What is Functional Neurological Disorder (FND)?

It can be difficult to explain in simple terms what is Functional Neurological Disorder (FND)

I like to imagine that our body is a sophisticated computer. It is running countless programs each day, sending signals, and processes commands seamlessly. The important part, now if you imagine that suddenly without any warning, the software gets a ‘Bug’.

All the hardware is working perfectly fine – the wires are intact, the chips are functioning correctly – however the signals are not being received or sent correctly. This can lead to unpredictable, sometimes debilitating, and often scary malfunctions.

This analogy ‘software glitch’ is, I find one of the simplest ways to begin understanding Functional Neurological Disorder.

So if you have been struggling with mysterious symptoms that doctors find difficult to explain, or maybe you have just received an FND Diagnosis, then you’re not alone.

The first step in managing FND is to understand its symptoms and, importantly, what do they mean.

What does the ‘Functional’ in FND, really mean?

The word ‘functional’ in FND, does not imply that your symptoms are imaginary, or that they are ‘All in your head’. In fact, it is quite the inverse! It refers to an issue with the functioning of your nervous system.

Your brain, spinal cord, and the nerves are structurally normal, but the signals that are sent between them get disrupted, leading to very real, involuntary symptoms.

You can think of it like this:

• Structural problem (eg, stroke): Damage to the brain’s ‘hardware’ (eg, a broken wire)
• Functional problem (FND): A bug in the brain’s software (eg, a program not running correctly), even though the hardware is intact.

This is an important distinction because it means that your symptoms are not something that you are consciously doing or can simply ‘snap out of’. They are genuine, neurologically-based issues.

What are the symptoms of FND

The number of symptoms that a person with Functional Neurological Disorder (FND) experiences can vary widely and greatly from one individual to another.

Some people may have only a few symptoms that affect them, while others might experience a much larger and more complex range of symptoms.

In addition to the primary symptoms directly associated with FND, individuals often also experience other related symptoms such as persistent pain and ongoing tiredness, which can significantly impact their overall quality of life and daily functioning.

Common Symptoms of FND

Motor Symptoms

• Weakness or paralysis of limbs
• Tremors or shaking
• Abnormal gait or difficulty walking
• Dystonia (involuntary muscle contractions)
• Jerky or inconsistent movements

Sensory Symptoms

• Numbness or tingling sensations
• Loss of sensation in certain body parts
• Visual disturbances such as double vision or blindness without an organic cause

Seizure-like Episodes

• Nonepileptic seizures or psychogenic non-epileptic seizures (PNES)
• Episodes that resemble epileptic seizures but have no abnormal electrical brain activity

Speech and Voice Problems

• Slurred speech or difficulty speaking
• Voice changes or loss of voice

Cognitive and Psychological Symptoms

• Memory problems
• Concentration difficulties
• Anxiety, depression, or other mood disturbances

Other Symptoms

• Fatigue
• Dizziness or unsteadiness
• Pain without clear neurological cause

The Good News: FND is Treatable

When I was diagnosed with FND, one of the first things the neurologist said to me was ‘You can recover from FND’ and there are treatments available to you.

If like me recovery seems impossible when the doctor tells you that you have FND, don’t give up hope, because I have experienced recovery from my motor and cognitive symptoms.

You can read many patients stories on neurosymptoms.org