These Australian researchers, overseen by Dr. Vollmer-Conna, begin their quest for the source of the cognitive difficulties in chronic fatigue syndrome by turning things on their ‘head’ (pun intended) a bit.
PLoS One. 2012;7(11):e49518. doi: 10.1371/journal.pone.0049518. Epub 2012 Nov 14.Reduced cardiac vagal modulation impacts on cognitive performance in chronic fatigue syndrome. Beaumont A, Burton AR, Lemon J, Bennett BK, Lloyd A, Vollmer-Conna U.
They noted that each of the cognitive abnormalities in ME/CFS appears to be fairly mild but taken together there are enough of them to perhaps turn them into something significant.
An Aside – The finding that the cognitive abnormalities test out as relatively mild in this disorder will undoubtedly cause people with really severe cognitive issues to shriek in dismay but it surely reflects the heterogeneity in our population. There are people like me – who test out with some cognitive dysfunction but who are fine otherwise and people who literally can’t read anymore and who probably don’t show up in many studies.
Also, few studies incorporate the issue of cognitive post-exertional malaise into their designs. Exertion is exertion. People with ME/CFS can ‘fake it’ for a while; they can make it through that first day of work or that first hour of testing OK; it’s the second or third or fifth day, or that second or third hour, when things start to go south. Most cognitive tests, though, don’t capture ‘the fade’….
In any case, throw all the ‘mild’ issues together and you do have something significant.
Figuring out the ’cause’ of those issues (the slowed response speeds, the low working memory) hasn’t been easy. Since both of these are found in depression, depression seemed to be an easy answer given that, well, ME/CFS is a depressing illness, but attempts to link the cognitive problems in ME/CFS to depression have failed. (Collective groan from the psychologists….)
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In an earlier study this group found that heart rate variability (HRV) tests explained sleep issues better than classical sleep tests (REM sleep, sleep architecture problems, etc.) so they tried that approach again, this time with cognitive issues.
Seventy people either with ME/CFS or as healthy controls did a series of self-report symptom and psychological tests and cognitive tests designed to challenge various cognitive areas (working memory, sustained attention, response flexibility and speed) while they were hooked up to an electrocardiograph (ECG) that measured heart rate.
The Missing Plateau
More broadly, our findings add to the growing body of evidence linking autonomic dysfunction to the symptomatology in this poorly understood disorder.
ME/CFS patient performance on accuracy and spatial working memory results were similar to the healthy controls, but they had slower reaction times. In contrast to the healthy controls heart rate which increased early in the test and then leveled off, the ME/CFS patients heart rate was increased at baseline relative to the healthy controls, then increased, and then continued to increase throughout the test in the ME/CFS patients.
‘Post-Exertional’ Without the ‘Post’ – System Overshoot in ME/CFS
“a loss of sensitivity to task difficulty”
In this case the study revealed chronic fatigue syndrome patients were over 10 x’s less likely to return to their resting heart rates (which was in any case increased :)) in the first minute of the recovery period than the healthy controls.
The authors called this inability to quickly return to a ‘baseline’ “a loss of sensitivity to task difficulty”. The CFS patients’ systems continued on as if they were still engaged in a difficult task, when in fact they were not. We’ve see this kind of overshoot in which ME/CFS patients have trouble turning off a system once it gets turned on several times.
The heart rate variability (HRV) readings – which measure the robustness of the autonomic nervous system – were almost ‘significantly’ (p<.06) reduced in the ME/CFS patients. (More variable is better with regards to heart rate variability.) During the test that same ‘missing plateau’ pattern returned, with the HRV readings dipping as the healthy controls were put under the stress of the cognitive tests but then plateauing, while those of the ME/CFS group dropped and dropped and dropped.
(Does it ever seem like you’re expending too much energy to produce a task? Muscles ever feel tightened as if you were about to try to pick up a truck when all you’re trying to do is pick up a book? I find that I often exert myself in easy tasks as if they’re difficult ones. )
Accuracy – Yes, Speed – No
A correlational analysis found that the slower reaction times in the chronic fatigue syndrome patients were not associated with somatic symptoms, levels of psychological distress, degree of functional impairment, or even fatigue or energy, but appeared to be ‘highly significantly’ related to the reduced HRV readings.
This is a BIG finding. People with depression or psychological distress can have reduced performance speeds and it would make sense that fatigue would at least be associated with reduced cognitive speed, but it wasn’t either; instead it was the reduced heart rate variability readings – those findings that indicated the ANS was imbalanced, that were significantly linked to cognitive issues.
Having reduced performance speed doesn’t mean being a bit slower – it also means more difficulty concentrating and focusing. It takes a certain amount of cognitive speed after all, to keep up with someone’s conversation…
This finding put the autonomic nervous system right in the bull’s-eye of a major symptom in ME/CFS.
More Work, More Energy Expended = More Fatigue
ME/CFS patients were as accurate as the healthy controls at the tests, but their slowness made the tasks more effortful – hence the much greater degree of mental fatigue reported by our slower processors – the ME/CFS patients.
The Cost of ‘Distraction’
Interestingly, the ME/CFS group’s response speeds were all over the map, which appeared to reflect patients’ focusing on their task, getting their focus knocked off, and then refocusing again…(Note that the healthy controls simply focused on the task and responded.)
Imagine how much more energy it takes to focus on something, lose your way and then have to refocus on it do this again and again and again, instead of simply staying with the objective. Nailing a key problem, the authors aptly referred to the ‘ongoing struggle to keep attention focused on the task at hand’ which the chronic fatigue syndrome group had.
The Brain/Body Connection and a ‘Loss of Dynamic Flexibility’
Heart rate variability (HRV) tests in ME/CFS have indicated that the fight or flight side of the ANS (the sympathetic nervous system) is going gangbusters while the rest and digest side (the parasympathetic nervous system) is going to sleep. That hyper-vigilant state – that constant feeling of ‘being in danger’ – results in reduced activity of pre-frontal cortex – which is involved in planning and organization – and ‘vagal control’ – which tells the body to ‘rest and digest’.
Under normal circumstances, the prefrontal cortex tells the fear center of the brain, the amygdala, that everything’s OK – that you can quiet down now – but if the brain is in hypervigilant mode; ie if it thinks its survival’s at stake, it will blow off the prefrontal cortex’s signals to calm the body down.
The authors pointed out that ‘increasing evidence’ suggests that chronic fatigue syndrome patients exhibit a kind chronic, sympathetic nervous system based state of ‘hyper-arousal’ present even when they are asleep. ( I imagine army sentries put out at their posts waiting, waiting for the attack without relief…..Something certainly is going to give at some point. )
Little wonder, the authors speak of a system that has lost ‘dynamic flexibility’ – an term that resonated with me. Among other things, having ME/CFS has been synonymous with a loss of grace and spontaneity – a loss of a kind of ‘dynamic flexibility’ that was present before.
The Vagus Nerve
Why the inability to ramp down and turn off the ‘arousal’? It probably has something to do with the vagus nerve. It’s the vagus nerve, after all, that’s responsible for turning down the heart rate at the end of a task and telling the body to rest. Several times the authors called the vagus nerve ‘sluggish’. Let’s take a look at this interesting nerve.
This novel finding supports our results obtained from HRV and indicates that CFS is associated with a significant loss of vagal modulation which becomes particularly apparent when dealing with challenging tasks.
Derived from the Latin word for ‘wandering’, the vagus nerve emerges from the brain stem and then ‘wanders’ all the way down to the abdomen, branching off along the way to receive information from and then regulate heart, lung, voice box, stomach and other activity. Every time your heart beats, every time you breathe, every bit of food you digest, and every time you move your muscles, you’re using the vagus nerve.
The vagus nerve generally doesn’t initiate activity, it regulates it. In service of the parasympathetic nervous system (i.e., the rest and digest system), the vagus nerve turns down the heart beat, reduces the breathing rate, lowers our blood pressure, stops abdominal motility in order to give food a chance to digest, etc. The ying to the sympathetic nervous system’s yang, the vagus nerve is responsible for turning the fight/flight response off.
Next Up – we ‘re going to follow this thread a bit deeper over the next week or two. We’re going to look at cardiovascular issues and cognition, check out the Dr. De Meirleir video on circulation, examine two models of ME/CFS and then wrap up with a look at stunning study that just might throw everything together.
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Sluggish Vegas nerve, as in tired? I don’t think so. Suffering from infection from whatever pathogen, yes. And, down regulated, as a protective measure? Probably.
I believe, much that goes on in CFS patients, is a reaction of conservation and self preservation, due to infection and/or damage from infections.
As an aside, I would add, it appears we are very deficient in Magnesium and vitamin D3 and to a lesser extent, all the other minerals, including Selenium, the anti-cancer mineral.
Not to mention, we are also, way too Acidic! RP
I think you may be right about the conservation and self-preservation part….We’ll find out about the infection pretty soon. My guess is active infection in 20% – That makes me think of doing a poll….What effect does being too acidic have?
Wow! Thanks, Cort, for such an insightful review of the study.
I certainly relate to trying too hard to do just about everything I do. Even when I consciously tell myself to just do 20% of my default mode, I end up exerting more energy doing both mental and physical tasks than is necessary. And I’ve been mystified as to why I can’t seem to regulate this more easily.
It’s great to know that research is starting to find out more about why this is. Thanks for helping us stay up on the findings.
Thanks Sarah…exerting alot over little things is one of the most peculiar things about this illness for me. It’s almost as if my body is exerting alot of energy just to keep itself together, and in this connection, I wonder about Ehlors Danlos Syndrome, which is characterized by lax muscle joint connections I believe.
My system just seems to be ‘on’ most of the time…
It is like you have told my story – I function the same way as well.
Thank you Cort!
Glad to hear it Eva. (I feel a little weird saying that 🙂 but its good to know others are in a similar situation.
🙂 – so it does
Excellent work Cort. Do you know if there is another disease exists with this problem? Where there is also a constant” overdrive”? I think this is the central problem in ME. About the cause we can only speculate for now. But that’s no problem.
“Neurobiological research indicates that PTSD may be associated with stable neurobiological alterations in both the central and autonomic nervous systems. Psychophysiological alterations associated with PTSD include hyper-arousal of the sympathetic nervous system, increased sensitivity and augmentation of the acoustic-startle eye blink reflex, and sleep abnormalities.
Neuropharmacologic and neuroendocrine abnormalities have been detected in most brain mechanisms that have evolved for coping, adaptation, and preservation of the species. These include the noradrenergic, hypothalamic-pituitary-adrenocortical, serotonergic, glutamatergic, thyroid, endogenous opioid, and other systems.
Structural brain imaging suggests reduced volume of the hippocampus and anterior cingulated. Functional brain imaging suggests excessive amygdala activity and reduced activation of the prefrontal cortex.”
That’s interesting…ha…well, get ready for a controversial blog next week on this very subject….
Seems like Autism might have similarities in this area – especially as it relates to easy distraction.
It seems quite likely – I’ve been told in hushed voices by two different “experts” – about ANS and brain “damage” but the elephant in the room (apologies to Dr. Friedman) is how that happened. Either they have absolutely no clue or there are reasons that TPTB don’t want revealed.
I think it’s reasonable to contemplate that the CDC et al don’t want it known that a good portion of the population is brain damaged – especially when you start including Autism, Alzheimers, MS, Parkinsons, etc. – and they can’t do jack about it. Not good for confidence in the “system” that is sucking up wealth at an increasing rate but doing little to improve “health” for huge slices of the population. Take the red pill Neo…
As I understand it, impaired parasympathetic function is common in many chronic illnesses and pretty much the norm in the aging population.
I’m pretty sure that’s not what’s going on here though (i.e. as a downstream effect of chronic illness). Too many people with ME/CFS (and young people) have these problems from the off.
Marco the parasympathetic nervous system directly interact with the immune system i.e. macrofagen within the stomach…. and shift to TH2…. This route can explain everything in this disease. But what causes it, i don’t know. Infection, damage, genetic, the brain….?
In an upcoming blog, some researchers are going to focus on a part of the brain that’s upstream from the vagus nerve…which appears to regulate it…something of a surprise to me…The plot thickens!
I wouldn’t be surprised if many of the so-called allied disorders share this. Similar findings are found in fibromyalgia and perhaps IBS and I think they are found in some other chronic illnesses, although I’m not sure what they are.
Naschtiz, an Isreali researcher, did alot of work with ‘cardiovascular reactivity’ in ME/CFS about 10 years ago and then the work just stopped. Check this out…he was talking about a frigging biomarker 10 years ago with these analyses and he’d assessed ME/CFS against other disease groups using tilt table tests…He was way ahead of everybody…..
The diagnosis of chronic fatigue syndrome (CFS) is based on patient history and treatment on cognitive behavior therapy and graded exercise. There is increasing evidence that dysautonomia occurs in CFS manifest primarily as disordered regulation of cardiovascular responses to stress.
We impart our experience relating to diagnosis, monitoring, and treatment of CFS based on identification and management of dysautonomia. Recently proposed methods for assessment of the cardiovascular reactivity, the ‘hemodynamic instability score’ (HIS) and the ‘Fractal and Recurrence Analysis-based Score’ (FRAS), served for this purpose.
On HUTT, a particular dysautonomia is revealed in CFS patients that differ from dysautonomia in several other disorders. This distinct abnormality in CFS can be identified by HIS >-0.98 (sensitivity 84.5% and specificity 85.1%) and FRAS > +0.22 (sensitivity 70% and specificity 88%). Therefore, the HIS and FRAS may be used, in the appropriate clinical context, to support the diagnosis of CFS, which until now, could only be subjectively inferred.
A pilot study suggested that midodrine treatment, directed at the autonomic nervous system in CFS, results first in correction of dysautonomia followed by improvement of fatigue. This finding implies that dysautonomia is pivotal in the pathophysiology CFS, at least in a large part of the patients, and that manipulating the autonomic nervous system may be effective in the treatment of CFS.
Here’s an earlier paper that assessed heart rate and pulse time against other disorders
This study aimed to develop a method to distinguish between the cardiovascular reactivity in chronic fatigue syndrome (CFS) and other patient populations. Patients with CFS (n = 23), familial Mediterranean fever (n = 15), psoriatic arthritis (n = 10), generalized anxiety disorder (n = 12), neurally mediated syncope (n = 20), and healthy subjects (n = 20) were evaluated with a shortened head-up tilt test (HUTT).
On multivariate analysis, the best predictors of CFS were HR-tilt-R/L, PTT-tilt-R/L, HR-supine-DET, PTT-tilt-WAVE, and HR-tilt-SD. Based on these predictors, the ‘Fractal & Recurrence Analysis-based Score’ (FRAS) was calculated: FRAS = 76.2 + 0.04*HR-supine-DET – 12.9*HR-tilt-R/L – 0.31*HR-tilt-SD – 19.27*PTT-tilt-R/L – 9.42* PTT-tilt-WAVE.
The best cut-off differentiating CFS from the control population was FRAS = + 0.22. FRAS > + 0.22 was associated with CFS (sensitivity 70 % and specificity 88 %). The cardiovascular reactivity received mathematical expression with the aid of the FRAS. The shortened HUTT was well tolerated.
The FRAS provides objective criteria which could become valuable in the assessment of CFS.
” frigging biomarker”
That a technical term Cort? 🙂
Yes, it refers to a particular kind of biomarker -the kind that could change everything in a controversial disorder but always seems just out of reach..they’re also sometimes known as *(&(&ing biomarkers… and those ^%&% biomarkers 🙂
Not very descriptive on what the “stress” is. I don’t disagree with the premise but that’s just the tip of the iceberg. I have dysautonomia but it’s not coming from exercise or “stress”. My best guess with some pretty good evidence behind it is environmental issues – particularly severe temperature dysregulation.
I hope if they go in this direction the “stress” factor is induced before testing. However this is problematic due to “ethical” concerns. I’ve had this discussion with Klimas and it’s hard to understand why it’s fine to force exercise on people but not expose them to say Napthalene before during testing.
I wonder if the “stress” was due to pschological issues they would consider inviting Simon Wessley to babble on and on while testing was being conducted 🙂
Nice one 🙂
We are lagging far behind in Australia. In many countries the Non Transdermal patch is found to improve many quite serious conditions and is already showing amazing results. Safe, easy to use, low cost, no side effects with a host of clinical trials and studies completed and ongoing. This patch, communication as light in the Infra Red spectrum, is even being intoduced into hospitals in France but appears too far advanced just yet to be considered in Aus?
Interesting article, Cort. Thank you for the best explanation I’ve read about HRV as it pertains to ME patients!
I wonder how these sympathetic nervous system findings fit in with what we already know from the work of Staci Stevens et al. that we spend most of our time in anaerobic metabolism (reduced oxygen (VO2), causing significantly greater than normal use of anaerobic rather than aerobic energy, coupled with our early AT problems — that we cross our anaerobic thresholds with very little exertion). Activities requiring minor exertion feel more difficult because we’re forced to use the inefficient anaerobic energy system, instead of the efficient aerobic one … We just can’t make use of the oxygen. I wonder how the 2 sets of findings are related … does one problem cause the other or do they both independently contribute to PEM/PENE?
Hi Cort – great article – as you know this is exactly what I have been saying – so no surprise it resonates with me! – 🙂
The sooner everyone comes on the same page regarding the cause of ME/CFS and Fibromyalgia, the sooner people can focus on what needs to be done to recover!
I think this type of research is great and think that is is inevitable that it is just a matter of time before ME/CFS and Fibromyalgia will be recognised as being caused by brain dysfunction that causes dysautonomia and the problems with pain perception.
It’s interesting so see the mention of Simon Wessley above. I think that people’s concern about anything “psychological” is really holding back the acceptance of this explanation, even though clearly that is ONLY one aspect of the illness. I suspect that is part of the reason why these researchers are reluctant to come straight out and discuss their research finding in the context of a causal factor, it’s the fear of retribution.
The word ‘stress’ still gets a rise in the community, because people don’t make the connection that physiologically speaking, going for a run, getting an infection, having surgery, having a baby, being emotionally abused or having psychological upsets are all ‘stress’ and responded to similarly by the ANS. That’s why I am such a strong advocate for a multi-lateral appoach to recovery. So whilst psychological stress may not have caused everyone’s illness in the first place – it sure doesn’t help whilst trying to recover!
The problem seems to be the fact that for so many years, so many of us were told that we were imagining the illness or making it up, which of course is ridiculous and very unfair. Who can blame us for being a bit oversensitive when to comes to research or explanations and commentary that makes the mind-body connection!
Hi Dan, if you take the ‘stress’ away people still stay sick with ME/CVS. Your focus is very subjective. We need objective markers to proof the concept. I do not believe ‘stress’ is the problem. It is pure somatic. Why can the overactive ANS respons not calm down anymore?
It’s because “stress” is a waste bin word. It can mean anything to anyone. As the poster below says, when there is a definition of stress and it is objectively measured then I might listen until then it’s nonsense.
I see this condition – at least for some – like Celiac Disease or Mast Cell Activation. Gluten or everyday things cause a “stress” response far in excess of what is appropriate. Do you think lowering people’s “stress” levels would be a better method than say avoiding gluten or the mast cell triggers? Do you think Sir Simon would be effective treating somebody that wasn’t aware they had Celiac while they down pasta, bagels and other gluten products?
We might agree that some people might benefit from some “psychological” assistance in dealing with the abnormal reactions that occur from the above conditions. What Simon and YOU seem to be advocating is that CBT alone will solve the problem for every patient diagnosed with ME. I disagree. However, it might be an effective therapy for those patients the CDC studies in Atlanta and Wichita.
My interpretation of Dan’s idea, and I don’t want to put words in his mouth is that avoiding gluten or mast cell triggers could be a kind of ‘stress avoidance’ behavior. Anything that impacts the ANS is a potential stress – so if those things do, and I don’t know that they do, they might.
He suggests that all sorts of different kinds of stress – “going for a run, getting an infection, having surgery, having a baby, being emotionally abused or having psychological upsets” are responded to similarly by the ANS – so I think those may fit but I’ll wait for Dan’s response.
I will note that other studies are also finding that stress or anxiety are not major factors in pain or cognition but that autonomic nervous system issues are. The ANS appears to come first and I love to reduce my psychological stress as well…It helps 🙂
A recent case report was published of a person with CFS who developed a fever when she was put under psychological stress – http://www.ncbi.nlm.nih.gov/pubmed/23497734. Hey, when your system’s messed up it’s messed up – and just about anything can cause problems. That’s my experience.
Yeah, but the point is it’s tough to properly avoid “stress” if you don’t know the source. Like I said in my post no amount of CBT and magical thinking is going to help someone with Celiac if they don’t know first and foremost to avoid gluten.
It’s tragic so much effort goes into providing emotional support for this disease rather than investigating root cause issues.
Maybe another poor analogy but one would hope that if you went into an MD’s office complaining about a headache with a pick ax embedded in your skull the response would be to remove the pick ax not take Advil and encourage one to do yoga and CBT to deal with the pain.
Agree completely Floydguy…:)
Gijs, you are asking the right question about why.
Of course I am not suggesting that there is just too much stress (and thanks a lot for explain the word stress on my behalf Cort) and hence we are in all sorts of trouble. Because clearly other people can have all manor of extreme stress including all the things I mentioned, even including some of our bodily dysfunctions, AND they don’t have CFS or Fibromyalgia!!!
The point is that the ANS is dysfunctioning because it has been unable to bring the stress to it’s natural conclusion through normal regulation. So neither the freeze or flight response is resolving the issue in a reasonable time frame and so we have moved from natural sensible regulation and response to basically a really poor emergency putting out the fires knee jerk control. (I apologise for my poor wording here).
floydguy, please don’t pop Simon and I in the same basket, I don’t even know what he fully stands for AND I don’t think that CBT alone can fix this for most (although I am not saying that might not have worked for some – I also wouldn’t put all CBT in the same basket, it’s about how targetted it is).
In fact, that is my main point. I am bascially saying that none of the ‘single treatment cures’ out there are much good for all of us AND that many of them are essential for our recovery! – confused?
Let me explain. I have always advocated that people need to reduce the MAJORITY of the their major stressors for a period of time and then ‘rewire’ their system to work normally again. So I am suggesting a multi-lateral approach that whilst having a lot in common for everyone (some core treatments and strategies that are very powerful and important), will also need to be suplemented with specific treatments and address specific issues that are more unique to the individual. This goes for both addressing physiological and psychological stressors. So don’t get all caught up on treating parasites and yeast infections if you don’t have these – makes sense, right! And don’t get caught up in resolving your childhood emotional abuse, if it never happened! Etc etc.
I hope you can also see the self-perpetuating nature of all this. Think about it guys, when you feel really horrible with ME/CFS or Fibro flare up, don’t you ever get so that you just need peace and can’t take any stress? So normal stresses that when you were healthy were like “whatever”, now become SEVERELY stressing. Well, it’s the same for the physiological stuff. When I skip breakfast and go for a run and not eat till the afternoon – “whatever”. When I didn’t eat or exerted myself when I had ME/CFS/Fibro – DISASTER!
So the root cause in my view is the breakdown of the functioning of the ANS, because it was overwhelmed for whatever reason and has not had the opportunity to ‘reset’ itself for lack of a better word. This dysfunction deepens in nature over time as inappropriate triggers accumulate, which can be just about anything.
Hi Dan, we agree that there is a real problem with the ANS for most of us. But i still do not have a good answer to my guestion. Your ”therapy” is focus on ”relax” this system. That is not a solution. If it is, you do not have ME but a burnout. A burnout have the same problems. The different between these two is that a burnout can be fixed by your approach ME not. The ANS has been ”broken”. I still don’t have an explanation why the ANS is in overdrive and react abnormal on every stimuli.
Another beautifully-written piece setting the bar very high for the rest of us who like to blog from time to time!
But in my role as research study Wet Blanket, I wanted to point out a few issues:
– the main finding, that HRV predicts cognitive performance, is as true in healthy controls (and in other studies too) as it is in CFS patients, so it’s not clear quite what this tells us
– The differences in pattern of HRV between patients and controls during testing were on the margins of significance and the effect size wasn’t big. More and bigger studies are needed to confirm this finding
– However, the finding that Heart Rate takes much longer to recover after cognitive testing in patients is a ‘first’ and it was a big effect too (maybe such a big difference because the patients found the tests so much harder?)
– I find it amzing that mental fatigue both before and after testing, or pereceived effort, did not predict cognitive performance, yet this has been found in other studies too, notably in a recent study by fellow Aussie researcher Susan Cockshell (http://forums.phoenixrising.me/index.php?threads/brain-fog-the-research.22947/)
more analysis here: http://forums.phoenixrising.me/index.php?threads/heart-rate-variability-may-help-to-understand-chronic-fatigue-syndrome-cfs.20444/#post-358094
Thanks for keeping us honest Simon 🙂
I am currently seeking the answer to how to switch off. I have recovered massively in the last couple of years, mostly by realising the pyschological factors influence my illness greatly, but it has only recenlty become clear to me that when I feel good, my energy pumps out and goes on and on until it goes below par and I stay that way.
The vagus nerve being involved ties in with the fact that if the vagus nerve is responsible for producing sickness symptoms whether there is a virus etc or not. I think that may be what happens, my body produces sickness symtoms in the absence of a pathogen, as a form of protection, perhaps.
If you can point me to where I could look next I would be so grateful.