Functional Neurological Disorder: 5 Warning Signs of the Little-Known Condition That Can Be Misunderstood

Functional Neurological Disorder (FND) can affect movement, speech, sensation and awareness, yet people living with the condition may struggle to have their symptoms understood. Experts are calling for better awareness, clearer diagnoses and more compassionate care.

A little-known neurological condition is drawing renewed attention after research highlighted how some patients feel dismissed or misunderstood when seeking medical help.

Functional Neurological Disorder, commonly known as FND, affects the way the brain and nervous system function. People with the condition can experience significant physical and cognitive symptoms, even when routine investigations do not reveal structural damage that explains them.

According to findings from researchers at the University of Cambridge and the University of East Anglia, disagreements about diagnosis, limited clinical training and stigma can contribute to difficulties for people living with FND.

The research, published in Rheumatology International, examined international survey responses from 1,853 patients, 400 clinicians and 463 members of the public, alongside interviews with patients and healthcare professionals.

The findings highlighted concerns about how the condition is diagnosed and explained. Only 30 per cent of surveyed participants agreed with an FND diagnosis, while just seven per cent agreed with describing symptoms as psychosomatic.

Researchers say the findings underline the importance of listening to patients, explaining diagnoses carefully and recognising that neurological symptoms can have complicated causes.

What Is Functional Neurological Disorder?

FND is a condition in which the brain's networks do not function as they should, affecting the way signals are processed and communicated throughout the body.

It can affect movement, sensation, speech, balance and awareness. Symptoms may vary considerably between individuals, and some people experience substantial difficulties with everyday activities.

Importantly, FND symptoms are real. They are not deliberately produced, imagined or necessarily under a person's conscious control.

Although the brain's structure may appear normal on routine scans, that does not mean its functioning is unaffected.

FND can sometimes resemble other neurological conditions, including epilepsy, Parkinson's disease and multiple sclerosis. However, the mechanisms involved are different, and a qualified healthcare professional must assess symptoms to establish an appropriate diagnosis.

The exact causes of FND are not fully understood. For some people, symptoms may begin following an illness, physical injury, migraine, surgery or a period of significant stress. However, there is no single trigger that explains every case, and psychological stress is not a requirement for developing the disorder.

Five Important Signs of Functional Neurological Disorder

Recognising possible symptoms is an important first step towards seeking appropriate medical assessment. The following are five key symptom groups associated with FND.

1. Weakness in the Arms or Legs

One of the recognised symptoms of FND is weakness affecting an arm, leg or several limbs.

A person may struggle to lift an arm, grip objects, stand comfortably or move a leg as expected. In some cases, the weakness can resemble symptoms associated with a stroke or another neurological condition.

The severity can vary, and symptoms may interfere with walking, working, dressing or completing ordinary daily tasks.

Sudden weakness, particularly when accompanied by facial drooping or difficulty speaking, requires emergency assessment because it may indicate a stroke or another serious medical problem.

2. Temporary Paralysis or Difficulty Moving

Some people with FND experience episodes in which a part of the body becomes temporarily difficult or impossible to move.

These symptoms can be frightening and may significantly affect independence. Movement difficulties can fluctuate, with some people experiencing periods of improvement followed by a return of symptoms.

Although paralysis can occur in FND, it should never automatically be attributed to the disorder without appropriate medical assessment.

New or sudden paralysis requires urgent medical attention to identify or exclude potentially serious causes.

3. Seizure-Like Episodes

FND can cause functional seizures, sometimes called dissociative seizures or functional non-epileptic seizures.

These episodes may involve shaking, unusual movements, staring, reduced responsiveness or suddenly becoming motionless.

Although they can resemble epileptic seizures, functional seizures are different from seizures caused by epilepsy. Both conditions require appropriate assessment, as their treatments differ.

Witnessing an episode can be distressing for family members and friends, particularly when they do not understand what is happening.

Anyone experiencing a first seizure-like episode should receive urgent medical assessment. Emergency help is particularly important if an episode lasts five minutes or longer, repeated episodes occur without recovery, breathing is affected or a serious injury occurs.

4. Problems With Walking, Balance or Coordination

Walking difficulties are another recognised feature of FND.

Some people develop an unusual walking pattern, experience unsteadiness or find that one leg drags when they move. Others may struggle with balance or make movements that feel difficult to control.

These problems can increase the risk of falls and make everyday activities more challenging.

In some cases, symptoms fluctuate depending on the situation or type of movement being attempted.

Specialist physiotherapy may help people develop safer movement patterns and improve their ability to carry out daily activities.

5. Speech, Memory and Concentration Difficulties

FND can also affect communication and cognitive functioning.

Possible symptoms include slurred speech, developing a stutter, difficulty finding words, problems concentrating and memory difficulties.

Some people may experience changes in their ability to express themselves, while others struggle to process information or maintain focus.

These symptoms can be particularly frustrating when they interfere with employment, education, relationships or social activities.

However, speech difficulties and sudden confusion can also indicate serious medical conditions. Sudden changes should never be assumed to be FND without prompt assessment.

Why Are Experts Calling for Better Awareness?

The research highlights how the way a diagnosis is communicated can influence a patient's experience of treatment.

Some people with FND report feeling that their symptoms are dismissed or attributed to psychological causes without adequate explanation.

Neurologist Professor Guy Leschziner has highlighted how outdated ideas associated with the condition's historical terminology continue to influence public understanding.

Experts increasingly recognise that FND cannot simply be explained as a psychological response to stress. Its causes and contributing factors are complex, and experiences differ between individuals.

Researchers say clinicians should explain their reasoning clearly, acknowledge uncertainty where it exists and ensure patients understand the diagnosis and available treatment options.

A diagnosis should not prevent further investigation if symptoms change or new concerns arise.

Can Functional Neurological Disorder Be Treated?

Although FND can be disabling, treatment and rehabilitation may help people manage symptoms and improve their quality of life.

Treatment is usually tailored to the individual's symptoms and needs. Depending on the circumstances, it may include:

• Specialist physiotherapy: Helps people practise movement and develop more effective movement patterns.
• Occupational therapy: Supports independence and helps people manage everyday activities.
• Psychological support: May help with symptom management, coping strategies and associated difficulties when appropriate.
• Education about FND: Understanding how the condition affects brain functioning can help patients participate in treatment.
• Multidisciplinary care: Coordination between relevant healthcare professionals can support a more comprehensive approach.

Recovery varies. Some people improve substantially, while others experience persistent or recurring symptoms. Early access to appropriate care may be beneficial, although individual outcomes cannot be guaranteed.

When Should You Seek Medical Advice?

Anyone experiencing unexplained weakness, movement difficulties, seizure-like episodes, speech changes or persistent cognitive symptoms should seek medical assessment.

These symptoms can have several possible causes, and recognising them does not establish an FND diagnosis.

Call emergency services if symptoms develop suddenly and suggest a stroke, if someone has a prolonged or repeated seizure-like episode without recovering, or if there are other signs of a serious medical emergency.

Most importantly, people experiencing neurological symptoms deserve to be listened to and assessed with care.

Greater awareness of FND, better communication and appropriate access to treatment could help reduce stigma and improve support for those affected.

Disclaimer: This article is intended for general informational and educational purposes only. It is not a substitute for professional medical advice, diagnosis or treatment. The symptoms described may be associated with several medical conditions and do not confirm FND. Always consult a qualified healthcare professional about health concerns. Seek emergency medical assistance for sudden or severe neurological symptoms. Do not delay or disregard professional medical advice based on information in this article.