abstract: An abundance of data has established the links between both pain-related cognitions and relationship attachment qualities in the experience of pain, including long-term functional health in chronic pain patients. However, relatively few studies have explored the dynamic relation between pain and pain-related cognitions within a day, and no studies have tested the moderating role of relationship attachment on the within-day cognition—pain association in chronic pain patients. The objectives of this study were to: 1) assess whether late morning pain flares predicted changes in afternoon positive and negative pain-related cognitive appraisals, and whether these changes in turn predicted end-of-day pain, and 2) explore whether adult attachment anxiety moderated the pain-cognition relation in individuals with chronic pain due to fibromyalgia. One hundred and seventy four partnered individuals with fibromyalgia completed initial assessments of demographics and attachment anxiety, and subsequently completed electronic assessments of pain intensity and positive and negative cognitive pain-related appraisals three times a day for three weeks. Multilevel structural equation modeling established that a latent negative cognitive appraisal factor (encompassing shared variance from catastrophizing, pain irritation, and self-criticism related to pain) mediated the link between late morning and end-of-day pain intensity, in line with the hypothesis. Analyses also provided some support for a mediating role for a positive cognitive appraisal factor (a composite of pain control, pain self-efficacy, and feeling pain without reacting) in the daily course of pain; the mediated effect for positive appraisals was weaker than the mediated effect of negative appraisals, but was sustained in a model that included negative appraisals. Inconsistent with prediction, attachment anxiety did not moderate the within-day links between pain and cognitions. These findings establish the dynamic links within day between pain and pain-related cognitions, and highlight the potential impact of both negative and positive cognitions on daily pain regulation. They point to the value of broadening cognitive-behavioral treatment strategies for chronic pain patients to target not only negative but also positive cognitions. / Dissertation/Thesis / Doctoral Dissertation Psychology 2015