Does Cognitively-induced PEM cause long crashes?

[Wishful]

I was having one of those imaginary conversations in my head (imaginary socializing doesn't seem to cause PEM), and I had an interesting question. I know cognitively-induced PEM has a different (shorter) time delay for many of us, but what about the duration of it? If, for example, people generally don't have long crashes from it, that might be a useful clue to what causes PEM.

I've included responses for physically-induced crashes too, since that puts things in better perspective.

 

[Mary]

My crashes generally last one day, whether from physical, emotional or cognitive exertion. And they all have the same delayed onset, about 24 hours. My crashes used to last 2 - 3 days before I started taking BCAAs about 10 years ago. And if stop them or get an inferior brand, I start to go downhill pretty quickly, back to my old state, within a week at the most.

I think PEM arises from our energy metabolism which is primarily anaerobic. I run out of energy quickly which is typical for anaerobic metabolism, and I think the achiness I get during a crash has to do with delayed clearance of lactic acid.

I wondered once why cognitive exertion causes PEM and then realized that the brain uses a lot of energy - according to this article, it uses 20% of the body's energy despite representing 2% of its weight. So if brain energy consumption was anaerobic as well, which seemed a strange concept to me (but why not?) then of course it would cause PEM after using it intensively.

I've read of people who will do an activity for, say, 15 minutes, but then will rest for 45 minutes and can get through the day that way without crashing the next. However, I can't make myself do that! But I'm thinking that 45 minutes of rest will let some of the lactic acid clear out instead of building up to high levels. I don't know - just an idea.

 

[hapl808]

For me, I don't think it's just that the brain uses too much energy - it's a different type. I can scroll through this forum and read and not crash. But if I sit down and try to edit a video, I feel more in a 'flow state' and that almost guarantees that an awful crash will follow.

It's by far my worst symptom, even though I cannot stand without assistance. If I could work on the computer or socialize without awful crashes, my life would be much more worth living.

 

[xploit316]

For me any of the following activities can cause Physical PEM which than has an effect on my cognition causing mood swings, anger irritability and delayed sleep issues.
1. Any activity which involves heavy lifting and exerting leg muscles. (Walking 30mins at slow pace in late evenings is fine)
2. Spending more than 30mins in high heat/humid environments
3. Playing video games, Chess, performing any mathematical calculations.
4. Eating high sugar, dairy and glutamate foods, fruit juices.
5. Being in noisy environments.

 

[southwestforests]

Unsure how to answer. In the couple decades I've had ME/CFS I've never tracked and recorded specific crash types, causes, duration.
Can say that cognitive effort wears me out. Sometimes quickly. Sometimes slowly.

Back in 2006 it was a big cognitive crash, I guess you could call it, which finally got me to the hospital to eventually be diagnosed with ME/CFS.


How do you divide out the crashes and causes anyway?

For instance;
Yesterday was our weekly meeting for creative writers group. We meet in a local baked goods and coffee shop which has a room with closeable glass doors in its 1800s downtown building.
I ran several errands on way to and on way home from.
Made 2 stops on way there.

A thing we often do at writers group is 25 minute timed writing to one or more of several provided prompts.
Yesterday I got about 2/3 a page dreamed up and typed out on this laptop & then my brain said, "That's it. I'm done with that. No energy left for creating from scratch."

Was that shortage of brain energy an effect of the mental activity?
Was that shortage of brain energy an effect of the physical activity.
Was it cause of what percentage of yesterday afternoon's and today's fatigue?

Was it merely one ingredient in a soup of causes and effects?

I don't know. I don know HOW to know.


Obviously I have enough mental energy to think this now. Physical energy is very low though.



Do know that the cognitive work involved in the annual renewal paperwork for state social services and for rental assistance wears me out and leave me drained.
Am unable to do either one in one day any more.

And right here right now I have run out of mental energy.

 

[Wishful]

There are other threads about the hows and whys of PEM. I was wondering if people got the weeks or months long crashes from purely cognitive exertion, such as chatting or filling out tedious paperwork. Plenty of people report such lengthy crashes from physical exertion, but does cognitive exertion have the same lengthy effect?

Am I misunderstanding "crashes"? I assumed that applied to severe PEM that lasted much longer than a couple of days. To me, PEM that lasts only 24 hrs is not a crash, it's just PEM.

 

[hapl808]

Am I misunderstanding "crashes"? I assumed that applied to severe PEM that lasted much longer than a couple of days. To me, PEM that lasts only 24 hrs is not a crash, it's just PEM.

To me, PEM and crash are close to synonymous. Although the way I use it is slightly different. More mild PEM is just every day for me, so I don't call it a crash. If I do too much, that leads to day(s) of being bedbound. I call that a crash - basically the difference between being housebound or bedbound.

I don't use 'crash' to mean PEM that last months. For me, any crash has the potential to eventually recover to baseline or not. For me, if a crash leads to a permanent lost off function or lasts months or years - that's just what I say.

I don't think I've had cognitive effort lead to permanent loss of function - but actually I have no way of knowing? A number of my permanent declines were more gradual, so likely different things were involved.

I've had long crashes (weeks or months) from heat, injury, etc. Don't think I had one more than a couple weeks from 'just' physical effort back when I had the ability to do physical stuff.

I also had a permanent decline from PEM triggered by an extended allergic exposure. Never recovered from that one.

 

[hapl808]

Also now I'm very limited physically, but my worst crashes were from videochats. They often lasted 1-2 weeks and had awful cardiac symptoms (blood pressure spikes, etc).

My physical crashes these days are usually just a few days - but since I'm housebound they're just triggered by cooking or things like that.

 

[L'engle]

There are other threads about the hows and whys of PEM. I was wondering if people got the weeks or months long crashes from purely cognitive exertion, such as chatting or filling out tedious paperwork. Plenty of people report such lengthy crashes from physical exertion, but does cognitive exertion have the same lengthy effect?

Am I misunderstanding "crashes"? I assumed that applied to severe PEM that lasted much longer than a couple of days. To me, PEM that lasts only 24 hrs is not a crash, it's just PEM.

I think I get what you mean. I have two levels of cognitive crash. One is in the couple of days after exertion.
For example last tuesday I was able to study for 4 hours. Felt great! I was able to chunk out another hour the next day, then nothing for two whole days. not even a few minutes of that mental energy. I was physically crashed for other reasons but not particularly the mental exertion. So that is one layer of crash.

The second layer of crash is that if I keep on using my brain each time I'm able too, after a while I will have a longer mental crash, lasting weeks, where I can't do any cognitive work. Even when my condition was milder I would have these, sometimes towards the end of a school semester. The longest was after pushing my brain consistently whenever possible for 6 months, I then had 6 weeks where I couldn't study at all and just took walks and did grocercy shopping but got no mental work done (This when my condition was 'milder' and I could often (but not always) study for 5-6 hours a day and could nearly always take a walk of some kind, while crashing afterwards). This crash type is cognitive only, physically I have whatever level of energy I would have had, which can be 'able to take a walk' or 'barely able to get around the house'.

My cognitive exertion envelope is consistently smaller than for physical exertion, which is also dramatically below a that of a normal person but not bad compared to a lot of people on here.

 

[L'engle]

I wondered once why cognitive exertion causes PEM and then realized that the brain uses a lot of energy - according to this article, it uses 20% of the body's energy despite representing 2% of its weight.

Interesting study!

I like how they cover the psycho somatic edge anyway by saying :
"However, the increased oxygen consumption could also be due to the whole body reacting to an emotional, stressful situation and not reflecting actual changes in brain activity."

We all know that ours brains get tired from enjoyable activities as well as stressful ones, otherwise ME/CFS would just be a matter of finding enjoyable enriching activities and filling our lives with them!

Still it's good that they are at least studying these things. A brain scan that showed oxygen use use somehow while people are engaged in thinking would be the next step.

I keep meaning to try BCAAs but whenever I see them in the store they have that 'gym brand' look and lots of additives. Interesting that they can help with cognitive PEM as well as physical.

 

[Mary]

We all know that ours brains get tired from enjoyable activities as well as stressful ones, otherwise ME/CFS would just be a matter of finding enjoyable enriching activities and filling our lives with them!

Wouldn't that be nice if that were all we had to do! . . . Well put -

I keep meaning to try BCAAs but whenever I see them in the store they have that 'gym brand' look and lots of additives. Interesting that they can help with cognitive PEM as well as physical.

I avoid those. I buy mine on-line - I've found Optimum Nutrition to be a good brand, and also Now Foods BCAAs. They don't have any additives.

 

[L'engle]

Jarred Younger's latest findings about low blood oxygen perfusion:

The upshot is he is interested in the possibilities of french maritime pine bark.