The intraspinal branching patterns of fast and slow pyramidal tract neurons in the cat.

Antidromic activation of single pyramidal tract neurons (PTNS) was obtained in cats by stimulating either the dorso-lateral funiculus with ball-electrodes, or the spinal gray matter with microelectrodes. The results indicate that the distribution area of single PTNS is much wider than the area of a single motor nucleus, suggesting that single PTNS may influence different motor nuclei.