Endorsement and memory bias of self‐referential pain stimuli in depressed pain patients

Abstract
This study investigates information processing in chronic pain patients by comparing the responses of depressed pain patients, non-depressed pain patients and non-pain control subjects. Each subject contributed two scores: endorsement of adjectives as descriptors of themselves and their best-friends; and free recall of the presented words. The stimuli consisted of depression-related, pain-related and neutral control adjectives, and each content category was split into negative and positive valence. The four-way interaction between group, reference, content and valence was significant both in the recall data and the endorsement data. Further analysis revealed that depressed pain patients exhibited a bias towards self-referential negative pain words, but not towards self-referential negative depression information. These results are interpreted in line with content specificity theory of information processing and have implications for targeting cognitive interventions with pain patients.