For comparison, studies were also made of flare on the inner forearm. Experiments were approved by the local ethical committee. Typical results are shown in Fig. Flare was readily detectable on the palmar skin of the hand, although there were several differences between hand and forearm. Grey scale expresses flux as a percentage of the level in skin areas outside the flare.
White circles indicate the position and size of the stimulating electrode.
The smaller flares presumably mean that C-nociceptor receptive fields are smaller, although some must still be quite extensive as flares up to 9 mm were seen.