Figure 9. Effect of reducing temperature on the development of the ‘notch’, recorded from sensory axons (A) and motor axons (B, C and D).

Skin temperatures (°C) are indicated in the legends for each subject. The depolarizing conditioning current was set to +40% of the threshold for the test potential for the sensory recording and +60% for all three motor recordings. A (sensory) and B (motor) were recorded from the same subject on separate occasions. Cooling the limb increased the latency, amplitude and duration of the notch, but decreased S2, the accommodative response attributed to activation of slow K⁺ channels.