The role of conditioning and verbal expectancy in the placebo response.

Both conditioning and expectancy models have been offered in recent years as explanations for the placebo response. Following our earlier work on conditioning placebo responses in human subjects the current study examined the relative contribution made by conditioning and verbal expectancy. Group 1 received a Combined Expectancy and Conditioning Manipulation; group 2 received Expectancy Alone; group 3, Conditioning Alone; and group 4 was the control group.

Conditioned response models of placebo phenomena: further support.

Following our earlier research, we further investigated a model that conceptualizes placebo phenomena as the result of conditioning and attempted to extend and replicate the finding that placebo responses can be conditioned in human subjects. Two groups of 10 subjects were told that they were receiving an analgesic which was in fact a placebo. During the conditioning, placebo administration was surreptitiously paired with an increase in the painful stimulus for half of the subjects and with a decrease for the other half.

The MMPI and psychological factors in chronic low back pain: a review.

The Minnesota Multiphasic Personality Inventory (MMPI) is widely used in the psychological assessment of patients with chronic low back pain (LBP). Patients' profiles have been used in a number of ways: in attempts to discriminate between cases; as predictors of both medical treatment and pain management program outcomes; and in attempts to assess degree of disability. Studies reviewed here indicate that the concept of psychological etiology of chronic LBP, despite widespread use, has failed to differentiate patients and to reliably predict response to specific treatment.