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East MEETS West
Scientific Research on the Effects of Yoga and Meditation

By Sat Bir Singh Khalsa, Ph.D
Issue : AquarianTimesGTYo 6/6/06

The history of East and West provides a fascinating study in the contrasting difference in perception and understanding of the Universe. In the East, the origin and development  of the inward spiritual practices of yoga and meditation  date back to the most ancient of times in the Indus Valley civilization, which ended around 1,500 B.C.E. Archaeological finds from the ruins of this culture in Pakistan and Northern India have revealed  artifacts strongly suggestive of the classic, cross-legged meditation/ yoga posture. The subsequent history of the East is deeply imbued with a reverence for the value of the most profound internal experiences— the quest for mastery of the spiritual world. In contrast, Western culture has been more influenced by the birth and development of the scientific method, which has been used to systematically and precisely uncover the underlying physical nature and laws of the Universe, leading to the astounding technology that pervades life in the West: the quest for mastery of the physical world.

Western Interest Begins

The story of research into the practice of yoga and meditation is one that is characterized by this East/West contrast. One  of the first interests in yoga came from the West after the European intrusion into India over the past three centuries.

Early reports of the ability of yoga practitioners to alter their physiological state to the extent that they could survive prolonged underground burial, withstand pain, and stop their heartbeat suggested that somehow the laws of biology were being circumvented. This of course raised eyebrows among Western scientists of the time. In 1851, N.C. Paul, a regimental surgeon in Benares who studied yoga for 35 years, published his  “Treatise on the Philosophy of Yoga” in which he analyzed, from the perspective of the Western science of the biology of gas exchange and metabolism, the cessation of breathing apparently involved in the yogic feat of underground burial and the relationship between frequency of breathing and yogic states of consciousness. Apparently, his book was ordered to be burned, an example of the bias against yoga research that persists in muted form even today. Ultimately, this kind of interest culminated in visits by Western physiologists to India in the middle of the 20th century to study not only these yogic feats, but also the claims of profound psychological experiences.

Perhaps the best example of this was the classic 1957 study entitled “Electro-physiological correlates of some Yogi exercises” by Basu Kumar Bagchi, a professor at the University of Michigan Medical Center (and close boyhood friend of Paramahansa Yogananda), and Marion A. Wenger, a psychologist at UCLA. These investigators spent five months traveling across India seeking out yoga masters and holy men. Using portable recording equipment they measured the physiological changes in these practitioners. The results of their study showed that yoga practitioners had extreme slowing of breath rate, the ability to slow the heart rate, and a deep relaxation of the autonomic nervous system.
These findings have stood the test of time and have been echoed and confirmed by the results of many subsequent research efforts in yoga and meditation.

Earlier Indian Research

Research on yoga by Indian investigators in Indian laboratories generally preceded that done by Westerners. In 1924, Swami Kuvalyananda began research on specific yoga techniques and founded a research institute and a yoga research journal, both of which are still active today. More recently, over the past three decades, Indian researchers have contributed to a substantial proportion of the literature of yoga research. A landmark EEG study in 1961 by B.K. Anand, G.S. Chinna, and B. Singh, at the prestigious All India Institute of Medical Sciences in Delhi, revealed the ability of yogic meditators to control sensory input to the nervous system while in deep meditation. Currently, one of the most active Indian yoga research groups is the Vivekananda Yoga Research Foundation in Bangalore, which has a large and active research institute that has been granted university status by the Indian government and is offering graduate degrees in yoga. The appearance and practice of yoga as a therapeutic intervention began in India in the early in the 20th century and continued through the 1960’s, when it was a popular therapy spawning the existence of “yogic hospitals” and precipitating the commissioning of a book on yoga therapy by the Indian government.

The 1960’s

The introduction of yoga and meditation to the West by Indian masters in the 1960’s generated a renewed interest among Western scientists, and most of the research in yoga and meditation has appeared since then. A landmark research project was the 1971 study by Herbert Benson and colleagues at Harvard Medical School that evaluated the physiological effects of Transcendental Meditation. Subsequently, Dr. Benson coined the term “relaxation response,” a distinct physiological change associated with reduction in arousal and metabolic rate elicited by many Eastern spiritual practices such as yoga and meditation. “Relaxation response” is essentially the opposite of the stress response.
His meditation research has continued since then and he has worked with a variety of meditation styles, including the practices of Tibetan meditators and Zen monks, and has contributed substantially to our knowledge of the physiology of the relaxation response and to its clinical benefits. His basic research has shown the ability of meditators to reduce metabolic rate and stress activation, while his clinical studies have shown the effectiveness of the relaxation response in treating disorders such as headache, hypertension, stress, anxiety, infertility, and chronic pain.

Types of Research

Research on yoga has included a broad range of study protocols which have examined a variety of changes in characteristics such as brain activity, mood, behavior, performance, hormone levels, blood chemistry, endurance, and flexibility. Furthermore, this work has been done on single techniques, full yoga routines, and yoga lifestyle interventions. In addition, this research has been carried out and evaluated in clinical trials on normal, healthy individuals as well as on patients with a variety of medical and psychiatric conditions such as depression, anxiety, asthma, hypertension, heart disease, and diabetes. Finally, a wide variety of yoga styles have also been evaluated, although the most commonly studied form has been the common form of hatha yoga. 

Single Technique Research

Examples of research on a single technique are studies on specific pranayama* practices. David Shannahoff-Khalsa, a long-time yoga researcher and Kundalini Yoga practitioner and instructor, began examining the naturally occurring alternating  pattern of the change in dominant airflow through the left and right nostrils. He observed that whichever nostril is dominant (more open to airflow) is associated with higher activity in the contralateral hemisphere of the brain (i.e. when you are breathing through the left nostril, the right hemisphere is activated and vice versa). Dr. Shannahoff-Khalsa, as well as researchers at the Vivekananda Yoga Research Foundation, among others, have taken the next step to also evaluate the yogic technique of forced breathing through alternate nostrils and the resulting contralateral and global effects on physiology, cognitive performance, and neuroendocrine function.

Lifestyle Research

On the other extreme is research using a comprehensive complete yoga lifestyle intervention, incorporating not only sets and routines of multiple yoga techniques but also yogic diet and fasting, conscious group living, and the study and specific application of yogic psychology and philosophy to ongoing medical or psychological conditions. One example of this is the 3HO Foundation SuperHealth program, which applied a complete residential Kundalini Yoga lifestyle intervention for addiction. In that program, participants with a variety of chronic substance abuse histories achieved significant improvement in their addictive behavior patterns and in their physical and psychological health. Another example of such a comprehensive lifestyle yoga intervention was conducted last summer at the Kripalu Yoga Center in Massachusetts with professional musicians attending the prestigious 8-week summer fellowship program of the Tanglewood Institute, in which I served as the research consultant. The participants took part in regular yoga and meditation classes, weekly group sessions using yogic-based counseling and problem-solving strategies, and also experienced the healthy meals and social atmosphere at the yoga center. At the end of the program they had less musical performance anxiety than fellow musicians who did not take the yoga program. Finally, therapeutic Kundalini Yoga programs for diabetics have been conducted by researchers of the Guru Ram Das Center for Medicine and Humanology.1 In these 8-week interventions diabetics were exposed to a regular series of yoga classes incorporating postures, breathing, meditation, stress management, psychological coping strategies, and carbohydrate intake management. Results of questionnaires completed by the participants showed improvements in depression, mood, stress, energy levels, quality of life, and relaxation. Similarly, Dr. Ramesh Bijlani of the All India Institute of Medical Sciences recently published a paper showing reductions in blood glucose and lipoproteins, risk factors for diabetes and heart disease, after a yoga lifestyle intervention.

Specific Targeted Research

In between these two extremes of yoga interventions is the use of specific sets or routines targeted at a specific physiological effect or for a specific clinical condition. In a study of a treatment of obsessive-compulsive disorder, Shannahoff-Khalsa used a 1-hour long Kundalini Yoga intervention including eight separate exercises, one of which was a 31-minute left nostril breathing meditation believed to be effective for psychiatric conditions. In that study, the patients assigned to the Kundalini Yoga intervention showed significant improvements over the course of three months of practice and greater improvements than a control group who practiced simple concentrative or mindfulness meditation without breathing or postures. Another example of this kind of intervention is in research I have been conducting evaluating a yoga treatment for insomnia. In a preliminary study, patients with chronic insomnia achieved significant improvements in their sleep after a daily 8-week treatment of a 45-minute Kundalini Yoga intervention that included a 31-minute breathing meditation called Shabad Kriya2 that is believed to be good for aiding healthy sleep. A larger randomized trial of this intervention is under way, which will also examine underlying physiological changes that take place over the course of the treatment.

Brain Imaging

A very exciting development in yoga and meditation research has been the incorporation of highly sophisticated brain imaging techniques. These studies use multi-million dollar hospital-based devices that are capable of localizing and quantifying the level of neural activity in discrete regions of the brain. Furthermore, brain activity can be measured from moment to moment as the research subject or patient is in the device performing a behavior or cognitive task. This capability is vastly superior in precision to the EEG, which previously was the primary measure of brain activity. In the year 2000, Sara Lazar, a Harvard colleague and friend who conducts research at the imaging facility at Massachusetts General Hospital, together with coauthors Gurucharan Singh Khalsa and Herbert Benson, published a study using the functional magnetic resonance imaging technique or fMRI. In that study, Dr. Lazar reported that a Kundalini Yoga meditation technique was capable of activating discrete brain regions distinctly different from those involved in a control task. She concluded that “the practice of meditation activates neural structures involved in attention and control of the autonomic nervous system,” a conclusion consistent with the pioneer work of Bagchi and Wenger decades earlier. Similarly, Dr. Dharma Singh Khalsa conducted a research study using another brain imaging technique to demonstrate that 11 experienced meditators  practicing a Kundalini Yoga meditation called  Kirtan Kriya3 showed changes in specific brain regions believed to be associated with  spiritual experience.

Mindfulness Meditation

A significant initiative in meditation research has been on the study of mindfulness meditation or Vipassana from the Buddhist tradition. This technique has become very popular over the recent past, and the Mindfulness Based Stress Reduction program inspired by Jon Kabat-Zinn is being widely used for a variety of medical and psychological conditions. Research on mindfulness meditation has been supported vigorously by the Dalai Lama, who has organized public and private meetings with scientists inviting them to participate in meditation research. He recently gave a major address to the annual meeting of the Society for Neuroscience (attended by 14,000 out of the almost 35,000 meeting attendees) in Washington, D.C., which generated significant media attention. Some of their ongoing research has focused on brain imaging studies of Buddhist monks and longterm practitioners. Recently, Dr. Lazar published a study that showed that long-term practitioners of mindfulness meditation showed changes in brain volume in regions known to be associated with control of attention and that meditators
appeared to be spared the known reductions in brain volume associated with aging.

An interesting proposal presented by the mindfulness researchers has been to use the expert meditation skills of Buddhists as a scientific instrument. Since lifelong practitioners of Buddhist meditation have strived to acquire a deep understanding of the workings of the mind and the subconscious, it is conceivable that this skill can be used in novel and creative experimental designs to gain insight into how meditation works and how aberrant psychology might develop.

Research Turns Full Circle

Interestingly, this idea brings us full circle from the beginnings of research in yoga and meditation, when Western scientific technology was applied to unravel the meditation experience, to the present day where Eastern meditation technology is itself being proposed as an experimental tool.

The burgeoning public interest in yoga and meditation and its use for alleviating clinical conditions has undoubtedly contributed to the recent increase in yoga and meditation research. This interest, together with the use of modern technological approaches that can directly observe the effects of these practices on brain function, suggest that there is much more to come in the field of research in
yoga and meditation.

Sat Bir Singh is Assistant Professor of Medicine at Harvard Medical School. He has been practicing the Kundalini Yoga lifestyle for over 30 years and is a certified Kundalini Yoga instructor.

* See Glossary, p. 45.

  1. A foundation based in Espanola, New Mexico, whose mission is to provide health education and instruction in yoga and meditation to persons with chronic or life-threatening illness, to train health professionals to use these techniques in their practice, and to conduct  research into the medical effects of Kundalini Yoga. Visit
  2. Shabad Kriya can be found in the Kundalini Meditation Manual, available from
Kirtan Kriya can be found at  and