Changes in the human brain and nervous system can result from intensive spiritual disciplines. The late Lee Sannella, M.D., author of Kundalini: Psychosis or Transcendence?, devoted many decades to the exploration of spiritual paths. "Kundalini" refers to energy coiled at the base of the spine which can rise up to the brain. Although Western science knows virtually nothing of this process, it has been described in detail in Eastern spiritual traditions.
"The peripheral signs and symptoms, and the descriptions which refer to the spinal cord and the accessory systems, whatever they are -- acupuncture or nadis -- are all derivative from the central event in the brain, which is a change itself, which represents psychophysiological change in the whole organism. This change then gives the person who has spiritual inclinations the equipment with which to more adequately join with the divine, which as you said is the original meaning of yoga."
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