Laser emitted radiant heat for pain research.

Controlled radiant heat stimulation for a combined psychophysical and electrophysiological research in pain was achieved by the use of an infrared Laser beam. The computer controlled stimuli, being of very brief duration (down to 5 msec) and sharply localized, are suitable for recording of averaged evoked responses as well as for determination of pain and thermal thresholds. These stimuli can be applied to any locus on the skin. The threshold energy delivered by this technique is similar to that obtained by the Hardy-Wolff-Goodell method. Special precautions were taken to avoid injury to the skin and the eyes.