Effects of contingent versus yoked temperature feedback on voluntary temperature control and cold stress tolerance.

Twenty-four male internals (locus of control) and 24 externals were instructed to increase finger temperature under one of three conditions: (1) contingent feedback (CF), (2) yoked sham feedback (YF), or (3) no feedback (NF). Five 13-min training sessions were given. Feedback was then removed and subjects tested for voluntary temperature control. Finally, the cold pressor test, a laboratory analogue of natural cold stress, was administered under no-feedback conditions. Results demonstrated voluntary control of peripheral temperature following contingent feedback training, but not after yoked feedback temperature training. Contrary to expectation, the acquisition of voluntary control did not attenuate the stress response to thermal pain. Differences between internals and externals throughout the study were generally insignificant.