SELF-REFERENTIAL SELECTIVE MEMORY IN PAIN PATIENTS

The effect of self-reference on recall bias for pain stimuli was compa red in chronic pain patients and controls. It was hypothesized that se lf-referential encoding would result in better recall of pain stimuli in chronic pain patients. In contrast, it was predicted that a non-pai n control group would display no recall bias for pain-associated stimu li, regardless of the encoding reference. Subjects were tested in two conditions. The first condition (self-referential) involved encoding a list of words constructed from sensory pain, affective and neutral wo rds. Elaboration at the encoding stage was achieved by asking subjects to imagine themselves in situations involving these words. Subjects w ere also asked to rate the likelihood of these situations occurring on a scale of 1 to 5 (from 1 = 'will not happen' to 5 = 'certain to happ en'). The second condition (other-person reference) repeated this task in reference to another person with a matched list of words. A 2 x 2 x 3 factorial analysis of variance based on group x reference (self an d other) x word type (sensory, affective and neutral) was carried out on recall scores, with the likelihood ratings as a covariate. Results reveal a significant three-way interaction. The analysis indicated tha t, while pain patients show an increase in recall of sensory words and a decrease in recall of neutral words when these are encoded in refer ence to themselves, control subjects show no difference in recall of t hese word types regardless of the encoding condition. The results supp ort the notion that pain patients selectively recall more pain-associa ted words in comparison with other word types. However, this effect is only true for stimuli encoded in reference to themselves. It is propo sed that this processing bias may contribute to the maintenance of a s ense of helplessness and exacerbate the emotional impact of the pain e xperience.