Failure hurts: the effects of stress due to difficult tasks and failure feedback on pain report.

Two experiments were conducted to investigate the effects of task difficulty and perceived success/failure on pain report. The first experiment found that difficult reading comprehension problems led to an increase in pain report. The second experiment found that task difficulty per se may not have accounted for the effects, but that perceived failure of the more difficult task led to increased pain report.

Exercise-induced analgesia: fact or artifact?

This study critically examines the reported exercise-induced analgesia effect in view of the potential stress-induced analgesia of pain testing itself. Two designs were used to test whether previous findings of analgesia were induced by the exercise procedures or by the stress of the pain testing procedures themselves used in such experiments. In the first design, post-test cold pressor pain ratings were obtained from college students following exercise (bicycle ergometry) and two control tasks (minimal exercise and non-exercise).