The Pulvinar Thalamic Nucleus of Non-Human Primates: Architectonic and Functional Subdivisions

The pulvinar, the largest nucleus of the primate thalamus, has extensive and reciprocal connections with several areas of the neocortex. These input-output loops suggest that the pulvinar may regulate the flow of information within and between cortical areas in a highly dynamic fashion. Therefore, understanding the anatomical subdivisions within the pulvinar, and its connectivity with the cortex, is paramount to understanding pulvinar physiological function. However, there is a stark contrast regarding the way that the pulvinar is subdivided depending on the technique employed. Cytoarchitectural and immunohistochemical methods reveal a very similar pattern of pulvinar subdivision across Old- and New-World monkeys. On the other hand, electrophysiological and connectivity studies expose clear discrepancies in pulvinar organization across primate evolution.