Functional neurological disorder, physical activity and exercise: What we know and what we can learn from comorbid disorders

Abstract

Functional neurological disorder (FND) is a common neurologic disorder associated with many comorbid symptoms including fatigue, pain, headache, and orthostasis. These concurrent symptoms lead patients to accumulate multiple diagnoses comorbid with FND, including fibromyalgia, chronic fatigue syndrome, postural orthostatic tachycardia syndrome, persistent post-concussive symptoms, and chronic pain. The role of physical activity and exercise has not been evaluated in FND populations, though has been studied in certain comorbid conditions. In this traditional narrative literature review, we highlight some existing literature on physical activity in FND, then look to comorbid disorders to highlight the therapeutic potential of physical activity. We then consider abnormalities in the autonomic nervous system (ANS) as a potential pathophysiological explanation for symptoms in FND and comorbid disorders and postulate how physical activity and exercise may provide benefit via autonomic regulation.

Keywords: Autonomic nervous system; Exercise; Functional neurological disorder; Physical activity; Psychogenic.

Fig. 1

Hypothetical Framework for the effect of physical activity, exercise, and sports on Functional Neurological Disorder (FND). In FND, there is suspected dysregulation of the autonomic nervous system (ANS). We propose that physical activity, exercise, and sports may be used therapeutically to alter ANS functioning, as can be measured through electrodermal activity (EDA), heart rate variability (HRV), Composite Autonomic Symptom Score (COMPASS-31), and via a variety of central nervous system (CNS) metrics.