Suppression of pain-related thoughts and feelings during pain-induction: sex differences in delayed pain responses.

Women tend to report greater acute and chronic pain intensity than men, and various mechanisms have been proposed to account for these sex differences. Suppression has been related to amplified pain intensity, and thus we examined whether sex differences in the use of suppression partly explained the discrepancy between men and women on pain report. Participants (N = 222; women: 55%) underwent a cold pressor, during which half the sample was randomly assigned to suppress pain-related thoughts and feelings and the other half was not. A 2-min recovery period followed the cold pressor. Ten min later, all participants were exposed to another physical stimulus (a massage device). Significant condition x Sex interactions were found for pain intensity, sensory ratings from the McGill Pain Questionnaire and unpleasantness ratings for the massage device, such that: (a) men in the No Suppression condition reported lower pain and unpleasantness than women in the same condition; (b) men in Suppression condition reported greater pain and unpleasantness then men in No Suppression condition, but equivalent pain and unpleasantness to women in No Suppression condition; (c) differences between men and women on pain in No Suppression condition were partly mediated by women's report of greater spontaneous use of avoidance/suppression during the cold pressor. Results using an "addition" paradigm (i.e., manipulating use of suppression) and a "take away" (i.e., mediation) paradigm converge to suggest that women spontaneously use suppression to regulate pain more than men, and that the differential use of suppression partly explains the tendency for women to report greater pain intensity than men.