First somatosensory cortical columns and associated neuronal clusters of nucleus ventralis posterolateralis of the cat: an anatomical demonstration.

Abstract

Microlesions (30--275 microns in diameter) were placed in VPLm of the cat and the terminal axonal degeneration in SI cortex was stained using the Fink-Heimer I technique. Following each of these microlesions, small, localized patches or subcolumns of degeneration, relatively light in density, were observed within laminae IIIb and IV of SI when viewed in the coronal plane. In addition, a few degenerating fibers ascended to lamina I. These multiple subcolumns had distinct radial boundaries and were narrow in the mediolateral plane (80--120 microns in width) but elongated rostro-caudally (2500--3000 microns in length). Localized patches of degeneration were separated at their widest points by a..