Display Patient Information Leaflets

Date issued: December 2024

For review: December 2026

Ref: A-627/DT/Neuropsychology/FND Understanding the diagnosis

PDF: Functional Neurological Disorder (FND) Understanding the diagnosis.pdf[pdf] 566KB

Understanding the diagnosis

Functional Neurological Disorder (FND) refers to problems in the functioning of the nervous system. FND results in unwanted symptoms due to problems with the messaging between the brain and body. For example, changes in movement, thinking skills, or loss of consciousness. These problems are not due to broken or damaged parts of the nervous system. Symptoms in FND can be called Functional Neurological Symptoms, or FNS. With treatment, FND symptoms can decrease, or even stop.

FND is surprisingly common. One study reports that roughly 1/3 of patients attending a neurology outpatient clinic experience functional symptoms. Even though it is common, it is not widely known about among patients and health professionals. Below are some common questions we are asked about FND.

What is FND?

FND is a condition that affects your brain and causes your body not to function as it should. Your brain receives millions of messages from the nerves around your body every day. That is a lot of information! Sometimes our brains can’t cope with processing all of these messages, and people can experience very real neurological symptoms, without there being any damage to the nervous system.

One helpful way to understand this is to think of the brain like a computer:

A computer has hardware, like the cable work and hard drives. It also has software that allows it to process information. 

The hardware and the software both need to be working well in order to function normally. 

FND is like a glitch in the software part of the brain, leading to very real symptoms that impact on people’s daily lives.

Ask the experts: what is FND?

“FND is a set of symptoms that affect each person differently, these symptoms may change in intensity and regularity, this is frustrating, scary and sometimes downright annoying. It seems that just as you get used to one set of symptoms, another symptom comes along to fool you. FND takes time to accept, acknowledge and to learn to live with. Accept all the help you can get, don’t worry about what people think, they are not you and they are not going through what you are going through. Reach out to others who are also affected, remembering that each person’s symptoms will be different, as unique as you are. Contact the charities, join the online meetings/local meet ups. Meeting someone with the same condition, somehow validates you, gives you someone to ask all those questions, that come to you when no one is around (or like me, in the middle of the night)”

FND Advocate, living with FND in Plymouth, UK (with permission)

What are the symptoms of FND?

Every function that is controlled by the brain can be affected. Different people are affected by different symptoms.

Symptoms vary from person to person, but may include problems with: 

Movement

• Difficulty moving parts of your body as normal.

Thinking skills

• Difficulty with thinking skills such as brain fog, attention, memory, speech, and fatigue.

Sensation

• Experiencing pain or changes in how you touch, see or smell things.

Awareness

• Changes in awareness or vacant episodes.  These can look like epileptic seizures but are not due to abnormal electrical activity in the brain. They are sometimes called non-epileptic seizures or functional seizures.

What causes FND?

People with FND experience changes in the messaging signals of the nervous systems for many reasons. There are usually several factors, although they are not always clear, that typically result in the body being in a hypervigilant state.

Biological, environmental and psychological factors can play a role in the development of FND.  For example:

• A physical illness or injury

• Pain or headaches

• Emotion or physical “burn out”

• Mood and mental health e.g. high levels of anxiety

• The impact of difficult life events

• The impact of challenging social circumstances, e.g. relationships, housing, finances

Of these factors there are some that can make the brain more vulnerable to symptoms, and some that can trigger episodes of symptoms. Sometimes these factors overlap and can have a domino effect on each other. Some people do not have a clear trigger but still experience functional symptoms. 

It is important to remember that FND symptoms are real and not your fault.

What is the treatment for FND?

It is possible to retrain the brain to improve how it functions.

For some people the brain retrains itself without extra support. Others can learn to retrain their brain using techniques and strategies. Some people need more support or therapy.

If there are other factors that worsen your symptoms (such as anxiety, depression, pain, or headache) then treating these as well as possible can benefit your symptoms. For some people, this can resolve their symptoms. If people have problems with movement, then physiotherapy can help. If there are psychological factors, then psychological therapy can be helpful.

The first step is understanding the diagnosis well and learning what different factors can impact on your symptoms. 

Often these can be environmental (certain situations or stimuli like loud noises or bright lights), psychological (like difficulties with mood, relationships, or emotions), or things that affect your essential needs (like lack of sleep, dehydration, poor nutrition, or having a cold or other illness).

The next steps in treatment aim to focus on improving your symptoms by getting into healthy routines and using strategies that help your body to function well.

How long will FND affect me?

It is typical for symptoms to fluctuate over time and each person will have a different journey with FND, so this is a very difficult question to answer! 

We know that with appropriate support and/or self-management many people’s symptoms improve back to a normal level of functioning. For some people, symptoms may get worse before they get better. For others, symptoms are more chronic, but by making adjustments they can enjoy life in a way that means FND does not impact on them as severely.

How can I learn more

We have mentioned that the first step to improving symptoms is to have a good understanding of your FND. After reading this information you may want to learn more by doing one of the following:

• Explore FND on your smartphone. MyFND is a mobile phone based app that contains information about FND and strategies you can use to help manage your symptoms. Find out more about myFND app. 

• Read about FND. Find detailed information about specific symptoms of FND and ways to manage symptoms at Functional Neurological Disorder Guide

• Reach out to an FND charity. Visit FND Hope UK or Go to FND Friends

• Summarise what you know. Write down what you understand about FND or practice explaining FND to someone you trust.

What if I develop new symptoms?

Symptoms of FND in themselves are not dangerous or life threatening. This means that if you have been given a diagnosis of FND after appropriate input from a Neurologist, and the symptoms are the same but worse, you probably don’t need to call an ambulance (unless you are not able to look after yourself at home). 

Remember, FND is not protective against other disorders or diseases. If you develop new symptoms, you should see a medical professional to assess whether those are due to FND, or something different.

What are the next steps?

Because there is no damaged part of the nervous system, there is the potential for things to improve. You have the power to re-train your brain. Different things help for different people at different stages of their journey with FND. At each stage, focus on what you can do. 

After reading this booklet, ask yourself the question, what can I do next to help manage my symptoms?