Heart-rate reactivity to cold pressor stress following biofeedback training.

Three previous studies have shown that biofeedback training is useful in modifying heart-rate and pain ratings during ice water stimulation (cold pressor test). Subjects were given an initial cold pressor followed by heart-rate biofeedback training and a final cold pressor test in which they were instructed to control their heart rate in accordance with the prior training. It was assumed that a heart-rate control skill had been learned. In the present study, two groups of subjects (N = 9 each) were given either increase or decrease heart-rate biofeedback training following the same procedures as previously, but subjects were not instructed to control their heart rate during the final cold pressor test. Heart rate, skin conductance, electromyographic activity, and respiration were measured. The biofeedback training effects replicate the previous results. However, no heart-rate or pain rating differences were found between the two groups during the final cold pressor test. Thus, previous findings cannot be accounted for simply by a shift in heart rate and/or pain reactivity following training itself. The findings suggest that a biofeedback strategy may be useful in modifying physiological and subjective responses to painful stimuli but only if it can be used as an active coping skill.