Neurophysiology of resilience in juvenile fibromyalgia.

Juvenile fibromyalgia (JFM) is a chronic pain syndrome predominantly affecting adolescent girls. Resilience may be a protective factor in coping with pain, reducing affective burden, and promoting positive outlooks. Brain regions affected in JFM overlap with those linked to resilience, particularly in the default-mode network (DMN). We investigate the role of resilience on core somatic and affective symptoms in JFM and assess the neurophysiological substrates for the first time. Forty-one girls with JFM and 40 pain-free adolescents completed a resting-state functional magnetic resonance imaging assessment and self-report questionnaires. We used clustering analyses to group JFM participants based on resilience, and principal component analyses to summarize core somatic and affective symptoms. We estimated whole-brain and within-DMN connectivity and assessed differences between higher and lower resilience JFM groups and compared their connectivity patterns to pain-free participants. The higher resilience JFM group had less affective (T = 4.03; P < 0.001) but similar core somatic symptoms (T = 1.05; P = 0.302) than the lower resilience JFM group. They had increased whole-brain (Ts > 4, false discovery rate cluster-level corrected P -value < 0.03) and within-DMN (T = 2.20, P = 0.03) connectivity strength, and higher connectivity between DMN nodes and self-referential and regulatory regions. Conversely, higher DMN-premotor connectivity was observed in the lower resilience group. Juvenile fibromyalgia participants with higher resilience were protected affectively but not in core somatic symptoms. Greater resilience was accompanied by higher signal integration within the DMN, a network central to internally oriented attention and flexible attention shifting. Crucially, the connectivity pattern in highly resilient patients resembled that of pain-free adolescents, which was not the case for the lower resilience group.