What is the State of Your Nervous System?
Many of you are probably familiar with the "fight or flight" response, and maybe the "rest and digest" state of the autonomic nervous system (ANS) The former is a hyper-arousal state in response to a threat and the later is a restorative state of calm in times of safety. As biological creatures, we are wired through our autonomic nervous system (ANS) to maintain proper balance of all the physiological processes in our bodies, i.e. respiratory, cardiovascular, digestive, immunological, endocrine, psychological, and reproductive. The ANS provides protection in times of perceived threat by revving up output through the sympathetic branch of the ANS or damping down the output through the parasympathetic branch of the ANS. Increasing output can take place with conditions such as acute hemorrhage, infection, extreme cold, combat, physical assault, or any situation in which the integrity of the body is threatened, or even in anticipation of any threat.
The sympathetic mobilizing output is often referred to as the "fight or flight" response which results in such physiological changes as increase heart rate, increased shallow respiration, increased muscle tension, hypervigilance, hyper-acoustics, pupil dilation, decreased digestive activity, increased pain perception and more. (See figure above) This state restricts open awareness leading to rigidity in thinking.
The parasympathetic branch of the ANS does the opposite in that is slows heart rate, slows respirations, enhances digestive process, relaxes muscles, etc. (See figure above.)
If dysregulation occurs in which ANS persists chronically in a mobilization or an immobilization state, it can contribute to many physical conditions of hypertension, diabetes, obesity, headaches, rapid aging, irritable bowel, depression, anxiety, posttraumatic stress disorder, and more. It is also being studied as possible contributor to Autism, Attention Deficit disorder Hyperactivity, and Parkinson's disease.
What is significant about Stephen's Porges Polyvagal Theory is that he describes two functions of the parasympathetic pathway. One path leads to the rest and digest state that is described as "social engagement" and the other state is shut down or "immobilization".
The relaxed state of social engagement is when there is the feeling of safety and physiological process are in balance or homeostasis. This is a state of ease and more open awareness and reciprocity with others.
The other path of the parasympathetic system is activated when the fight or flight response is not effective to escape danger and death appears imminent. The body shuts down where the pulse and blood pressure bottom out. There is loss of bowel and bladder function, Fainting and out-of-body (dissociation) experiences can occur.
The parasympathetic path is comprised of a major nerve called the vagus nerve. Vagus has the same word root as "vagabond". This vagus nerve is a wanderer through every major organ in the body (heart, lungs, liver, stomach, intestines, pancreas, sex organs, etc.) The ventral part of the vagus nerve modulates organs above the diaphragm such as the heart, muscle of facial expression and intonation of the voice. These connections are important in having social engagement,
The dorsal part of the vagus nerve influences organs below the diaphragm such as the bowels and in times of safety promote proper digestion. In time of threat immobilization state is activated and bowel tone is lost.
To summarize, according to the Polyvagal theory there are three states of the ANS: 1)social engagement -safety, 2) mobilization -threat/challenge, 3) immobilization - imminent death. The activity of the ventral vagus gives us the social engagement in times of safety. The dorsal vagus in the state of safety allows for proper digestion. However in the presence of threat or anticipated threat we activate the sympathetic system of the ANS to mobilize resources for flight or flight. If there is no way to fight or to flee then the ANS activates the dorsal vagus to go into immobilization.
For the most part the ANS operates without our conscious awareness. Stephen Porges' uses the term neuroception to denote this hard wiring of the ANS. Neuroception is the unconscious assessment by the ANS of threat vs safety. He states that experiencing traumatic events can "retune" the nervous system to be in sympathetic overdrive or dorsal vagal shut down long after the event has ended. What does this retuned unconscious risk assessment look like? It is being easily triggered into hyper-arousal or shut down without knowing why. The body responds and the mind has no clue, and so the mind may create a narrative to match the sensations of over-arousal or shut down. This is when a war veteran can return home and hear a car back fire or a helicopter fly over head and break out into a sweat and palpitations while taking a walk and feel that a passerby has something out for him because of his body sensations tell him that must be so. This is how a politician may lash out to opposing views because of a chronically vigilant feeling state in their body telling them a threat exists if someone does not share their beliefs.
So what does yoga practice have to do with this neuroscience? Yoga first is the act of inquiry to recognize what ANS state you are in. Are you in social engagement, hyper-arousal, or shut down? Sometimes this is hard to tell especially when hyper-arousal or shut down has been experienced over along time making it feel like the normal. When we take these states as normal we usually find ourselves blaming others for making us feel miserable. Or we are suspect of people who are kind-hearted; thinking that they are up to something that is no good. As a result, we may prefer to isolate, but then feel frustrated by feelings of loneliness.
After the awareness arises that a dysregulated ANS exist, then you can fell self-empowered to self-regulate your ANS through the use of yoga practices. Self-soothing techniques Certain body postures, breathing practices, and vocalizations) are used to shift from hyper-arousal to social engagement. Yoga can also provide activating practices again through different body and breathing practices to come out of shut down. The goal of any of the yoga strategies are to bring a sense of safety into the body. Safety in the body brings peace to the individual. Peace in the individual can bring peace to the world.