Abstract
Evidence is accumulating regarding an association between autism and functional neurological disorder, a common cause for a wide range of neurological symptoms affecting motor, sensory and cognitive systems. Symptoms can include paralysis, tremors, sensory disturbance, vision loss and dizziness. Functional neurological disorder exists at the complex intersection of physical and mental health, neurology and psychiatry, and body and mind. Despite a recent resurgence in clinical and scientific interest, functional neurological disorder has lagged behind other causes of neurological symptoms in research, service development and acceptance. The nature of the association between autism and functional neurological disorder remains uncertain, but several plausible mechanisms can be identified from overlapping areas of research, highlighting endogenous factors such as atypical interoception, motor function, emotional processing and sensorimotor integration, alongside exogenous influences including adversity, healthcare inequality and stigma. This review first provides an overview of functional neurological disorder through various explanatory frameworks before applying biopsychosocial, neuropsychological and computational perspectives to conceptualise its intersection with autism. It then considers how this association might be understood and explores how services could be adapted to better recognise and support autistic individuals with functional neurological disorder across the diagnostic and treatment pathway.Lay AbstractFunctional neurological disorder causes real and often disabling symptoms, such as seizures, paralysis, tremors or sensory changes, even though standard medical tests do not show physical damage to the nervous system. Research suggests that autistic people are more likely to experience functional neurological disorder than their non-autistic peers, but the reasons for this are not yet understood. This article explores why autism and functional neurological disorder might occur together. It draws on research into how the brain processes body signals (like pain or movement), handles emotions and responds to uncertainty. It also looks at life experiences that affect health, including trauma, barriers to healthcare and stigma. This article shows that both internal factors (such as differences in movement, emotional awareness and sensory processing) and external factors (such as stress, inequality and misdiagnosis) may increase the chances of functional neurological disorder in some autistic individuals. Several models are introduced to help explain how these influences might interact. Finally, this article outlines how healthcare services could better support autistic people with functional neurological disorder. It encourages functional neurological disorder services to adapt communication styles, provide appropriate adjustments and include autistic voices in research and treatment planning to improve care and outcomes.