ME & Stress: Limbic Kindling
How stress may cause ME
It is not known for sure what causes ME, but it is looking increasingly likely that ‘nervous system overload’ has a huge role to play. One theory that has been proposed is the Limbic Kindling theory, which focuses on the role of stress.
As I explained in Stress: Part 1, to your body, ‘stress’ doesn’t just mean emotional stress. It can also be things like an infection (viral, bacterial, fungal/mold), physical or mental trauma, inflammation or even environmental toxins such as pollution, pesticides and heavy metals (eg mercury or lead). Your body responds to all of these (and more) with its stress response (‘fight or flight’).
The exposure to the stress can either be a short-term but high intensity exposure (for example, a brain trauma) or it could also be a repeated longer-term exposure at a low (sub-threshold) level, ie one which does not produce symptoms. But both eventually lead to a persistent hypersensitivity, ie the person gets into a state of chronic stress, whether the original source of stress is still present or not.
When the body’s stress response keeps being activated (chronic stress), this has a number of effects in the body: you feel tired, your ability to digest is reduced, and your immunity is affected: you become less able to fight off infections, you may experience swollen glands and there is an increased risk of developing allergies, intolerances, hypersensitivities or autoimmune disease. It alters your hormones and neurotransmitters, leading to symptoms such as poor memory and concentration, ‘brain fog’ and to depression and anxiety [see also Stress: Part 2].
Kindling was originally discovered in 1967 by Graham Goddard while studying the effects of electrical stimulation on the amygdaloid complex in the brain. He found that long-term low intensity and intermittent electric shocks to the brain caused spontaneous, epileptic-like seizures even when no stimulation was given. Similar results were produced using chemical stimulation. Ashok Gupta was the first to propose a similar theory as the basis for CFS/ME: that an infectious, chemical or psychological stressor could create a “cell assembly” within the unconscious amygdala that was particularly resistant to elimination, ie people became “hard wired” to produce an exaggerated and unhealthy response to stress. Other studies on PTSD confirmed the accuracy of the Kindling hypothesis.
This diagram is from Ashok Gupta’s paper “Unconscious amygdalar fear conditioning in a subset of chronic fatigue syndrome patients” (2002)
How stress keeps ME going
Unfortunately this relationship between stress and ME is bi-directional. Chronic stress has many effects on the body including increased oxidative stress, inflammation, gut dysbiosis and toxin build-up. These, in turn, act as stressors on the body and hence cause more limbic kindling. This vicious cycle may explain why illnesses like ME/CFS and fibromyalgia persist long term.
The psychological link
The Limbic Kindling theory illustrates the interconnectivity between the mind and the body. Certain personality types, such as being an over-achiever, an excessive ‘helper’ or having high anxiety have been shown to be risk factors for developing ME/CFS. Emotional trauma in childhood is another well-established risk factor for the onset of ME/CFS (and other inflammatory and autoimmune disorders) in later life.
Therapies
Commonly-used techniques for stress management and neurological reprogramming to reset the unconscious amygdala include NLP, EFT, CBT, EMDR, NAET, yoga, Qi Gong and meditation. Saunas and chelation therapy may support detoxification.
There is so much that nutritional therapy can do to support ME - I cover this separately in my post on ME and nutrition.