Fear and anxiety's effects on pain-thresholds

Fear and anxiety: divergent effects on human pain thresholds
Rhudy, et. al.
Abstract
Animal studies suggest that fear inhibits pain whereas anxiety enhances it; however it is unclear whether these effects generalize to
humans. The present study examined the effects of experimentally induced fear and anxiety on radiant heat pain thresholds. Sixty male and
female human subjects were randomly assigned to 1 of 3 emotion induction conditions: (1) fear, induced by exposure to three brief shocks;
(2) anxiety, elicited by the threat of shock; (3) neutral, with no intervention. Pain thresholds were tested before and after emotion induction.
Results suggest that ®ndings from animal studies extend to humans: fear resulted in decreased pain reactivity, while anxiety led to increased
reactivity. Pain rating data indicated that participants used consistent subjective criteria to indicate pain thresholds. Both subjective and
physiological indicators (skin conductance level, heart rate) con®rmed that the treatment conditions produced the targeted emotional states.
These results support the view that emotional states modulate human pain reactivity. q2000 International Association for the Study of Pain.
Published by Elsevier Science B.V.
Pain 84 (2000) 65-72
PII: S0304-3959(99)00183-9
Categories: Fear,, Anxiety,, Stress-analgesia, Pain-threshold