Electrophysiological evidence for the presence of fibers in continuity between dorsal and ventral roots in the cat.

Action potentials were recorded from the L7 or S1 dorsal root of the cat following stimulation of the peripheral end of the cut ventral root of the same segment. Conversely, action potentials were also recorded from the ventral root while stimulating the peripheral end of the cut dorsal root. Based on the conduction velocities of 52 single fibers, one-third were A delta-fibers and the remaining two-thirds belonged to the C-fiber category. These results suggest that there are both A- and C-fibers in continuity between the dorsal and the ventral root.