Table 1.

Effects of warm, noxious heat, cool, and cold counterstimuli on mean firing of VcTT neurons during baseline conditions

	Temperature, °C
	40°	45°	50°	25°	20°	15°	10°
Before	5.6 ± 1.1	5.5 ± 1.4	5.3 ± 1.2	5.1 ± 1.3	4.2 ± 1.4	4.8 ± 1.4	6.7 ± 2.0
During	6.5 ± 1.0	7.6 ± 1.4	10.2 ± 2.5	6.1 ± 1.4	7.5 ± 1.8	8.8 ± 2.3	11.7 ± 2.9
After	6.3 ± 1.3	6.2 ± 1.3	7.0 ± 1.9	5.1 ± 1.2	4.9 ± 1.3	5.0 ± 1.7	6.6 ± 2.1

Values are mean firing levels (in spikes/s) of trigeminothalamic tract (VcTT) neurons before, during, and after thermal counterstimuli. Note that none of the counterstimuli reduced firing levels following stimulation below those seen before application of counterstimuli.