What is FND?

Functional Neurological Disorder (FND) can encompass a diverse range of neurological symptoms including limb weakness, paralysis, seizures, walking difficulties, spasms, twitching, sensory issues. 

Whilst the symptoms may appear similar to those seen in neurological diseases such as Multiple Sclerosis, Parkinson’s and Epilepsy, and can be just as debilitating, they are not caused by structural disease of the nervous system. Instead, they are caused by a problem with the “functioning” of the nervous system.

The structure of the body is intact, but there is a problem with how the nervous system is functioning, and how the brain fails to send and receive messages correctly. This impacts on how the body responds to different tasks such as movement control.

Functional Neurological Disorders are often explained to patients as a psychological reaction due to past trauma, or as symptoms due to stress. These explanations usually fail and result in patients feeling alienated, stigmatised and not-believed. The main reason for the failure of such explanations is that they take a potential risk factor and turn it into the cause of the problem.[1]

A diagnosis is made by a Neurologist from positive neurological signs and tests that are specific to Functional Neurological Disorders. The Hoovers Sign, for example, is a specific test in relation to limb weakness. It is important a positive diagnosis is reached to avoid misdiagnosis, and that consideration is given to the fact that FND may also present alongside other Neurological conditions.

Functional neurological symptoms are commonly seen in Neurology and Epilepsy clinics, and in pediatric care. Research suggests symptoms are the second most common reason for an initial Neurology appointment, after headache. Symptoms are sometimes referred to as Medically Unexplained Symptoms (MUS), which is inappropriate and misleading to those diagnosed and clinicians.

Current understanding is that biological, psychological and social factors may contribute towards a person’s vulnerability to developing a Functional Neurological Disorder. Research continues to ascertain a clearer picture of the causes and mechanisms.

To learn more about Functional Neurological Disorders please visit the neurosymptoms website which is a key information resource in the UK and worldwide, and is written by a leading specialist in this field.

CLICK HERE for information about symptoms.


[1]  Cock HR, Edwards MJ.  Functional neurological disorders: acute presentations and management Clin Med (Lond). 2018;18(5):414–417. doi:10.7861/clinmedicine.18-5-414