SINGLE VERSUS REPETITIVE SPIKING TO THE CURRENT STIMULUS OF A-BETA MECHANOSENSITIVE NEURONS IN THE CROTALINE SNAKE TRIGEMINAL GANGLION

1. Intrasomal recordings of potentials produced by current stimulation in vivo were made from 24 (A-P) touch and 19 vibrotactile neurons in the trigeminal ganglion of 29 crotaline snakes, Trimeresurus flavoviri dis. 2. Usually touch neurons responded with a single action potential at the beginning of a prolonged depolarizing pulse, whereas all vibro tactile neurons responded with multiple spikes. 3. The electrophysiolo gical parameters examined were membrane potential, threshold current, input resistance and capacitance, time constant, rebound latency, and its threshold current. Touch neurons had higher input resistance (and lower input capacitance) than vibrotactile neurons. 4. In conclusion, current injection, which elicits a single or multiple spiking, seems a useful way to separate touch neurons from vibrotactile neurons withou t confirming the receptor response, and some membrane properties are a lso specific to the sensory modality.