Functional neurological symptoms occur commonly in healthy adults: implications for the pathophysiology of FND 2026 Palmer et al

[Andy]

Abstract

Objectives:
Functional neurological symptoms which do not meet clinical definitions of functional neurological disorder (FND) are common in clinical practice. Understanding the distinction between these ‘benign’ functional symptoms and FND is crucial in defining FND as an entity for study, and as a clinical syndrome. We aimed to measure the frequency of functional symptoms in people who do not have FND.

Methods:
A survey was administered to 95 clinicians who attended an international conference on FND. Participants were asked to report the occurrence and characteristics of experiences with features of functional sensory or motor symptoms, or dissociation, which they had experienced at any time.

Results:
Of the 95 people who responded to the survey, 57.4% reported having experienced any functional symptoms, and 47.9% reported having experienced functional motor or sensory symptoms. The symptoms reported were generally short-lived and caused only mild distress and disruption. Most respondents who reported having experienced a functional symptom reported having had multiple events through their lives.

Interpretation:
The results suggest that the lifetime occurrence of functional neurological symptoms is at least two orders of magnitude higher than the prevalence of FND. The high prevalence of functional symptoms in people who have never had FND challenges the common assumption that the occurrence of functional neurological symptoms is synonymous with FND. We propose that FND is better conceived of as a failure of the mechanisms by which functional neurological symptoms resolve, rather than the occurrence of functional symptoms per se. This reconceptualization implies new research directions for the underlying aetiology of FND.

Open access

 

[rvallee]

And what are "functional symptoms", you might not care to ask but have to for miserable reasons?

Functional symptoms are neurological symptoms which are generated by abnormal brain processing.6 They are distinctive in their striking and paradoxical variation in
intensity with symptom-focused attention or effort to overcome the symptom. Typically, greater levels of symptom-focused attention are associated with increases in
symptom-severity, and direction of selective attention elsewhere causes reduction or complete remission of the symptom.7,8 Functional symptoms encompassing almost all categories of neurological symptoms are seen, including abnormalities of movement, sensation (both somatosensation and the special senses), consciousness, and cognition.9

Anything you want. By this definition, hunger would count as a "functional" symptom, as would sleepiness, nausea and anything you can think of that involves senses in some way. Noticeable that this definition is entirely circular, because how is this "abnormal brain processing" defined? By having "functional" symptoms, of course!

The mysticism, it spreads, it just keeps spreading, to parts known and unknown.

 

[Utsikt]

We propose that FND is better conceived of as a failure of the mechanisms by which functional neurological symptoms resolve, rather than the occurrence of functional symptoms per se. This reconceptualization implies new research directions for the underlying aetiology of FND.

They’ve finally figured out that disease = the cause of the symptoms doesn’t go away. How groundbreaking.

 

[SNT Gatchaman]

The social and economic situations of healthcare professionals attending an international conference are likely to be favorable compared with those of many people, and it could reasonably be expected that the proportion of them affected by neurodevelopmental and mental health conditions known to be associated with FND might differ from that of the general population.

So only the poors then?

(Also if you look at the world's most extreme rich and powerful men, now and through history, I don't think you can reasonably claim no neurodevelopmental and mental health conditions.)

Likewise, it is possible that some of the participants might have had their interest in FND stimulated by their experience of relevant symptoms, or that their expertise in FND might cause them to over-interpret symptoms as having commonalities with functional symptoms. Conversely, perhaps some individuals experienced symptoms that were elicited by their exposure to people with FND. We cannot rule out possible biases introduced by these factors, however unlikely they might seem.

Yep, that'll be it, defo.

 

[rvallee]

They’ve finally figured out that disease = the cause of the symptoms doesn’t go away. How groundbreaking.

I don't know, this looks a lot like "another turtle down" to me. "The mechanisms" is still this nebulous concept that can be shaped into any form they want it to fit into.

 

[Sean]

Yep, just another reframing to keep the gravy train rolling along. Coz the old reframing is wearing out, as non-explanations tend to do with repeat exposure to reality.

 

[bobbler]

They’ve finally figured out that disease = the cause of the symptoms doesn’t go away. How groundbreaking.

maybe but if @rvallee comment about what might get chucked into this box of what these symptoms are is only defined by the vairation in 'intention/focus' then one big thing we need to be checking is the wording of questions and severity of thing being reported

'the yips' is common in the sports world whether just friendly play or training properly - for example suddenly finding that as a golfer you go to do an easy putt and at the point of hitting it your hand does something silly or a swing that was perfectly fine suddenyl one day gets out of kilter and you can't correct it so are stuck with however many months of not being able to get back the drive off the tee that you used to be able to do. Tennis serve, gymnastics vault and so on all come under this same thing.

But it isn't of course necessarily at all the same thing as FND, a terrible illness. Noone with the yips who suddenly is suffering from their tennis serve no longer working is also finding that they have the symptoms that those with FND are reporting because they are quality of life and independence-level issues. Which could mean.... the most obvious conclusion of .. these just aren't the same thing and their 'theory' is disproven.

SO it seems there is room for rather propaganda-like to use theory-driven ideas of what someone thinks a condition might be then describe it badly to get laypersons to categorise things 'they think might fit this idea' and somehow link them.

PLus of course the issue that you can end up with a shaking arm as you try and get a drink to your mouth for completely different reasons, due to a different illness. Either on a fluctuating basis, particular pattern if it relates to exertion, exhaustion, flare, issue with whatever that condition relates to and it could be long-term or short term.

I really don't fully get what they are trying to do that could be genuine here.

This reminds me slightly of the research we see from time to time where they get a bunch of students to say they feel tired and call it some 'scale' of ME/CFS 'because it is fatigue'. And rather than looking for the fascinating difference - of how those students don't go on to suffer that getting worse and worse each time they try and push through and so over years end up with lower thresholds and more debilitated, but they weren't really that debilitated in the first place as a 'symptom burden' and thinking 'oh... penny-dropped, so that's the illness - it's that the 'manage your fatigue advice' makes you worse is when you have ME/CFS instead of being not a person with ME/CFS' they just think we aren't doing it right.

 

[MrMagoo]

So they discovered that being healthy is a risk factor for becoming ill?

 

[Sean]

Fits in with the research that shows being alive is a major risk factor for dying.

 

[MrMagoo]

Fits in with the research that shows being alive is a major risk factor for dying.

I hear it’s almost 100% but perhaps economic factors have some impact.

 

[Sean]

Obviously some psychosocial factors in there too. If you don't want to live strongly enough then you will die.

 

[MrMagoo]

Obviously some psychosocial factors in there too. If you don't want to live strongly enough then you will die.

Is it something that people hear about and that’s what influences them? If you have a lot of exposure, if people you know all die, then you’re influenced and go on to die yourself?