Students of biology or medicine will likely be familiar with one of the largest single nerves in the body, called the vagus or “wandering” nerve. The nerve emerges from the brainstem and is one of the most important contributors to the parasympathetic nervous system, having important effects on the heart, lungs and intestines. The vagus causes the heart to slow, the intestines and kidneys to become more active and the bronchi to constrict. The vagus also has profound effects on metabolism: it has been known for more than a century that stimulating the base of the brain with opiates can cause the release of glucose from the liver, an effect mediated by the vagus. The nerve is also involved in the interaction of the immune system and the brain.
In recent years a technique called vagus nerve stimulation has been found to help some people with intractable epilepsy or treatment resistant depression. Many of the techniques of yogic or Taoist breathing as well as some techniques for inducing altered states of consciousness by eye movements or stimulating specific points on the ears all revolve around vagal stimulation. Some of these techniques have been shown to produce a sustained reduction in blood pressure.
I would like to focus upon the effects of the vagus on the heart. The heart is a physical location of an aspect of our emotional functioning. In Chinese Medicine it is known as the repository of Shen or Spirit. The heart is more than just a pump. It is also an important endocrine gland, and there is some evidence that it is also a sensory organ, with a sophisticated system for receiving and processing information. The neural network within the heart enables it to learn and remember. The heart constantly communicates with the brain, influencing key areas involved in perception, cognition and emotional processing.
You or someone you know may have had a baby. In which case you or they will have had intrauterine cardiac monitoring. Normally the baby’s heart rate varies from minute to minute. Some forty years ago it was discovered that if that variation stopped, it could be a harbinger of doom. Obstetricians knew this, but the rest of medicine forgot about the observation until 1991. Since then there has been enormous interest in the phenomenon of heart rate variability (HRV), because if it is lost, it can be a potent predictor of health problems. HRV reflects the tone in the autonomic nervous system. If this system becomes unbalanced, it can have effects on most of the major organs.
In the Ageless Wisdom the vagus is called our psychic antenna. We all have one, but not all of us have relearned how to use it. Many psychic stressors can produce physical effects via the vagus nerve. When doing acupuncture or energy healing it is very common for the patient to get a slowing of their heart rate and abdominal rumblings, which are sure signs of vagal activity. Psychics often get problems with their intestines while working with people, not from upset, but because they are exercising their skills.
There has been some interesting speculations about the role of the vagus in social behavior. Researchers have found that children with high levels of vagal activity are more resilient, can better handle stress, and get along better with peers than children with lower vagal tone.
There is a project underway at the University of California at Berkeley to see whether the vagus nerve might be the seat of compassion. Dacher Keltner is a professor of psychology and coeditor of Greater Good, a magazine about prosocial behaviors such as compassion and forgiveness. He has been examining the novel hypothesis that the vagus nerve is related to prosocial behavior such as caring for others and connecting with other people.
In his laboratory, Keltner has found that the level of activity in people’s vagus nerve correlates with how warm and friendly they are to other people. Interestingly, it also correlates with how likely they are to report having had a spiritual experience during a six-month follow-up period. Vagal tone is correlated with how much compassion people feel when they are presented with slides showing people in distress, such as starving children or people who are wincing or have a look of suffering on their faces.
Perhaps a key to compassion is to be found in the heart and the face.
Compassion is crucial to our survival. But compassion leavened with wisdom.
“Love and compassion are necessities, not luxuries. Without them humanity cannot survive.”
--The 14th Dalai Llama (a.k.a. Tenzin Gyatso, Tibetan Religious and Political Leader, 1935-)
“Out of compassion I destroy the darkness of their ignorance. From within them I light the lamp of wisdom and dispel all darkness from their lives."
--Bhagavad Gita
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