Discussion in 'ME/CFS research' started by Cheshire, May 20, 2019.
Sci hub, https://sci-hub.se/10.1007/s11682-019-00119-2
Selection criteria, "Canadian Criteria adapted for pediatrics (illness duration ≥3 months) (Jason et al. 2006)"
Funded by ME Research UK.
Trying to summarise the abstract for a news item, does this make sense?
Functional MRI showed similar changes after cognitive exertion in CFS patients and controls, suggesting similar effort and energy expenditure, but CFS patients were more fatigued and did less well on tests of speed and sustained attention and new learning. , suggesting lower starting energy threshold and cognitive resources.
Edited to remove authors speculative conclusions.
Perhaps tangentially supporting the glucose problem. If your glucose energy production system is screwed, would lack of starting energy not be a given ?
That tweet from Dr Mark Guthridge is a bit misleading, as cognitive exertion in the controls also resulted in reduced processing speed and attention - i.e. the same as with the young people with ME/CFS. It's just that the young people with ME/CFS were starting from a lower baseline.
This was interesting:
And this, where it seems likely that the young people with ME/CFS don't need advice on sleep hygiene to fix their sleep quality problems.
I have always felt uneasy about the term "subjective fatigue" in this sort of context. It seems to leave the way open to all sorts of misunderstanding. Presumably what it means is that the ME patients report greater levels of fatigue when there is no objectively measurable, or, at least, measured difference. It always seems to suggest the possibility that the reporting or the perception are faulty, and not the means of measurement. Perhaps it is too nice a distinction.
If I read it correctly, one good thing from this is the MRI confirms that the pwME were making just as much effort - as showed in the brain activity, but despite this their speed, sustained attention and memory were functioning less well on the tests. So it's not about not trying hard enough, being lazy, malingering etc. It seems to be about a reduced capacity, not reduced effort.
Sadly, I don't think their comments about effort and energy mean anything scientific. There is nothing about energy expenditure in the study as far as I am aware. I think their final statement in the abstract is hot air. The real finding of the study is that the ME patients' scans were normal - which is important.
Thanks, @Jonathan Edwards. I agree the last sentence seems to be speculation. I'll amend my news item.
Do you think there is any way of explaining the ME patients doing less well on the tests (speed, sustained attention etc), given that their brain scans indicated equivalent effort?
Only that they have ME and we don't know why that impairs thinking. I don't think the scan show effort. I am not sure anybody knows what they show other than pretty patterns.
Would it be a good idea to make an experiment with some brain blood flow enhancing intervention to see if it improves cognitive impairment?
Haven't they done studies with MRI's that showed a lack of blood flow for ppl with depression?
I think they measured fatigue with a visual analogue scale before and after the cognitive tasks. ME/CFS patients had more fatigue at each timepoint but the increase in fatigue following cognitive challenges was the same in controls. So the cognitive tasks did not increase fatigue more in the patients than in controls. I think this is what the term energy expenditure refers to.
Thats an interesting thought, but if I understood correctly the authors do not argue that the similar MRI scans are an indication of similar effort. Or did I miss something?
SPECT scans might be useful but they are frowned upon in my neck of the wood (medically speaking), probably because they show something amiss on a fairly reliable basis.
Probably me over interpreting the authors' interpretation:
I took that to mean they were seeing on the brain scans evidence of similar levels of effortful energy expenditure, ie trying just as hard.
Yes, you're probably correct - that sentence does seem to suggest something like that. Sorry. I was a bit confused by the term 'effort'.
If their MRI's aren't up to the task of demonstrating WHERE the cognitive deficits arise, then either the technology isn't up to snuff, or they haven't learned yet how to see and correctly interpret what it does show. We well know what blunt tools neurocognitive tests are, and how they routinely fail at capturing deficits withing our and similar communities. Brain imaging often isn't far removed from those, at least in terms of actually capturing - and demonstrating that concretely - what they hope/believe they are. Yet we are told that the problem is only a misplaced belief that there is a problem.
I cannot understand why patients pretend that neurologists and/or psychs, and the radiologists who they employ to read tea leaves, actually know what they are talking about even half of the time.
Write up from ME Research UK on this study
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