Mental activity causing physical PEM, specific symptom patterns?

Snow Leopard

Snow Leopard

Senior Member (Voting Rights)
As found in a previous poll, there is a divergence of experiences of PEM as triggered (if at all) by cognitively triggered PEM.

"Some aspects feel fundamentally the same, but others feel different."

https://www.s4me.info/threads/poll-physical-vs-cognitive-pem-same-or-different.16948/

This is a fresh thread to specifically discuss for those that experience it, whether there is a distinct and specific overall pattern of symptoms (and time frame) of PEM for those who experience physical PEM as a result of mental exertion. Noting differences from that of physical activity triggered PEM.

Note that while we mentally exert we may also have other stressors on our body such as sitting in the same position for a long time (or strain our eyes from reading) so ideally if we can remove that from our examination somehow...

I am particularly interested in people's experiences of autonomic symptoms/POTS/OI (report exacerbations on standing for example) as well as any flu-like malaise, eg sore throats etc. Are these symptoms heightened or not? What I want is specific detail on the symptom patterns and time frames, not whether they are simply the same as those from physical PEM.
 
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For me, completely the same, unseperable.

They felt different when I was mild, but thinking back that’s only because physical activity would cause much worse PEM.

Now that I’m very severe, and most my PEM is cognitive. There is absolutely no difference in presentation. (I don’t think there ever was for me, just the illusion when I was mild because I could overexert physically to much higher levels than I could cognitively).

As for your second question, both flu like and autonomic symptoms worsen after both kinds of PEM.
 
I'm always on the cusp of a sore throat at any one time, it comes and goes like the weather. With cognitive activity it tends to stack if i do a lot over a period like multiple days, and seems to increase the odds of that sore throat seesawing into a full flu feeling and into PEM.

A relative of mine used to work as a teacher, and would work ridiculously hard in the weeks leading up to half term break, then when his break started would come down with a brutal cold like clockwork. I always kind of related what was happening to me with cognitive exertion a bit like that. High stress period followed by illness.
 
For me the thing that changes the most is the underlying trend of how good or bad I am. Then physical or mental triggers are a layer on top of that. Along with all the other changes we have in exactly which set of symptoms or their intensity/duration.

I would say there are some differences in mental and physical PEM, but they’re different flavours of the same thing if that makes sense? It may be the case that the worse I am the more similar they are as others seem to be saying.

Honestly I find it very difficult to clearly answer these questions. There are so many variables involved. Sorry that’s probably not a great deal of help…
 
Two instances of fairly short lived PEM earlier this year that I have some notes from. One from physical activity (sitting up and moving around to cut my hair) another from cognitive/sensory (a very loud and chatty visitor). Both followed similar patterns of aching, more fatigue, feeling ill or general rough and a bit throaty and a bit more OI (although not too bad as it’s okay atm, but being upright was less pleasant). These developed over a period of 12-24 hours then persisted along with worse sleep for maybe 4 days before improving. The sensory/noise one had more sensory/noise sensitivity to start with. Maybe the physical one tended more towards the ill feeling earlier. Can’t be sure this is entirely indicative of all my PEM periods!
 
I don't know if I get cognitive PEM because all my cognitive work takes place using a laptop. What I thought was cognitive PEM turned out to be screen intolerance and has nothing to do with cognitive activity.

The only difference to physical PEM is that I get dizzy (not OI dizziness, but eyes having trouble to follow head movements kind of dizziness. Perhaps like a concussion, except I never had one) and if I keep pushing, this turns into PEM. PEM onset is characterised by body chills, a runny nose, headache, nausea, and calf pain, but all of this only lasts a couple of hours. The next day I have a big headache and feel a bit hungover which I guess is true PEM. I don't feel fatigued at all.

Maybe another difference is that I used to be out of breath from sitting up when I was in physical PEM even though I don't have OI. I've managed to avoid physical PEM for a few months though and I don't know if this symptom still occurs.
 
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I’ve only experienced cognitive PEM a few times, early on in my illness when I was trying to force myself to stay in college. It took a lot more to trigger it—a few back to back days of studying for several hours with little sleep in between, whereas physical PEM could be triggered after a short walk. In this early stage, physical PEM actually felt more like a simple delayed “worsening of symptoms,” whereas the cognitive PEM resembled flu-like malaise more. That might have been because the cognitive PEM was “building” over time as I continued to push myself and eventually triggered a more severe response.

It’s possible I’m retroactively misremembering details since I didn’t even know I had ME/CFS at this point and only later realized that the flu-like symptoms were probably PEM and not frequent colds.

Now I’m mild and never get cognitive PEM, only a headache and brain fog if I try to use my brain for too many hours in a row, which is not delayed and usually resolves overnight
 
I don't know whether I get cognitive PEM. It might be there, but it could only be distinguished from physical PEM if I was able to get complete rest. I'm not set up to do that; I'm up to the limit of my physical capacity every day, and because the limit isn't consistent, I often stray over it.

I do have rapid cognitive fatiguability, though, and it's worse than my physical fatiguability. My current project, learning to read music, feels like training with heavy weights in a gym: quick progression to failure and the "muscle" can't be used again until enough time has elapsed.

If I try again, failure is more rapid, I might not manage the same weight, and persisting will make me feel nauseous. Currently I'm at five minutes of trying to discern meaning from a picture of a flock of starlings on telegraph wires before the brain freeze happens.
 
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Creekside said:
Isn't looking at a screen a cognitive activity? It's not muscular (aside from eye muscles). There's a lot of information processing going on in looking at a screen.
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Fair enough. I thought it was a sensory issue, but then again I'm not light sensitive so it's definitely the screen that messes with my brain. Almost like a concussion that doesn't heal maybe?

What I meant is I don't think I have issues learning new skills or processing new information as long as it doesn't require screen time.
 
My PEM from cognitive activity used to be identical as from physical.

However I think things have changed a bit more recently, with the advent of massive awful headaches at back of my skull with more severe light senstivity, after too much cognitive, that arent present after physical. Thats a change after 20 odd yrs of illness. I've been on a downward trajectory for a while now.
 
Subjectively I would report both cognitive and physical exertion triggering a similar pattern of PEM, though I can not be certain I am not misinterpreting my experiences.

Generally I feel more confident about my subjective accounts when I am able to predict accurately, as in with my gluten intolerance I can predict if I eat such and such that twenty four hours later I will experience these symptoms. However with either physical and cognitive exertion it is harder to isolate specific components in the real world, cognitive exertion generally comes with some physical action and sensory stimulation, just as physical exertion has associated cognitive and sensory demands.
 
I agree it is a bit difficult to separate out physical/orthostatic from cognitive exertion. I’ve definitely had numerous occasions of PEM from working at home. This involved sitting for 5 hours,with short breaks, at my table working on laptop and dialling into meetings, audio as 10 years ago video meetings weren’t the norm. There was a lot of cognitive effort going on but also sitting up feet on the floor. At the time I had much less awareness of orthostatic intolerance and mainly related that to standing in queues.

So in retrospect the factors causing PEM were
concentrating on writing and reading written material for long chunks of time, concentrating on absorbing what was going on in teleconferences which could be 2 hours long with multiple people, so somewhat bombarding with both factual information and reading human behaviour of colleagues.
Alongside keeping myself upright for 5 hours.

I would have an immediate reaction and need to lie on the sofa for an hour when my work day finished. I felt physically and cognitively drained to the extent of barely able to do anything, cognitively vacant. along with the bad flu type symptoms and swollen glands I have had at times I would say this is when I was worst affected by ME symptoms.

I worked alternate days and would be in bed with PEM on non work days.
 
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JemPD said:
doesnt that happen after PEM tiggered by a physical overdo as well though? it does for me
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Definitely—but it's also instant.

I can stand and walk for a minute or two, but I can't form coherent sentences while I'm doing it. However if I'm able to collapse back into my wheelie, I regain the ability to make sense after a few minutes' rest.

It's like that old joke about being so stupid you can't walk and chew gum at the same time. Literally true. :rofl:
 
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