The book The Body Keeps the Score held up in front of the camera. Georgina is sitting in the background listening to music.

Functional Neurological Disorder: The Common Neurological Condition You’ve Never Heard Of

If Functional Neurological Disorder is so common then why have I never heard of it?

You may not have heard of FND, but Functional Neurological Disorder goes by many names, including:

  • Functional Movement Disorder (FMD)
  • Non-Epileptic Attack Disorder (NEAD)
  • Functional Neurological Symptoms (FNS)
  • Functional Neurological Symptom Disorder
  • Non-Epileptic Seizures (NES)
  • Psychogenic Seizures
  • Psychogenic Non-Epileptic Seizures (PNES)
  • Dissociative Seizures
  • Conversion Disorder

Many of these are outdated, such as Conversion Disorder and Psychogenic Seizures / Psychogenic Non-Epileptic Seizures. Functional Neurological Disorder is the new, updated name for conversion disorder. Psychogenic Seizures / Psychogenic Non-Epileptic Seizures (PNES) are now called Non-Epileptic Attack Disorder (NEAD).

If you’re looking for some specific information about FND, you can skip to:

What Is Functional Neurological Disorder?

FND is a neurological condition that affects the functioning of the brain (hence ‘functional’). There’s a problem with the way the brain and body communicate, so they give each other mixed messages. It’s a bit like playing Chinese Whispers.

Medical professionals often explain FND as a software-hardware problem. Imagine your brain as a computer (hardware) and your nerves as software. The hardware isn’t broken so should function correctly, but there’s a problem with the software so it doesn’t. This is why FND doesn’t show up on any scans. There isn’t a structural problem with the brain such as a tumour, but its wiring is faulty and that’s why FND patients experience symptoms.

FND has been explained to me by a paramedic like a car’s engine management system being faulty. In this case, if you try and switch on the indicators, the brake light will come on (or something similar). I find this to be a better example than the hardware-software example that’s often used. It’s easier to understand, especially if the person you’re explaining FND to drives or knows anything about cars.

You can find out more about explaining Functional Neurological Disorder in my video above (check out this post for the transcript) and my post What Is FND? that I made for FND Awareness Month.


Patients with Functional Neurological Disorder have real, debilitating symptoms that are beyond their control.

Symptoms of Functional Neurological Disorder vary greatly from patient to patient. They can affect any part of the body and are very unpredictable.

Motor Symptoms

  • Paralysis
  • Weakness
  • Swallowing problems
  • Gastrointestinal problems
  • Tremors
  • Spasms
  • Bladder/urinary problems
  • Falls
  • Balance problems
  • Gait problems

Mental and Cognitive Symptoms

  • Fatigue
  • Concentration problems
  • Headaches
  • Migraines
  • Insomnia (and other sleep problems)

Sensory Symptoms

  • Speech problems
  • Loss of vision
  • Double vision
  • Pain
  • Tingling
  • Numbness
  • Reduced sensation
  • Hypersensitivities (e.g. hyperaware of touch, hypersensitive hearing)
  • Speech problems (e.g. foreign accent syndrome and aphasia)
  • Visual disturbances

Altered Awareness Symptoms

Due to the array of symptoms, patients are often misdiagnosed with conditions like epilepsy, multiple sclerosis and Parkinson’s.

FND can affect anyone at any age, although it’s fairly uncommon in children. Studies suggest FND is more prevalent in women than men, although affect both men and women equally in people over 50.

What Causes FND?

When FND was first recognised as a condition, it was called “hysteria”. Since then, it’s always been viewed as a psychological condition. It was thought past experiences and trauma were presenting themselves (or ‘converting’ themselves, hence the term ‘conversion disorder’) as physical symptoms. Only recently has it started being recognised as a neurological or neuropsychological condition, although the psychological history still reflects itself in some of FNDs synonyms like Conversion Disorder and Psychogenic Non-Epileptic Seizures (PNES).

Can FND Co-Exist with Other Conditions?

A common misconception of FND is that it can’t co-exist with other neurological conditions, or even any other condition, but it’s actually common for it to co-exist alongside other diagnoses. I have 12 other diagnoses alongside FND, so let’s just say it’s definitely possible!

It’s common for patients to experience anxiety and/or depression alongside FND. Sometimes these develop due to FND and the things patients experience as a result of that, but this isn’t always the case. Some patients may have anxiety and/or depression before developing FND later in life.

I have both anxiety and depression which has developed as a result of FND and the trauma I experienced after getting ‘sick’. Unfortunately this is common in patients with FND, possibly due to the stigma around it.

Chronic pain is also common in patients with FND. A related disorder is fibromyalgia, which is another condition presenting with nervous system dysfunction.

Something I’ve noticed (but hasn’t been researched) is that Ehlers-Danlos Syndrome and other hypermobility disorders seem to be common in people with FND – far too common for it to be a coincidence. I often wonder if I’d have FND if I didn’t have EDS?

Tests for Functional Neurological Disorder

There are no diagnostic tests for FND, so a diagnosis is usually made upon elimination of other causes. Some common tests FND patients undergo are:

  • MRIs
  • CT scans
  • EEG
  • ECG/EKG (if they experience non-epileptic seizures)

These scans will usually come up clear if the patient has FND (unless they also have another condition that shows up such as epilepsy). There are a few ‘positive signs’ that can aid in a diagnosis of FND:

Hoover Test / Hoover’s Sign

In a patient with functional limb weakness/paralysis, they are unable to push down on the bed when asked. However, when they try to push up against something with the other leg, they are able to push down with the weak leg.

A: a patient with functional weakness trying to push down against physician's hand with no effect.B: the same patient pushing up on the physician's hand with their unaffected leg is then able to push down with their weak leg.
This photo by Unknown Author is licensed under CC BY-SA.

Collapsing Weakness

Collapsing weakness is where a patient is asked to move the affected limb and finds it collapses. They may find this gets worse the more they try. This is often interpreted as the patient not trying, but this is something that is out of their control.

Diagnosing Non-Epileptic Seizures

Non-Epileptic Attack Disorder (NEAD) is the updated name for seizures caused by FND. Non-epileptic seizures can present similar to epileptic seizures, so some patients are misdiagnosed with epilepsy, sometimes for years, before finding out they actually have Non-Epileptic Attack Disorder.

Some medical professionals who are aware of FND are able to diagnose non-epileptic seizures and differentiate them from epileptic seizures (this is why I didn’t have an EEG to aid in my diagnosis). Many patients who suffer from non-epileptic seizures will have an EEG to rule out epilepsy, especially if their seizures are similar to epileptic ones.

Non-epileptic seizures have some typical features which include:

  • Eyes remain closed
  • Violent limb thrashing
  • Side-to-side head movements
  • Episodes that last longer than five minutes
  • Hyperventilation
  • Shaking attacks
  • Tearfulness upon recovery

Patients who are diagnosed with epilepsy are often put on anticonvulsants (epileptic medication). These rarely work in patients who have non-epileptic seizures, so this is another way FND patients could be diagnosed with Non-Epileptic Attack Disorder.

Note: It is possible to have both epileptic and non-epileptic seizures.

FND Treatments

Treatment for FND can be hard to come by for patients. It’s not just that treatment is hard to get, it’s that there really isn’t proper treatment, just like there isn’t a proper understanding of or proper testing for FND. As no one knows why Functional Neurological Disorder happens or what it really is, no one knows exactly how to treat it.

Most treatment revolves around cognitive behavioural therapy, or CBT. This works in some patients, but not all. Physiotherapy and Occupational Therapy should, and usually does, also play a part in treatment FND. These three therapies together are a type of multidisciplinary treatment that can be affective in patients with Functional Neurological Disorder. These are also the most common treatments for FND patients, but it’s not always offered to them, whether due to the doctor not knowing about it, or if it’s not felt to be appropriate for a specific patient.

Understanding FND

One of the main challenges for FND patients is the lack of understanding and the misinformation spread amongst medical communities. Understanding FND can help patients better treat the condition.


There’s no one medication to treat FND. Patients may be offered antidepressants (such as citalopram and sertraline) and neuropathic painkillers (such as amitriptyline, nortriptyline and duloxetine). Every patient reacts differently to each medication, so they usually have to try out different medications before they find which, if any, help them.


Cognitive Behavioural Therapy (CBT) is usually the first line of treatment for Functional Neurological Disorder. This is beneficial in some patients but not all.

Many patients wonder why they need to see a psychiatrist if FND is a neurological, not a psychiatric / psychological one, but it:

  • Can help patients understand and come to terms with their diagnosis.
  • Allows the patient to talk about behaviours and thoughts that are getting in the way of recovery/management.
  • Can help patients recognise symptoms of anxiety and depression (which are common in patients with FND).
  • Can help patients deal with the stress that comes with having FND.

Physical and Occupational Therapies

Physiotherapy and occupational therapy from professionals who understand FND can be beneficial to patients with motor symptoms such as gait problems and paralysis. It can also help patients who have decreased strength and stamina due to the condition. Physio for FND often focuses on ‘retraining’ the brain so the brain and body communicate better.

Physiotherapy for patients with FND differs from physiotherapy for other conditions. In patients with stroke, for example, are told to focus on moving the affected body part, but this tends to make functional symptoms worse.

Occupational therapy is a type of therapy that focuses on helping patients find adaptations and confidence to carry out ‘normal’ daily activities such as showering or cooking. Patients who see occupational therapists often see physiotherapists too.

Speech and Language Therapy

Speech therapy is an important part of treatment for patients suffering from functional speech symptoms. It can also help in patients who have trouble swallowing (dysphagia).

Other Resources

You can check out my Functional Neurological Disorder resources page for a full list, but here are some other FND resources that you may find helpful:


The majority of this information comes from my own experience as an FND patient, but I’m not a medical professional and I can’t know everything about FND so did some research for this post. I read up on FND on a few websites: National Organisation for Rare Disorders, and FND Hope.