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Home / Causes / Why has it happened?

Why has it happened?

What could be the reasons that lead to the change in nervous system function described on the page describing ‘how does FND happen’?

The answer seems to be that there are many potential reasons why an individual can become vulnerable to FND. These reasons can be divided up in to:

These factors can be

This is called the “biopsyschosocial model of illness”. It doesn’t just apply to FND. All illness has a psychological and social dimension. Someone with multiple sclerosis who feels miserable or has a lot of debt will tend to experience worse symptoms than someone with multiple sclerosis who is not unhappy and has no other life stresses.

Our models of why people get FND are incomplete. Many of the factors that seem to be relevant are also relevant for lots of other symptoms.

Its still often unclear why someone with these vulnerabilities should for example, become weak down one side, or start to develop a tremor.

I have explained some ideas about why these individual symptoms might happen on the relevant pages (see weaknesssensory symptoms, seizures, movement disorder).

The picture below shows some factors which can be relevant in the development of functional symptoms. But when you look at this remember that people vary tremendously in how many of these factors are relevant. For some people, many factors are relevant. For others, only one or two are

It is especially important to state that:

YOU DO NOT HAVE TO BE STRESSED. DEPRESSED OR ANXIOUS TO DEVELOP FND

YOU DO NOT HAVE TO HAVE EXPERIENCED AN ADVERSE CHILDHOOD TO DEVELOP FND

A model of how various risk factors lead to and perpetuate FND – a disorder going on in the brain

Lets look at some of these things in more detail

Predisposing factors

We know from studies that people with FND are about 2-4 times more likely to have had adverse experiences in childhood or adult life like physical or sexual abuse. That still means most have not had these things. But how could that make someone more vulnerable to FND? It probably happens for a number of reasons

If you are someone who has had an adverse experience in the past, then you may get a hopeless feeling that the ‘damage has already been done’. This is not the case. Treatment can help look at these kinds of factors if they are present and help you to ‘retrain’ longstanding patterns of response. This can help you come to terms with whats happened but also manage ‘threats’ to your body more easily.

But other predisposing factors are just as important. Other common physical illnesses like migraine or joint hypermobility syndrome/Ehlers Danlos type 3 seem to make people more likely to get FND. In fact other medical conditions are one of the commonest risk factors for FND generally.

There is some evidence that people with FND are more likely to be obsessional, which makes them good workers, with a good attention to detail, but also not good of ‘letting go’ when an abnormal program gets lodged in their brains as part of FND. This can also link to a tendency to be ‘always on the go’. People who are ‘always on the go’ often are not good at being unwell when they have a minor illness or may not have recognised they were running themselves down. This is sometimes one reason why they collapse.

Precipitating or Triggering Factors

Throughout this site Ive discussed the kinds of triggering factors that can be important in FND. For example

Perpetuating Factors

These are all the things that once you become ill just keep making it worse for example

You may want to look at this table and decide what your own personal risk factors were and whether anything can be done about them. Read more about individual cases elsewhere.