Evaluation of Exposure Instructions to Pain: Should Therapist Focus on Fear Reduction or Expectation Violation?

Exposure elements are highly effective for the treatment of individuals with chronic pain and elevated fear-avoidance. However, different therapeutic instructions are justified by competing theories regarding underlying mechanisms. The habituation model suggests that therapists should focus on fear reduction. The inhibitory learning approach suggests that therapists should aim for maximal expectation violation. We employed a mixed 3 x 2 experimental design with the between-group factor instruction (habituation, expectation violation, control) and the within-group factor time (pretest, posttest) to provide a fine-grained analysis of both instructions. Nociceptive thermal pain was induced to female students (N = 112). Both instructions improved cognitive pain coping. Only the expectation violation instruction increased pain tolerance. Similarly, only the expectation violation instructions led to specific psychophysiological changes, characterized by a significantly higher initial increase and subsequent decrease in the skin conductance level. This study provides experimental evidence for the effectiveness of exposure-based interventions among individuals confronting acute thermal pain. Instructions addressing expectation violations appeared to produce the greatest effects. Testing concrete expectancies might further improve exposure effects. Future research needs to translate our findings into clinical practice.