Functional Neurological Disorder (FND)

What Is Functional Neurological Disorder (FND)?

Functional Neurological Disorder (FND) is a real neurological condition in which the nervous system does not function properly, producing genuine physical symptoms that are often distressing and disabling.

It is sometimes described as a problem with the “software” of the brain rather than a structural “hardware” issue. Standard scans and tests (such as MRI or EEG) frequently appear normal or do not fully explain the symptoms, yet the effects on daily life are very real.

Common Symptoms

FND can present in many different ways. Some of the most frequently reported symptoms include:

  • Weakness or paralysis in limbs

  • Tremors, jerks or abnormal movements

  • Problems with walking or balance

  • Non-epileptic seizures (also called dissociative seizures)

  • Loss of sensation, numbness or tingling

  • Speech or swallowing difficulties

  • Visual or hearing disturbances

  • Fatigue, pain and cognitive difficulties (“brain fog”)

These symptoms can fluctuate and are often triggered or worsened by stress, fatigue or specific movements.

How Is FND Diagnosed?

Diagnosis is made by a neurologist based on a detailed history and specific clinical examination findings known as “positive signs”. These signs demonstrate that the nervous system is capable of normal function in certain situations, even if it does not work consistently in everyday life.

Tests such as blood work, scans and EEGs are often used to rule out other conditions, but the diagnosis of FND is positive rather than simply “tests are normal”.

Treatment and Management

Many people with FND can improve with the right support. Treatment is usually multidisciplinary and may include:

  • Specialist physiotherapy

  • Psychological therapies (such as cognitive behavioural therapy)

  • Occupational therapy

  • Speech and language therapy

  • Education and self-management strategies

Medication is sometimes used to help with associated symptoms such as pain, anxiety or sleep disturbance.

A Note from My Journey

In my own experience I was initially given a diagnosis of possible FND before later being diagnosed with Progressive Encephalomyelitis with Rigidity and Myoclonus (PERM), a rare autoimmune stiff-person-plus syndrome. My story is not intended to dismiss FND, which is a genuine condition that affects many people and can respond well to the right treatment.

Rather, it highlights how important it is for neurological symptoms to be thoroughly investigated when they are rapidly worsening, do not fit the typical pattern, or are accompanied by new physical changes. Getting the right diagnosis matters.

If you are living with FND, or if you feel your symptoms do not fully match the explanation you have been given, you are not alone. This website shares my personal journey with PERM while also aiming to support anyone navigating complex neurological symptoms.