Somatic symptom and related disorders
Functional Neurological Symptom Disorder (FND)
Functional neurological disorder causes involuntary motor, sensory or episodic symptoms—such as weakness, tremor, seizures or gait difficulty—that are real and can be significantly disabling.
A positive neurological diagnosis
FND is not diagnosed merely because tests are normal or another disease has not been found. A neurologist identifies positive signs of internal inconsistency or characteristic variability that show a problem in how nervous-system networks function rather than necessarily visible structural damage.
Functional symptoms and another neurological condition can coexist. Psychological stress is not required for the diagnosis, and the absence of an identified stressor does not rule it out.
Possible symptoms
- Limb weakness, gait difficulty, tremor, jerks, dystonic posture or episodes of falling.
- Functional seizures, altered sensation, vision or hearing, and speech, voice or swallowing difficulty.
- Pain, fatigue, cognitive fog and sleep problems may coexist and add to disability. First seizures and new neurological symptoms still require medical assessment.
Treatment and rehabilitation
Clear explanation of the positive diagnostic signs and the involuntary nature of symptoms is an important first step. Specialist physiotherapy retrains movement and attention through gradual functional goals.
Occupational, speech or swallowing therapy may be added. Psychological treatment can help with functional seizures, movement fear, stress or co-occurring trauma without implying that the symptoms are imagined. Medicines target specific co-occurring conditions rather than FND itself.
When urgent help is needed
Do not automatically attribute every new symptom to an established FND diagnosis. Sudden one-sided weakness, new speech or vision difficulty, a first or prolonged seizure, serious injury, prolonged loss of consciousness or breathing difficulty needs emergency medical assessment.