Parameters calculated from the normalized time related response to local heat. A, normalized axon reflex response, t, time to the axon reflex response starting from the time that the local skin temperature was set to 40°C (arrow head, 9min. after start of local warming). The area under the curve (AUCheat) equals the maximum response to localized heating, with beginning and end of the time interval set to 0 and 40 min, respectively. Insert: the amplitude of the axon reflex (A) together with the time required to peak (t) are summarized as the area of a triangle. The time interval begins 9 min after start of localized warming, i.e. the time the heating device was set to 40°C.