Columnar cortico-cortical interconnections within the visual system of the squirrel and macaque monkeys

摘要: Cortico-cortical interconnections within the visual cortex of squirrel monkeys (Saimiri sciureus) were studied by means single or multiple injections [3H]leucine combined and horseradish peroxidase into dorsolateral striate prestriate cortices. Injections also made a Macaca speciosa for comparison. The results indicated that in Saimiri is precisely reciprocally connected with peristriate cortex, posterior bank superior temporal sulcus, including middle area (MT). MT area, but does not project to perstriate as case macaque. At each target site, radioactively labelled terminal fields are distributed distinctly columnar fashion, columns (120–480 μm diameter, commonly 240 μm) interdigitating sparsely unlabelled lesser widths. HRP-labelled neurons invariably exist columns. For all cortical areas examined except 17, lamina IV principal ‘receptive’ layer associational fibers, while layers III II, well V VI same column, receive progressively less input. As fibers from terminate mainly I, laminae III, receiving decreasing amounts present indicate major interconnected precise, topographical reciprocal fashion. arrangement found be basis both extra- intercortical connections.