Epilepsy and non-epileptic or dissociative seizures (FND?)

there was an episode of Diagnosis detectives on bbc last week:

The cardologist turns out to be wrong.
The neurologist explains that the seizures are either from epilepsy or 'dissasociative seizures'; interestingly they do conduct tests and manage to get results when the patient is actually having a seizure.
I can't find the right words at the moment but basically as there was no abnormal electrical activity going on in the brain the diagnosis was FND.

https://www.bbc.co.uk/iplayer/episode/m000mtqt/the-diagnosis-detectives-series-1-4-carys-and-andrew

 

I did not listen to the whole thing but I was impressed at the end of the section on 'Andrew' when the neurologist admitted that he did not know the answer. I did not hear the term FND used but maybe that was earlier?

I thought there was a contrast with Dr Barrett who seems to know the answer most times, for reasons that to me are far from convincing.

 

around 41:00 he explains the difference between epilepsy and functional neurological disorder.

eta:
an article describing the different kinds of seizures/convulsions
https://www.medicalnewstoday.com/articles/324330

eta2: in the film Unrest Jessica suffers a kind of seizure; it would be interesting to know what the explanation for that might be.

 

I missed that. But I was encouraged that his final words were more or less 'I don't know'.

I think it is reasonable to suggest that non-epileptic seizures originate from activity of those parts of the brain that are responsible for what we call 'mental' events. In fact epilepsy does too. I also think it is reasonable to have a category like 'FND' that implies that there is no structural damage causing abnormal nerve firing. But I would want to keep well away from any explanations that invoke 'stress' or 'emotion' for which we have no evidence base.

I also see no logic in using CBT unless the patient actually recognises that they are generating seizures through being stressed. As far as I know people don't recognise that- unless perhaps after it being suggested by a doctor!

 

In the case of Andrew though, I would ask why it took an accident/head trauma to trigger what they then say is caused by repressed emotional issues.

It's a bit like with ME starting with some kind of virus/infection being lost with the bps explanation.

 

I'm not up to speed with this, but would like to understand something. And the usual caveat: I have no medical knowledge.

Normal physical movement must presumably be initiated/controlled by some sort of electrical brain activity, and which must therefore be detectable. Are we saying this occurs in a different part of the brain to that which is seen with epilepsy?

With non-epileptic seizures there must presumably be some sort of electrical brain activity somewhere? Is it a similar signature as for normal physical movement?

If it is possible for muscles to spasm "independently" of the brain, without any brain signalling, then would clearly not be directly due to any mental activity. But I'm guessing that is not what we are talking about here. Or is it a possibility nonetheless?

 

Did anyone in the video implicate 'repressed emotions'? I certainly think that is bunk. But there needs to be a name for these non-epileptic seizures. FND would do for me if it did notary the baggage of BPS. If used by neurologist who admits we do not understand the mechanism I am not sure what to think.

 

During seizures EEG activity is likely to be distorted by electrical activity from muscles. But for true epilepsy there is widespread discharge well above normal levels. For non-epileptic seizures there will be activity but not over and above that expected from normal type brain activity plus muscle artefact.

In addition, people with epilepsy tend to have identifiable foci in cerebral cortex that give off bursts of activity even when not having seizures. These foci are thought to be where the widespread discharge starts.

Muscles can spasm independently of brain due to cramp (common enough) or tetany from low calcium but they rhythmic contractions seen in seizures need brain control. Rhythmic contraction may occur locally in spinal cord damage without brain involvement but not in all four limbs.

 

Thank you, that's really enlightening.

 

Functional neurological disorder is not a bad term if it means the functioning of the brain is damaged. Unfortunately, research papers into FND nowadays explicitly say that it is the new name for conversion disorder and hysteria. The term is now a meaningless euphemism for psychologically induced illness used simply to make it palatable to patients.

 

children can have febrile convulsions that are not epileptic seizures, so how does that tie in?

 

Hey I did that. Around age 2. And again around age 20. I have no idea if it's worth mentioning, I never did. Whenever I happen to actually have access to medical care anyway.

 

I forget these things but I think febrile convulsions are epileptic with widespread discharge. It is just that there is no persisting focus.

 

much fuller explanation here:
https://www.epilepsysociety.org.uk/non-epileptic-seizures

 

That looks a bit like the epilepsy society taking the opportunity to say that non-epileptic seizures are just what the psychiatrists say they are. The more I see of information put out by disease support groups the more it seems heavily laden with politics.

 

Just to play devil's advocate for a moment, re non-epileptic seizures.

Given the control signals (to and?) from the brain are identical to those seen in healthy people, then something is obviously going on that is undetectable by current medical technology. From this, how confident can we be that the "something undetectable" is not some low level, sub-conscious mental activity that has become "burnt in" somehow? What evidence do we have that it is not?

 

I don't think we have any evidence it is not. Butnthe key question is what we mean by 'subconscious mental'. If mental is conscious then there is none. If mental means all the processes that lead up to conscious events then how wide do we take that?

For me the key issue is that although it is clear that there are unconscious processes, capable of generating dreams for instance, I see no reason to think that we can have scientific discussions about how they work or how they might go wrong, since we know nothing about how they work and cannot find out. In particular I think it is wrong to describe such processes in terms of emotions, stresses, traumas, or desires in the way psychologists seem to think they are allowed to.

 

With all these "may"s and "might"s, at best, they are presenting a hypothesis. It needs to be proven before it can be used as the basis of treatments for a large number of people. They do not even consider how probable it is that the hypothesis is correct. Seizures may be caused because of demonic possession which was the theory for much longer than FND. Repressed memories came in with Freud and the psychoanalysts of the late 19th century, just a blip in time.

We know that people who experience a traumatic event can go on to develop post traumatic stress disorder. While it is unprovable how many people do so compared with ones who completely forget it, how many people forget they were in a train crash? Traumas seer themselves into memory.

And if traumas like that are not bad enough to forget why should something less be forgotten?

Things that were traumatic at the time are usually forgotten because people get over them, not because they repress them.

 

Yes, understood and agreed. Again playing devil's advocate.

Once we have learned to drive a car, many of our physical actions are what I would think of a subconscious (though I appreciate that may be mistaken terminology on my part). I don't have to consciously think about the specific physical actions, just think about the conscious-level needs - left-hand bend, speed up, slow down, etc - and the physical actions happen mostly unbidden at that level of thought. In effect the the low level functionality has become burnt into the subconscious somehow, via a learning experience.

So I can't help wondering if some powerful unwanted "learning experience" at some point in life, possibly inadvertent, could establish such a faulty subconscious, low level activity pattern. And if it were a deeply entrenched, very low level learned pattern, whether in fact it might be possible to unlearn (relearn might be a better word) it away.

 

One can wonder but for me this is just the sort of extrapolation from normal mental function to abnormal mental function that is illegitimate without understanding mechanisms. It is very like the way people extrapolate from normal immune function to abnormal, e.g. 'autoimmune' function when they do not understand the mechanisms involved. Now that we understand the mechanisms the old popular theories look ridiculous, and infac they always should have done.

The essence is that a set of rules about how something works does not give you a set of rules about how it does not work. The rules about going wrong are likely to turn out to be quite unrelated to the normal rules - including explaining why things don't go wrong most of the time.

I personally cannot see any helpful analogy between learning to drive and 'learning to have subconscious seizures'. The only people who entitled to create theories about making up seizures as a learning exercise would be those who do that sort of making up normally !! Which of course is a possibility.