Autonomic measures and behavioral indices of pain sensitivity.

Autonomic measures (skin conductance and heart rate) were obtained from subjects before (warning period), during (immersion period), and after (resting state) the performance of the Cold Pressor task under tolerance instructions. The Autonomic Perception Questionnaire was administered shortly before the Cold Pressor task. Skin conductance and heart rate during the warning period proved to be significant predictors of pain tolerance behaviorally measured. The Autonomic Perception Questionnaire did not reveal any relationship between awareness of autonomic arousal and pain tolerance nor between actual level of arousal and subjective awareness of this arousal.