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Does your Brain Fog Relate to, or Coincide with, your Post-Exertional Malaise?

Discussion in 'Post-Exertional Malaise, Fatigue, and Crashes' started by Hip, Apr 30, 2011.

  1. Hip

    Hip Senior Member

    Here are some questions about your experiences with BRAIN FOG and POST-EXERTIONAL MALAISE:

    (1) Do you have brain fog (mild cognitive dysfunction) all the time, or does it vary a lot in degree from hour to hour, and day to day?

    (2)Is your brain fog worsened from post-exertional malaise (whether the PEM was caused by a physical exercise, or from intense mental activity), or is there no relation between your post-exertional malaise and brain fog?

    (3) Which limits you most, would you say, brain fog or post-exertional malaise? Which of the two would you say imposes the greater restrictions on your life? If you could cure just one of the two, which would it be? Would curing both allow you to make a substantial jump back into regular life, do you think; would curing both be the end of you CFS/ME?

    (4) Do you think the descriptions below of brain fog and post-exertional malaise are accurate and capture the essence of these two CFS/ME phenomena?

    (5) Finally, do you personally feel these two phenomena are separate things, that may occur at different times, and for different reasons, or do you feel they inextricably linked, so that one is really just a continuation of the other?

    No need to answer all these 5 questions, just the ones you think you have relevant insights into - thanks.

    Brain fog is typified by:

    Poor short-term memory (for example, you may constantly forget what you were just about to do, or what you just did).

    Poor working memory (so you cannot grasp or juggle more that a few facts or figures in your mind at one time, often making problem solving much more difficult, and making multitasking ie, paying attention to more than one thing at the same time very difficult).

    Anomia, which is problems recalling words or names.

    Slips of the tongue (semantic paraphasias), saying a different word to the one you intended often by unintentionally substituting a categorically-related item, or an item with similar qualities or characteristics, instead of the right item. For example, saying "axe" instead of "hammer" both are in the category of tools, and both have the qualities of being weighty metal implements that you strike with. It is if the brain aimed to use the right word, but missed ever so slightly.

    Miscategorization of environmental stimuli (like answering the phone when the doorbell rings).

    Lack of focus, so that it becomes difficult to remain focused on the task at hand (this is possibly related to the poor short-term memory and working memory).

    Confusion, being very easily perplexed by situations.

    Lack of awareness of the things going on around you.

    Post-exertional malaise in has been described by this blogger as:

    Not being able to be out of my bed for more than an hour a day.

    Not being able to talk too much. It takes a lot of energy for me to talk and I can only say about 200 words in an entire day. This is equivalent to you reading about 2 paragraphs out loud and then not being able to speak for the rest of the day.

    Not being able to walk very far. My limit is 100metres (or about 1 minute.) Some days my limit is less as I may go to my letterbox and back and then crash.
    I cannot tolerate much stimulus.

    My ability to cope with stress is impaired, so I purposely try as hard as possible to avoid conflict around the house.

    I am not able to think too much. For instance if I played a game of chess I would definitely crash.

    Im unable to leave my house for long. If I have been driven away from my house and spend 30 minutes in the car before returning to my house, I will crash.


    Brain fog relates to a loss of mental capabilities (such as loss of memory capabilities, stimuli discernment, focus and awareness).

    Post-exertional malaise relates to a loss of mental and physical stamina or tolerance (such as a loss of energy to move, talk, or think; such as a loss of tolerance to stress; and such as a loss of tolerance to noise and high-impact stimuli).
    Last edited: Feb 1, 2015
  2. SOC

    SOC Senior Member

    My PEM is not quite like the description given, but certainly loss of stamina of all kinds applies. Post exertional relapse is probably a better description for me.

    In answer to questions:

    (1) My brain fog is pretty consistent over the short term. It only changes hour by hour if I've overdone, which I try really hard not to do. In the longer term, however, it can change quite a bit. My brain fog is much, much less than it was a year ago, but not much different than it was a month ago.

    (2) Absolutely! Often the brain fog is most immediate symptom when I overdo. Sometimes I'll have temporary brain fog without a full PEM/PER if I catch myself and go straight to full bedrest mode as soon as I notice the increase in fog. This is since I've been better (the past year or so). Before that it was one big unending fog.

    (3) That's a hard one. Since my brain fog has improved, I have to say the PEM/PER is more limiting, but for a long time both were pretty problematic. Curing both would indeed allow me to make a substantial leap back to a regular life.

    (4) The brain fog description fits pretty well for me. The lack of awareness goes along with overdoing, especially mental or sensory. It's like my brain just shuts down and goes to survival mode, so I tend to think of it more like a PEM/PER thing, but the line is blurry. :)

    My PEM is more like PER. It's like I slide back to my worst ME/CFS period -- sore throat, swollen lymph nodes, exhaustion, muscle aches, and deeper brain fog. If I do even my normal amount (which isn't much), it all gets worse. I can talk okay, but I can't take as much stimulus. Thinking, including reading, is difficult. If I left the house, I would get worse. I find if I stay in bed for a few days, I can recover 75% from the PER. The rest takes several weeks. It's a lot like having a really bad flu.

    Since I've been better, I've had "lesser" PER, which doesn't send me to bed all day, but significantly reduces my functionality (which isn't great to start with). Brain fog plays a big part in that. My current functionality is about 50%. A bad PER will take me down to about 20% for a few days then to 30-40% for several weeks. A lesser PER will take me down to 30-40% but can last weeks to a couple of months. I'm very careful not to significantly overdo so that my "bad" PERs are not that bad.

    (5) For me, the two are closely linked. When I have a PER, my brain fog always increases. Valcyte has, so far, improved my baseline brainfog a lot, and by exercise (mental and physical) tolerance noticeably, but not as much as the brain fog yet. Before the Valcyte, the fog at baseline was bad enough that I didn't notice it getting worse with PER.

    Note: I can get a relapse that looks like a "lesser PER" from an immune insult like a vaccine (rarely), a cold, or possibly an exposure to something like flu or strep.
  3. Hip

    Hip Senior Member

    That is very interesting: that your brain fog is the first sign of an impending crash/PEM/PER episode.

    Also interesting that you say if you pay attention to the brain fog as an early-warning sign for a PEM/PER episode, and act on this warning straight away and get some full bed rest, then the PEM/PER episode may be averted.
  4. SOC

    SOC Senior Member

    My guess is that what I now call "worse brain fog" is mental exhaustion, so if I start to overdo the brain is the first thing to go. If I stop immediately and rest, I don't push myself into PER. This doesn't work if I flat-out grossly overwork in one short burst, like walking much farther than I know I can safely. That hits me like a brick a day or two later and is much worse, no matter how much I rest.

    These days I use the brain fog worsening to help me as I try to increase my activity slightly as I get better. If, at the end of the day I'm "zombified", as my family calls it, and can't remember the name of that thing, you know, you watch it -- has a remote, oh yeah, TV --then I know I'm for bedrest the next day. If I don't rest, but keep on with my slightly increased activity, then I will have PER. I learned this the hard way, of course.

    None of this worked when I was worse than I am now. Then the brain fog was bad and continuous no matter what I did.
  5. justy

    justy Donate Advocate Demonstrate

    Hi, sorry to brain fogged after a chropractic treatment 3 days ago to answer your questions but the topic does interest me. For me PEM and brain fog go hand in hand. If i didnt have both i think i would feel almost better.
    My brain fog is not quite how it is described above, i do get a worsening of cognitive function but also a very strong sense of "being out of it" like a thick hangover fug in the head with strongfeeling of reality being all "wrong" recently this had improved a lot but sicne my treatment has come back with a vengeance. For me i would love this to go away the most as it has led to me developing a phobia about going out alone as the feeling can make me panic if i feel vulnerable, so although my physical functioning has improved a lot in the past year i struggle to get out and about alone due to this one symptom.

    My pem is basically like going from Moderately affected classic M.E to more severely affrected, i get flu like aching and severe pain in my eyes adn yesterday noticed a pronounced droop to my right eyelid, alsoi become more exhausted more quickly etc.
  6. heapsreal

    heapsreal iherb 10% discount code OPA989,

    australia (brisbane)
    i class brain fog as a foggy sensation in the head, similar to a head cold, i know it can effect memory etc but i think memory and other types of symptoms are different to brain fog. My memory problems i call a brain 'fart' and to me seem different to brain fog. PEM i have found increases this foggy head feeling but dont need PEM to have the fog either. brain fog to me is sort of like a lower version of a headache, that feeling before it becomes pain/headache, as i have found the worse the fog gets it progresses into a headache or migraine, sleep deprivation i have found greatly increases this too, and my thinking reactions just become alot slower, sometimes i say 3 seconds slower then a statue, lol.

  7. RustyJ

    RustyJ Contaminated Cell Line 'RustyJ'

    Mackay, Aust
    My experience is similar to Heaps. My brain fog is as it says. In fact I started using the term brain fogged long before I had ever heard anyone else use it. (Yeh, a long time ago.) And oddly, when I first heard someone else use the term, it felt confirming - someone else knows what I am talking about!

    It feels like I am pushing my thoughts, or I am trying to reach my internal awareness, through a heavy fog with the consistency of a brick wall. It hurts to persist. If I focus, at the cost of energy, I can do it, and I pay the price. As Heaps said, there is a progression, beginning at first with a compulsion to lean against something, to walk around, or to lie down. It progresses to head ache and sometimes feels like my head is going to explode.

    I get it every day after about 4 hours upright. Movement, activity, stimulation will ease it, again there is an energy cost to do that. I work part time 8hours a week. I have to shift my mood into panic mode to get thru the work. I create anxiety about my performance, whether I can finish in time, etc to elevate any stimulation. It works.

    I think the brain fog may be unrelated to memory and cognitive dysfunction, although it exacerbates them. As far as I am concerned it is worse than my PEM. To some extent I can manage PEM, simply by resting, but nothing seems alter the brain fog (apart from the stimulation thing).
  8. Hip

    Hip Senior Member

    Although brain fog is a little bit of a vague term (like the state of mind it denotes!), as well as an unofficial, non-medical term, I believe brain fog is generally thought of as synonymous with cognitive dysfunction.

    Some descriptions/defintions of brain fog found online:

    Though sometimes you do see more general and vague definitions of brain fog, like "a cloud that reduces your visibility or clarity of mind".

    Brain fog is found not only in chronic fatigue syndrome, but also in fibromyalgia ("fibro fog"), hypothyroidism, major depression, chemotherapy ("chemo fog"), and schizophrenia.
    Last edited: May 2, 2014
  9. Hip

    Hip Senior Member


    I like that expression: "zombified". It touches on another thing that I notice about CFS/ME, which is that your level of consciousness is dimmer or lower, especially when fatigued or brain fogged.

    In philosophy, "zombie" has a specific technical meaning, namely a being without consciousness. The term zombie also refers to the real-life zombies made in Haiti (although it is against Haitian law now to make zombies; it is considered equal to murder). Haitian zombies were not unlike the Hollywood depiction of zombies: that is to say, soulless humans wondering around in a mechanical, robotic fashion, the internal light of consciousness having been removed from their minds.

    Interestingly enough, the main toxin ingredient in the Haitian zombie recipe is tetrodotoxin, a fish-derived toxin similar to ciguatera toxin (ciguatera toxin has been found in CFS patients). So I wonder if when we say we feel zombified in CFS/ME, it may literally be true in our case: there may be some toxin present that is causing this zombie-like diminished consciousness!

    For me, this zombification / impaired consciousness is generally part of the brain fog symptoms.

    I find a nice long hot bath for an hour or more de-zombifies me the best.
  10. icalla


    I did not read all the responses in detail, but am answering the original questions.

    1 - the brain fog comes and goes.

    2 - it is definitely worse with PEM, although, it does appear without it. My PEM does not show quite as described in the original post, more like SickofCFS's, it's a general, sudden worsening of all symptoms. The brain fog is more likely to kick in without PEM when I'm getting to the limit of cognitive exertion.

    3 - both are very limiting. But, since getting the hang of pacing, PEM is hardly an issue anymore, unless I choose to overdo something. So I guess if I had to choose one, it would be the brain fog. Curing both would go a long way to getting me back to normalcy, but my general energy levels (or lack thereof) would still keep me home, at this stage.

    4 - the brain fog definition, yes the PEM no, but I already answered that :p

    5 - I don't think they're separate, but I haven't found as direct a correlation as SickofCFS, for example.

    Hope these help :)
  11. lucy

    lucy Senior Member

    Hip, I really like your comparison to zombie. I am using the term "I am zombying around" when I tell my bf that I do nothing, understand not much and just let my mind go, often just randomly browsing internet.

    In fact, somebody could make a movie (fictional documentary) about post apocalyptic USA in 2044. The story would go: "in the years 2009-2011 the news about the virus hit the screens, but the state was doing basically nothing. Nobody realized that it was a zombie epidemics spreading. Differently than in fiction, it was spreading slowly, and it did not look scary - zombies were not eating any brains, they were just staying at home and being tired. In the year 2038 half of the population was infected and it was too late to do anything. The nation was getting slower, sicker and more tired... ". Then a hero researcher, a zombie himself/herself would finally figure it out with the help of secret laboratory in Russia... and all would go fine.

    Getting back to seriousness, my answers:

    (1) I have brain fog now rarely (but at the onset it was 100 percent of time), if I get one, it is when I mess up with the gut.

    (2) After exercise I am a zombie for a few days, but the brainfog is light, compared to muscle pain

    (3) As for PEM, I think I was bound to bed only when I got a cold on the top, so then I had to stay in bed, therefore brain fog is better, in the sense that you can move around like a zombie. I even noticed I do not have memories of brain fogged days, they disappear - so it is not really me, when I am brainfogged.

    (4) brain fog - yes. I also wonder if others have the tunnel vision kind of effect (it is even difficult to detect, because it is hard to understand how little your vision gives you). I could not percept more than one small thing I was seeing, it was like watching through a tube, and due to the fact that only small things were in front of me, I could not understand the bigger picture. Also experienced an inability to switch languages, while normally I use 3 languages every day.
    Cannot comment on PEM. I would be interested to know how much PEM is correlated with OI.

    (5) Brainfog is possible in many other illnesses, while PEM is very specific to CFS. But PEM without brain fog is hardly possible?

    Personally, I like to stick to blood brain barrier dysfunction as an explanation to brain fog. Also, before getting really ill (my onset was slow) I would be totally brainfogged if I got my shot of adrenaline in extreme sports. This might tell, that in my case adrenal fatigue was the one of the first to hit, other kinds followed.
  12. icalla


    Lucy, I also find it harder to speak in Spanish when I'm brain-foggy, and I'm perfectly fluent most of the time. It actually takes more effort than it's worth. I wonder if that has to do with the anomia or dispraxia.
  13. Hip

    Hip Senior Member

    Great Zombie Plot for Science Fiction!!

    That is a fantastic plot you have given for a sci fi zombie movie, lucy!

    "Nobody realized that a zombie epidemic was spreading. Differently than in fiction, it was spreading slowly, and it did not look scary - zombies were not eating any brains, they were just staying at home and being tired."

    This zombie plot is a great metaphor, one that illuminates the actual reality of the CFS/ME state: the fact that as we become sick, we become invisible, and the fact that the government is mostly oblivious to the entire CSF/ME situation.

    If the effects of CFS/ME viruses ever started to spread more widely across the general population more widely than the 0.2% to 2% of people that have CFS/ME then that is exactly what human society would have on its hands: an ever-increasing zombie epidemic, with more and more stay-at-home zombies, slowly bringing the human race to a halt!

    Is Zombification slightly different to Brain Fog?

    From reading the comments above on zombies, does anyone have a view as to whether zombification (= reduction of consciousness) can be considered as a separate symptom to brain fog in CFS/ME?

    Since getting CFS/ME, I constantly feel as if I am in a state of reduced consciousness. Even without engaging in any mental tasks or activities, if I am just sitting still, trying to come back to basic consciousness self-awareness, I find it is not there anymore in the way it used to be. I find my internal consciousness now a weak, diluted self-awareness, not sharp and intense.

    I also notice I am less spiritual than I used to be, due directly, I believe, to this reduction of consciousness.

    So I find that that I am a semi-zombie, even before I begin any tasks that may rely on my short-term memory, and so forth.

    Consciousness is anyway a mysterious faculty of the mind. Consciousness seems to be separate from the normal functioning cognition of the brain, as consciousness can be temporarily eliminated using anesthetics (during a operation in hospital), yet as most surgeons know, patients under anesthetics can subconsciously perceive and understand all the surgeons' conversations during the operation, suggesting that cognition is, at least part, independent of consciousness. (This, incidentally, is why surgeons are taught never to say things negative like "this patient is not going to survive long" during the operation, because this will utterance will be lodged in the anesthetized patient's mind, and may act as a negative hypnotic suggestion).

    Given that many neurotoxins (such as ciguatera) can reduce consciousness, I wonder whether in CFS/ME, some type of neurotoxin might be responsible for this reduction of consciousness.

    Can anyone else relate to this? Does anyone feel that they have reduced consciousness, as well as reduced short-term memory, etc?

    Don't be afraid to admit you can be a zombie sometimes!

    I am not sure about tunnel vision as such, but I have a similar thing:

    I have this problem where I cannot easily visually "scan" the environment around me (or a printed page) for something I am looking for. Previously, before getting CFS/ME, if I was looking for say a biro pen on my desk, my brain would somehow find it for me very quickly.

    This amazing ability to rapidly recognize and locate objects in a complex visual scene is called the "pop-out visual search". Our brains are normally brilliant at doing this. The visual search processing is performed by the brain subconsciously, and the item you are looking for kind of just pops-out at you.

    But now with CFS/ME, I sometimes literally need to drag my gaze over every single object in front of me, from object by object, before I find what I am looking for. OK, that's a bit of an exaggeration, but not much. My gaze is not automatically drawn to the item I'm looking for in the way it used to be. My pop-out visual search is not working well.

    As a result, when I enter into an new, unfamiliar room or environment, I feel disorientated, as I find my brain is not doing a good job at automatically scanning the room in order to assess and familiarize myself with the environment. This makes me feel is if aI am a little cut off from the environment around me.

    In an way, this failure to subconsciously scan a visual scene might be described as tunnel vision, as it feels like it is only my central vision that it taking notice of the scene in front of me.

    That is very good point, and it shows that PEM is an separate thing to brain fog, even if in CFS/ME, PEM tends to bring on brain fog.
  14. Hip

    Hip Senior Member

    The CDC teach us to prepare for zombies...

    CDC helps us prepare for a Zombie Apocalypse (tongue in cheek, of course).

    On this subject of thinking about preparedness, has anyone worried that due to some calamity - like a flood, house fire, or say wrongly arrested and placed in jail - they would be cut off from their vital supplements - the vitamins that keep the brain fog way, and so forth I get quite bad anxiety disorder if I don't keep taking my supplements.

    I have sometimes thought of putting a small emergency bag of essential supplements together (but am too lazy to do it).

    For a lot of people with CFS, the this emergency kit would not protect us from zombies, but protect us from becoming zombies (due to brain fog, etc)!
  15. Hip

    Hip Senior Member

  16. ahimsa

    ahimsa Rarely on PR now

    Interesting set of questions! I had seen this post earlier but I never got around to answering. Here are my answers for what they are worth.

    My cognitive dysfunction varies tremendously. On one of those rare days when I'm well rested from a fairly good night's sleep (e.g., I only woke up 4-5 times during the night instead of 10-12 times) then my head is much clearer. So simple exhaustion from a bad night's sleep (not necessarily even PEM) can also contribute to my problems with brain fog.

    My NMH (Neurally Mediated Hypotension, a type of Orthostatic Intolerance) also contributes to my brain fog. Ask me a question while I'm standing up and I'll probably go into "deer in the headlights" mode while my mind feverishly tries to understand the question, formulate an answer, and then convert the answer into words (which is the very hardest part!). Ask me that same question while I'm resting in the recliner or, even better, while I'm lying down, and I will probably have no problem. So, for me, I know that part of my cognitive dysfunction is lack of blood to the brain (demonstrated so clearly by my passing out on two different tilt table tests). I often joke that my IQ goes up at least 30-40 points by lying down.

    It's always worse when I am exhausted (whether from PEM or a bad night's sleep).

    My physical limitations (not just PEM from overexertion but also the other physical symptoms) have a much larger impact on my ability to function than my brain fog. I think that my cognitive dysfunction may be worse now than when i first got sick but my physical limitations are still my biggest problem.

    But I would have to cure my NMH, which is not listed in your question, to come anywhere near being back to what I used to be. With NMH, even with the prescription drugs and extra salt/water that I'm taking, I can't stand in line at all, or even sit upright for any length of time. I think that, for me, part of the PEM/PER is caused by the NMH. If my body is going into pre-syncope all the time (e.g., the dropping blood pressure leading to the symptoms you get just before you faint) then is that contributing to the PEM/PER for me? Or even the main cause of it? Who knows....

    The brain fog description seems pretty good to me. I don't have all the symptoms but it's a pretty good match.

    For my own experiences with PEM/PER, the description seems lacking. I have more physical symptoms. For example, there's a flu-like feeling, along with some body aching, along with the lack of energy. There's shortness of breath and several other symptoms (can't remember off the top of my head). Also, my NMH is much worse (more rapid heart rate, less ability to stand, and so on).

    Even though the PEM can influence the brain fog I do think these are two separate things. My cognitive dysfunction seems to be impacted by exhaustion and also by lack of blood flow to the brain. It depends on the situation. Even when I'm relatively well rested, no PEM, I will have some brain fog if I have to think while I'm standing up.
  17. mellster

    mellster Marco

    San Francisco
    I don't think I ever experienced brain fog as described here. With PEM my head hurts and is heavy, spacey, sometimes a bit noisy (akin to tinnitus) and foggy prob due to reduced oxygenation, so concentrating becomes obvously diffcult, eso. for a timeframe longer than a couple of minutes, but when I force myself I realize that except for the fatigue/exhaustion/headache my mind is absolutely not impaired at all. Some of the symptoms mentioned like word slips and similar issues probably happen to "normal" super-tired people as well. So I think it is important to really carve out the cognitive symptoms that cannot be solely attributed to extreme fatigue and that also happen during non-fatigued states in order to make the right distinctions.
  18. slayadragon

    slayadragon Senior Member

    This is very cool. Thank you.

    Best, Lisa

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