Thanks to Sat Bir Khalsa for this much-needed review of research on yoga, in a format fit for public consumption. What a relief that he includes research spanning the many dimensions of the yoga path - meditation, poses, breathing practices, chanting, etc. - not just a flattened, overly-simplified view of yoga as physical practice. His comment about William Broad's provocative (sensationalized) book on the science of yoga is quite thoughtful. It's also interesting to read his personal journey into yoga research. Overall, a quick and interesting read for anyone considering yoga in a therapeutic context.

Can yoga help reduce the stress that makes you look and feel older than your years? Does yoga help elevate your mood and make you mentally sharper? Will meditation enhance your spiritual outlook or give you a sense of peace and calm? As a Harvard neuro-scientist and a yoga practitioner for more than 4o years, I'm pleased to tell you the answers are a resounding "yes." As nearly everyone knows, life can be stressful—and it's only getting worse. In the American Psychological Association's "Stress in America" survey, nearly half of the more than 1,000 respondents reported having more stress in their lives than in the past five years.

Is avoiding all stress possible? Not really. But we can learn ways to reduce or manage our perceived stress and related anxiety through yoga and other contemplative mind-body practices, which have been scientifically proven to change our brain behavior and chemistry and, thereby, reduce our stress. Although there are a few prescription medications that have been used for stress, practicing yoga and meditation are simple and much more desirable ways to cope with stress because they address the root of the problem and do so without any negative side effects—in fact, they often have a few positive side effects.

In this book, you will learn how yoga helps build a resilience to stress so you are able to accept it, deal with it, and get on with your life. After brief sessions only 10 to 15 minutes long, you will start noticing positive physical and mental changes. If you practice regularly, you will experience positive changes in both your body and your attitudes and perceptions, which will support you in moving towards a healthier lifestyle. I will explain why yoga helps us get a deeper, more restorative sleep, which is crucial to keeping our minds and bodies vigorous as we age. When you add proper nutrition and physical exercise to this equation, all this can lead to life-altering behavior and improved mental and physical fitness.

And while yoga helps rejuvenate our bodies and minds, you can also benefit from an elevation of mood, quality of life and even a deeper sense of spirituality. Practicing yoga ultimately allows you to perceive the world in a more relaxed, non-judgmental, positive way, countering the stress reactivity that sends your nervous system into overdrive. Yoga might not literally be a fountain of youth, but it can lead to a transformative experience that will improve your quality of life, your sense of well-being and your outlook on life.

YOUR BRAIN ON YOGA explains how yoga and meditation can change your brain and, thereby, your life. The way you think about yoga probably depends on your age. In the sixties, yoga was linked to the counterculture and to experimenting musicians like the Beatles. Those who were born in the seventies and beyond will likely picture Madonna's "yoga arms" and soccer moms—their lithe and Lululemon-clad bodies twisting into seemingly impossible positions.

But yoga is far more than the images we see in the media. In fact, at its very essence, it encompasses a range of practices, from sitting quietly to a sweat-producing, heart-pumping physical exercise. But you don't need to begin a yoga practice with the goal of performing gravity- defying positions. The word yoga is translated from the Sanskrit word "yug" or "yuj," which means "to yoke" or "union" and traditional yoga practice had the goal of achieving a unitive state of mind in which there is balance between mind and body.

If you are new to yoga, you will find many different types to choose from, but all traditional or classical yoga involves not only physical postures and exercises, but also breath control techniques, deep relaxation techniques, meditation and concentration practices, and the cultivation of mindfulness or awareness. For centuries yogis and saints have understood the mind-body connection, and now today's scientists are realizing its potential within medicine. To some traditional Western physicians, yoga is just another type of workout to be taught at gyms around the country along with spinning and aerobics. But yoga is far more than that.

This book reveals compelling neuro-scientific evidence that demonstrates the variety of ways yoga can change your brain, including brain activity, biochemical and even structural changes. Brain scans (fMRIs), which show pictures of our neural patterns, have demonstrated the positive changes that take place in the brains of people who practice meditation. These neural imaging studies reveal how regions of the brain that are responsible for such fundamental human traits as attention, body awareness, higher-level cognitive function and self-perception grow and become stronger—in some cases the transformation occurs immediately.

Neuroscientists are only beginning to understand yoga's role in preventive medicine, and its ability to treat a range of maladies. I will tell you about some of the groundbreaking studies that I am conducting at Brigham and Women's Hospital/Harvard Medical School and other research institutions, some of which are funded by the National Institute of Health's National Center for Complementary and Alternative Medicine (NCCAM) and the Institute for Extraordinary Living of the Kripalu Center for Yoga and Health. Many ongoing yoga research studies internationally are examining yoga's role in improving mood, reducing perceived stress, decreasing heart rate and blood pressure, increasing lung capacity, improving muscle relaxation and body composition, and helping treat conditions, including anxiety, depression, and insomnia.