Neurofilament architecture of superior and mesial premotor cortex in the human brain.

Monoclonal antibody (SMI-32) to neurofilament protein was used in an immunochemical study of the premotor cortex of two human brains in comparison with other architectonic techniques such as Nissi, myelin, cytochrome-oxidase and acetylcholinesterase staining in order to distinguish cortical subdivisions. SMI-32 immunoreactivity technique provides 'neurofilament architecture' patterns specific to area 4, caudal area 6 (area 6c) and rostral area 6 (area 6r). Particularly, the distinction between the two subdivisions of area 6, which is difficult to appreciate with the usual cytochemical or enzyme architectonic techniques, appears very apparent with this technique. Hence, it was possible to localize the topographic boundaries of area 6a alpha and 6a beta of the Vogts on the dorso-lateral convexity and the supplementary motor area and the presupplementary motor area on the mexial wall of the hemisphere.