Cherry BJ, Weiss J, Barakat BK, Rutledge DN, Jones CJ. Physical performance as a predictor of attention and processing speed in fibromyalgia. Objective To explore the associations between physical (both self-report and objective measures) and cognitive function for persons with fibromyalgia (FM). Design Correlational study. Setting An exercise testing laboratory in southern California. Participants Community-residing and functionally independent (not wheelchair-bound) adults meeting the American College of Rheumatology 1990 criteria for FM (N=51) with a mean age of 54 years and no history of stroke. Interventions Not applicable. Main Outcome Measures Composite Physical Function Scale, Fibromyalgia Impact Questionnaire, adapted Trail Making Test parts A (TMT-A) and B (TMT-B), Digit Symbol Substitution Test, a composite index of TMT-A, TMT-B, and Digit Symbol Substitution Test combined, and physical performance assessments. Results Hierarchical regression analyses indicated that better objective physical performance predicted increased cognitive function for TMT-A and the composite cognitive score after controlling for age and symptom burden. That is, as the physical performance level decreased, cognitive performance levels decreased. Conclusions Findings suggest that research is needed to determine whether patterns of physical activity participation, through their effects on physical fitness and performance, can enhance cognitive performance in persons with FM. Physiologic changes in specific brain regions in FM (eg, hippocampus, neural pain regions) suggest that further research is also warranted in determining specific relationships between biomarkers and cognitive performance in persons with FM.