The default mode network (DMN) has been proposed as a biomarker for several chronic pain conditions. Default mode network functional connectivity (FC) is typically examined during resting-state functional neuroimaging, in which participants are instructed to let thoughts wander. However, factors at the time of data collection (eg, negative mood) that might systematically impact pain perception and its brain activity, influencing the application of the DMN as a pain biomarker, are rarely reported. This study measured whether positive and negative moods altered DMN FC patterns in patients with chronic low back pain (CLBP), specifically focusing on negative mood because of its clinical relevance. Thirty-three participants (CLBP = 17) underwent resting-state functional magnetic resonance imaging scanning before and after sad and happy mood inductions, and rated levels of mood and pain intensity at the time of scanning. Two-way repeated-measures analysis of variances were conducted on resting-state functional connectivity data. Significant group (CLBP > healthy controls) × condition (sadness > baseline) interaction effects were identified in clusters spanning parietal operculum/postcentral gyrus, insular cortices, anterior cingulate cortex, frontal pole, and a portion of the cerebellum (PFDR < 0.05). However, only 1 significant cluster covering a portion of the cerebellum was identified examining a two-way repeated-measures analysis of variance for happiness > baseline (PFDR < 0.05). Overall, these findings suggest that DMN FC is affected by negative mood in individuals with and without CLBP. It is possible that DMN FC seen in patients with chronic pain is related to an affective dimension of pain, which is important to consider in future neuroimaging biomarker development and implementation.
Negative pain-related affect impacted default mode network functional connectivity magnetic resonance imaging in both healthy controls and chronic low back pain participants, which raises concerns for translation of the default mode network as a chronic pain biomarker.
Department of Clinical and Health Psychology, University of Florida, Gainesville, FL, USA
Corresponding author. Address: Department of Clinical and Health Psychology, University of Florida, 101 South Newell Drive, Rm 3151, P.O. Box 100165, Gainesville, FL 32610-9165, USA. Tel.: 325 273 5220; fax: 352 273 6156. E-mail address: firstname.lastname@example.org (M.E. Robinson).
Sponsorships or competing interests that may be relevant to content are disclosed at the end of this article.
Received January 29, 2016
Received in revised form August 22, 2016
Accepted August 24, 2016