Abstract: Thresholds and conduction velocities of ortho- and anti-dromic responses were measured in dorsal column postsynaptic(DCPS)neurons in the cat in terms of unitary recordings,Along train of afterdischarges with long latency was shown in part of DCPS neurons in addition to a short train of initial discharges with short latency;no correlation was seen in thresholds or conducticn velocities between the ortho-and anti- dromic responses;and the thresholds in antidromic responses were significantly higher than those in orthodromic ones,although the conduction velocities in ortho- and anti-dromic responses were close, ranging in A-beta fibers,The results indicate that A-delta and/or C fibers involved in the presynaptc fibers of DCPS neurons;no matching exists between the pre-and post-synaptic fibers with A-beta size in the neurons;and the neurons' postsynaptic fibers drop hastily in size upon their termination.

Key words: afferent neurons, dorsal column postsynaptic neurons, pre-and postsynaptic fibers