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Inspiration
Acu. | Issue #31 | Summer 2021
The shen & nervous system regulation in a year of uncertainty Naava Carman Member: London The past 12 months turned into a pretty hard year for everyone. While some of us clearly fared better than others, the pandemic has had an impact on us all at a psychological and physiological level. Understanding the autonomic nervous system has become increasingly important in my clinical practice of TCM over the past year, as I saw many clients who were simply burnt out by the experience of going through the pandemic.
About the autonomic nervous system
The autonomic nervous system (ANS) connects our brain, spinal cord and our organs. It regulates all our unconscious functions like digestion, respiration, heart rate. The ANS has two states: the parasympathetic state allows us to rest, digest and heal, while the sympathetic state is there to deal with threats and drives our ‘fight or flight’ responses. Ideally, we want to be in the parasympathetic state as much as possible. This will allow us to digest our food properly, to register when we are full, to be relaxed enough to sleep properly and to regulate our circadian rhythms. Regrettably, over the course of a year when everything was uncertain we have all spent far too much time in the sympathetic state – mind and body primed to deal with both actual and potential threats on the horizon. The measures required to keep ourselves safe – staying at home, not being able to hug our loved ones or engage in shared experiences, avoiding people outside of our bubbles, and hiding our smiles behind masks – robbed us of many of the tools that we needed to help us move from the sympathetic state back into the parasympathetic state. ANS dysregulation has huge implications for health. The parasympathetic state relies heavily on the vagus nerve (cranial nerve #10), which innervates the lungs, liver, spleen and kidneys, and provides bilateral communication between our brain and gut. In the vagus nerve, around 20 per cent of the nerve fibres are sending messages from the brain down to the body, and 80 per cent are sending
messages up to the brain. As such, the vagus nerve is an essential part of how, when we are in a parasympathetic state, our brain listens to our organs before issuing instructions. This stands in contrast to how we behave in a sympathetic state, when our brain uses the senses to inform decisions about how the organs and muscles should act. If we are spending too much time in the sympathetic state then messages between our gut and brain are not conveyed correctly, as the brain is not listening to the signals from the vagus nerve. This compromised communication blocks the release of the neurotransmitter GABA (gammaaminobutyric acid), which helps
inhibit anxious thoughts. Sitting in the sympathetic state, with its prioritisation of physical action, also weakens the immune system, which can allow opportunistic pathogens to gain a toe-hold. This sympathetic state can also heighten physical and emotional pain and fatigue.
Applying ANS knowledge in TCM
Whilst all the major zangfu organs influence the function of the ANS, having read many biomedical and TCM books and studies around the nervous system and trauma, I concluded that my main focus should be on the heart, the shen and the pathology that arises when they are unbalanced.
