The physical effect of pain can be alleviated by verbal reassurance from another person but only if they are someone we identify with. The new finding by Michael Platow and colleagues at the Australian National University demonstrates the significant role of social psychology in pain perception and could have important implications for placebo treatments.
Fifty-four science students held their hand in icy water for as long as they could, up to a limit of 130 seconds, imposed for ethical reasons. Then a confederate of the researchers appeared, posing as either a science or arts student who had done the experiment earlier. They told the participants that the second go at the ice bath was 'much easier'. A control group didn't receive any reassurance. The participants then held their hand in the icy water for a second time.
After reassurance from another student, the pain of the second ice bath provoked far less physical arousal in the participants (as measured by the sweatiness of their dry hand) than it had done the first time around, but only if that reassurance came from another science student, not if it came from an arts student. The control group didn't show any reduction in arousal.
The reassurance didn't have any effect on how long the students were able to hold their hands in the water for, but that is probably because so many of them were able to keep their hand in the water for the entire 130 second limit, even on the first exposure.
“Our research suggests that the relative success of verbal communications, such as placebo communications, is likely to obtain primarily, if not solely, when administered from in-group members,” the researchers said.
Platow, M.J., Voudouris, N.J., Coulson, M., Gilford, N., Jamieson, R., Najdovski, L., Papeleo, N., Pollard, N. & Terry, L. (2007). In-group reassurance in a pain setting produces lower levels of physiological arousal: Direct support for self-categorisation analysis of social influence. European Journal of Social Psychology, 37, 649-660.
Image credit: Wellcome Library, London.
BELL, Sir Charles (1774-1842) Sir C. Bell, the anatomy and philosophy of expression as connected with the fine arts. London: John Murray, 1844. Page 157 - pain.