Parameters of the static burst discharge of lingual cold receptors in the cat.

Thermal stimuli were applied to the upper surface of the tongue of the cat. The stimuli ranged from 40 degrees C to 10 degrees C and were changed in cold steps of 5 degrees C, each temperature lasting 2 min. Afferent impulses of single specific cold fibers from the lingual nerve were analysed by a computer program. About 90% of the fibers showed bursts under static conditions. The bursts began as doublets at the temperature of maximal average frequency. This temperature varied from 40 degrees C to 15 degrees C in different fibers, the average being 30 degrees C. The parameters burst period, burst duration, pause duration, intraburst interval and spikes per burst increased monotonically from 30 degrees C to 15 degrees C. The possible physiological significance of the burst pattern is discussed.