterior medialis receives fibers from the medial precruciate cortex but not from gyrus proreus; a dorsolateral extension of VM, coined here as nucleus ventralis anteromedialis (VAM) receives fibers from medial precruciate but not from proreus cortex. No labelling was found in the hypothalamus, septum, and amygdala following injections in either proreus or medial precruciate cortices.