The following is excerpted from Fasting the Mind: Spiritual Exercises for Psychic Detox by Jason Gregory, published by Inner Traditions.
The spiritual path of Buddhism came into existence as a result of this yearning to completely slow down our nervous system so we can experience real freedom. In Sanskrit such freedom is called nirvana, meaning extinction, freedom from suffering, and ultimately the unconditioned eternal reality that we experience as enlightenment. In the story of Gautama the Buddha, he sought methods of practice and philosophy that would evoke the state of nirvana. He followed asceticism and strict spiritual practices for six years. It wasn’t until he was exhausted in his efforts that he finally took some milky soup from a young girl herding cattle and sat under the famous Bodhi tree in the small town of Bodh Gaya, India. In doing so, he completely relaxed without the need for striving. His original efforts had been futile because he was approaching enlightenment in the same way that we purchase a cheap suit. In striving for anything, there is still agitation in the mind, and this perception of life comes from the ignorant view of how we supposedly achieve things in this world.
Whether knowingly or unknowingly, Gautama the Buddha accessed a part of our nervous system that remains dormant when we are always in physical and mental motion. This part of our nervous system is known as the parasympathetic nervous system (PSNS).
To gain a better understanding of this we need to know what makes up the nervous system. The nervous system is the part of an animal’s body that coordinates its voluntary and involuntary actions and also transmits signals to and from different parts of its body. In vertebrate species, such as human beings, the nervous system contains two parts, the central nervous system (CNS) and the peripheral nervous system (PNS). The central nervous system contains the brain and spinal cord, while the peripheral nervous system consists of mainly nerves, which are enclosed bundles of long fibers, and axons, which are long, slender projections of nerve cells that conduct electrical impulses away from the neuron’s cell body. These nerves and axons connect the central nervous system to every other part of the body. The peripheral nervous system is divided into the somatic nervous system (SoNS) and the autonomic nervous system (ANS).
The autonomic nervous system is our central focus when related to psychological or spiritual inner work and transformation. The autonomic nervous system is a control system that largely acts unconsciously and regulates our bodily functions such as heart rate, respiratory rate, digestion, pupillary response, urination, and sexual arousal. The autonomic nervous system has two branches: the sympathetic nervous system (SNS) and the parasympathetic nervous system (PSNS). The sympathetic nervous system is sometimes considered the “fight or flight” system because it is activated in cases of emergencies to mobilize energy. It is what we activate when we are in motion and being stimulated through our senses. Without it we could not do anything. The parasympathetic nervous system, on the other hand, is often considered the “rest and digest” or “feed and breed” system because it is activated when we are in a relaxed state. We activate the parasympathetic nervous system when we essentially do nothing. It is also responsible for stimulation of “rest and digest” and “feed and breed” activities that occur when the body is at rest, especially after eating, including sexual arousal, lacrimation (tears), salivation, urination, digestion, and defecation. The parasympathetic nervous system is what makes us drift off to sleep every night. It is stimulated most when we relax deeply.
The war on our nervous system is essentially the overstimulation of our sympathetic nervous system along with an understimulation of the parasympathetic nervous system. When we stimulate only the sympathetic nervous system without activating the parasympathetic nervous system, we increase the probability of chemical imbalances in our brain from not having a healthy balanced lifestyle. Because of this, the vast majority of us are teetering on the edge of psychological suicide.