What is Functional Neurological Disorder (FND)?

This sheet is for people who have been told they may have FND, and for family or friends supporting them. It is general information from FND CONNECT CIC — not a diagnosis and not a substitute for clinical care.

In plain English

Functional Neurological Disorder (FND) is a genuine neurological condition. It means there is a problem with how the nervous system is functioning — how the brain and body send, receive and process signals — even when standard scans or routine tests may look normal.

A helpful analogy some clinicians use: the “hardware” of the nervous system may look intact, but the “software” (networks and signalling) is misfiring. That does not make symptoms imaginary.

Symptoms are real

FND can include weakness, paralysis, tremor, dystonia, gait problems, sensory changes (numbness, pain, altered vision or hearing), speech or swallowing difficulties, cognitive fog, blackouts, and functional (dissociative) seizures.

Symptoms often fluctuate. A better hour or “good day” does not mean unlimited capacity. Effort, stress, sleep loss, heat, illness and sensory load can all influence how symptoms show up.

Common myths — and the facts

Myths

“It’s all in your head” / attention-seeking
“Scans are normal so nothing is wrong”
“You could stop this if you tried harder”
“FND only happens to anxious people”

Facts

Symptoms are involuntary and real
Normal imaging does not rule FND out
Many people improve with the right rehab plan
FND can affect anyone; mental health can co-exist but is not the whole story

What often helps

A clear, respectful explanation that FND is real and that a plan exists
Multi-disciplinary rehab when available: physiotherapy, OT, psychology, speech therapy as needed
Pacing (steady activity, not boom-and-bust), sleep, and reducing threat/fear around symptoms
Work, school and home adjustments; peer support; tracking patterns for appointments

Safety first

If symptoms are new, sudden, severe, stroke-like, a first seizure, chest pain, or very different from your usual pattern, call 999 or use NHS 111. Do not assume it is “just FND”.