FND - Functional Neurological Disorder  

A functional disorder means that there is an inability or failure of the brain to send and receive signals properly. Click here for information on the website of NIH.


There may be motor, sensory and/or cognitive symptoms that are inconsistent with other conditions.

In 2018, the World Health Organization, WHO, accepted a new description of diseases. There have been changes that mean that (temporary) complaints of pain and (temporary) motor disorders are now recognized as a symptom of FND, provided they cannot be explained by another clinical picture.

The International Classification of Diseases (ICD 11) succeeded the previous WHO classification. FND is recognized as a neurological disease. 


With FND there is no damage to the brain, but the nervous system does not function as it should.
There are several misunderstood conditions within neurology that have significant consequences for people, but for which science does not yet have an answer as to the cause. Where in the brain does something go wrong? Is it the ''software'' or the ''hardware''? Are the complaints caused by emotions? Are there other factors?
Everything in the brain is so closely connected that it can take a long time before all questions are answered. There is still a lot to research in the medical world.


People with FND are as likely to report physical limitations, emotional problems and reduced health-related quality of life as people with other neurological conditions.

Scans are inconclusive except in some situations a functional MRI (fMRI). The table of structural MRI studies in functional neurological disorders showed, among other things, reduced pituitary volumes. (Atmaca et al., 2016; Yildirim et al., 2012)



The symptoms can be very diverse and usually there is a combination of symptoms such as:

  • walking disorders
  • weakness in limbs
  • epilepsy-like seizures, psychogenic nonepileptic seizures (PNEA), seizures, blackouts
  • tremors (tremors and jerking movements)
  • paralysis
  • numbness in the skin, sensations in the feeling
  • altered sensation in the arm, leg or face on one side of the body (hemisensory syndrome)
  • facial spasms
  • headache
  • hearing less well
  • Intermittent vision loss, blurring, blurred vision, double vision
  • fatigue
  • sleep problems
  • cognitive problems
  • chronic pain, to a greater or lesser extent



People with FND often mention triggering circumstances such as an accident, flu, illness, illness that required staying in bed for some time, migraine or migraine-like headache attack, anesthesia, intense emotions, after dissociation or panic attacks.

Provoking causes cannot always be found.
Multidisciplinary treatment options by, among others, well-trained physiotherapists, pain therapists and/or psychologists can sometimes reduce some of the complaints.


More information:

FND society

FND Hope


A video about FND:



a PDF for download:


FND Functional Neurological Disorders Neuropsychiatric Associations With PDF 1 Pdf
PDF – 496,7 KB 17 downloads











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