Normalization of aberrant resting state functional connectivity in fibromyalgia patients following a three month physical exercise therapy

Abstract

Physical exercise is one of the most efficient interventions to mitigate chronic pain symptoms in fibromyalgia (FM). However, little is known about the neurophysiological mechanisms mediating these effects. In this study we investigated resting-state connectivity using functional magnetic resonance imaging (fMRI) before and after a 15 week standardized exercise program supervised by physical therapists. Our aim was to gain an understanding of how physical exercise influences previously shown aberrant patterns of intrinsic brain activity in FM. Fourteen FM patients and eleven healthy controls successfully completed the physical exercise treatment. We investigated post- versus pre-treatment changes of brain connectivity, as well as changes in clinical symptoms in the patient group. FM patients reported improvements in symptom severity. Although several brain regions showed a treatment-related change in connectivity, only the connectivity between the right anterior insula and the left primary sensorimotor area was significantly more affected by the physical exercise among the fibromyalgia patients compared to healthy controls. Our results suggest that previously observed aberrant intrinsic brain connectivity patterns in FM are partly normalized by the physical exercise therapy. However, none of the observed normalizations in intrinsic brain connectivity were significantly correlated with symptom changes. Further studies conducted in larger cohorts are warranted to investigate the precise relationship between improvements in fibromyalgia symptoms and changes in intrinsic brain activity.

Behavioral interventions in health neuroscience

“…Gutdirected hypnotherapy led to reduced pain system activity to pain stimulation for IBS patients, and exercise led to greater connectivity between nociception and pain regions for fibromyalgia patients, showing that behavioral interventions might alter how individuals respond to pain neurally. 80,83 In healthy adults without a chronic pain diagnosis, mindfulness training led to greater activity in cognitive control regions in response to pain stimulation, providing a foundation for future work exploring the effect of mindfulness interventions on chronic pain. 85 However, so far, this work has not linked changes in neural activity or connectivity with changes in chronic pain symptoms for patients, an important avenue for future research.…”

“…82 However, after the intervention, patients showed greater connectivity between the AI and primary sensorimotor areas, and this connectivity looked more similar to healthy controls. 83 This suggests that an exercise intervention can lead to stronger connectivity between pain and sensorimotor regions; however, these changes in neural connectivity were not associated with changes in symptoms. While it is currently unclear how changes in resting state connectivity in the pain system might be linked to changes in chronic pain symptoms, one possibility is that this increase in neural connectivity between a nociception region and a feedback loop may provide for more efficient regulation to decrease pain.…”

Is There Evidence for any Truly Effective Therapy in Fibromyalgia?

“…Pregabalin reduced connectivity between default mode network and other pain-related regions and significantly reduced grey matter volume within the posterior insula bilaterally, in comparison to placebo [22]. Following a 3-month exercise program, there was improvement in altered brain connectivity, particularly between the right anterior insula and the left primary sensorimotor area in FM patients [23]. Cognitive behavioral therapy was found to reduce nociceptive response in fibromyalgia subjects [24].…”

Promoting Physical Activity in Fibromyalgia

“…There is persuasive evidence that exercise induces positive changes in the brain areas associated with pain processing [10,11]. These findings raise the prospect that movement may be 'disease modifying' or at least affects key underlying physiologic perturbations.…”