|
|
Science of Meditation
Meditation has a wide range of scientifically measurable effects. In 1988 Michael Murphy and Steven Donovan, of the Esalen Institute, published The Physical and Psychological Effects of Meditation and reported 1,253 scientific and literary studies on meditation going back to 1931. When they published a second edition in 1996, they had added about 400 more studies. During those eight years, they reported, growth in research had been "nothing short of spectacular," with investigations moving beyond the gross physiology to subtle changes in biochemistry and voluntary control of internal states. The studies don’t all line up perfectly in support of meditation’s effectiveness. They create debate and raise questions. But, that is the way of science in every area it explores.
It takes a lot of money and time to study anything at the level proper for professional publication. The amazing array of studies visible even in the table of contents of Murphy and Donovan’s book tells a significant story. There could not be such a rich set of published studies had there not first been a long, persistent history of meditation’s effects, felt outside of science, by people practicing a wide variety of meditative styles. Each study began with an intriguing suggestion springing out of direct experience.
Listing all that we now know or suspect happens during a natural style meditation would be daunting. So, here are some highlights that I enjoy:
Physiologically, the meditative function brings reduced tension, greater blood flow, reduced blood pressure, slower breathing, reduced consumption of oxygen (a measure of metabolic level), increased brain activity in the frequencies associated with relaxation and happiness (alpha and theta waves). Chemicals normally associated with stress (blood lactate and the hormone cortisol) are reduced, and calming hormones associated with wellbeing (melatonin and serotonin) are increased.
Indeed, meditation seems to be uniquely capable of processing the dangerously-common stress hormone, cortisol. One study showed declines of 25% in long-term meditators during their sittings. Short-term meditators showed small declines, and no change was seen in the control groups doing rest and relaxation (Murphy and Donovan 1996:65). Cortisol is an adrenal hormone that is found in extremely high levels in people with pain and is associated with the fight-or-flight response, that stress-readiness condition urgently needed during periods of acute physical danger. Cortisol is a damaging chemical to leave lingering in the bloodstream. It can be cleared out when the event that triggered it can be addressed directly with an explosion of physical action (fighting or running away); otherwise, it lingers and corrodes the body. Dharma Singh Khalsa, M.D., a previous graduate student of Benson and author of Meditation as Medicine says that the stress-induced overproduction of stimulating hormones, such as cortisol and adrenaline, "accelerates the aging process, and is a major risk factor not only in Alzheimer’s disease but also in the far more common condition of age-associated memory disorder" . He also favors meditation as a way of clearing cortisol from the bloodstream.
0 comments:
Post a Comment