Relationship of subjective helplessness and pain perception after electricskin stimuli

Objective and subjective controllability of painful stimuli are important f actors in pain perception. The present study investigated direct and indire ct effects of uncontrollability on perceived pain intensity in humans. Fort y-eight healthy male volunteers participated in a laboratory experiment usi ng a reaction time paradigm to induce controllable or uncontrollable feedba ck conditions in two randomly selected groups. Under controllable condition s, unpleasant electric skin shocks were applied, only when the actual time exceeded an individual threshold; under uncontrollable conditions, skin sho cks were applied randomly, using a yoked control design. Subjective helples sness, perceived pain intensity and additional psychological variables were assessed prior to and after the experiment. The results indicate a strong relationship only between the individually perceived helplessness and pain perception (r = +0.62, p < 0.0001) independent of objective stimulus contro llability. Neither mood states nor personality traits yielded a significant correlation with perceived pain. After uncontrollable shock exposure, subj ects described themselves as slightly more helpless and significantly more activated, anxious, and angry (p < 0.05). A path analysis revealed only a m odest indirect effect of objective uncontrollability on perceived pain inte nsity, and a strong independent impact of subjective helplessness. The resu lts underline the importance of subjective feelings of helplessness in pain perception, which should be taken into account in further studies. Copyrig ht (C) 2000 John Wiley & Sons, Ltd.