Response variability to repeated mechanical stimulation of the skin in the dorsal column system

The response variability in the primary afferent fibers and in the post-synaptic neurons of- the cuneatus was determined using repetitive mechanical stimulation of the skin in cat. The response variability was larger in the post-synaptic neurons. Of the two studied mechanoreceptor types, the RA (rapidly adapting) units had significantly more variability at the cuneate level than the PC (Pacinian) units, but at the peripheral level no such difference was found. The results suggest that the PC units transmit signals more securely through the cuneatus than the RA units.