jenny cares 

From Forget It! A Biochemical Pathway For Blocking Your Worst Fears?:

A receptor for glutamate, the most prominent neurotransmitter in the brain, plays a key role in the process of "unlearning"...

..."Most people agree that failure to 'unlearn' is a hallmark of post-traumatic stress disorders and if we had a drug that affects this gene it could help soldiers coming back from the war to 'unlearn' their fear memories." 

Yoga

After the tsunami ripped through Southeast Asia in 2004 came a tidal wave of psychic devastation... depression and posttraumatic stress ravaged many residents of coastal villages from India to Indonesia -providing a living laboratory for testing the most powerful cures available.

What wound up providing the best help to some of the most afflicted refugees? Yoga.

As a professor of psychiatry at New York Medical College who studies the effects of yoga on posttraumatic stress, Patricia Gerbarg seized the opportunity to test whether it could help tsunami survivors in India. To one group of 60 victims she gave a four-day yoga breathing course. Another group of 60 survivors was given the yoga course along with psychological counseling. A third group served as controls.

All the yoga users experienced a huge drop in scores for posttraumatic stress disorder and depression after just four days. And the effect was so persistent that Gerbarg and her team introduced yoga to those in the control group too. Counseling provided no added benefits over the yoga training alone.

While some forms of yoga have long been shown to reduce hypertension, cholesterol levels, and other signs of physiological stress, the effects of the ancient practice on psychological stress have been less studied. But a slew of research published in peer-reviewed journals in the U.S., Europe, and India is documenting the ability of yoga to decrease mood disturbance, reduce psychic stress and anxiety, and reduce PTSD symptoms.

Effects have been seen within days of initiating instruction, and have been documented up to six months after a course of yoga training.  

You don't have to weather a natural disaster or receive a clinical diagnosis to benefit from yoga, says Lorenzo Cohen, director of the Integrative Medicine Program at the University of Texas M.D. Anderson Cancer Center in Houston.
Calling it "the quintessential mind-body practice," Cohen predicts that yoga "can and will be shown to be helpful for managing the stress and mild anxiety we all experience in daily living." 

A group of healthy senior citizens in Oregon embodies Cohen's claims. They experienced improved energy and a greater sense of well-being after six months of yoga training. The study was particularly valuable because it compared the yoga group with seniors engaging in walking exercise classes. The non-yoga exercisers reported no such benefit. 

In her yoga course, Gerbarg trains trauma sufferers in four types of yogic breathing that range from focusing on slow, complete exhalation to taking 30 breaths a minute... and ...found that yogic breathing physiologically affects the nervous system to produce profound changes in emotional states.

It acts via the vagus nerve—the "rest and digest," or calming, pathway of the autonomic nervous system extending from brain stem to abdomen; when activated, it slows down breathing and heart rate and increases intestinal activity. .

It not only carries signals from brain to body but ferries signals from the body back to the brain. "Your breathing pattern changes with emotional reactions to things," Gerbarg says. "Well, it goes both ways: If you change your breathing pattern, you can change your emotions." Lynn Waelde, a psychologist at the Pacific Graduate School of Psychology and a yoga teacher, explains yoga's mind-body benefits in more metaphorical terms. "When we teach yoga, we teach people to let go of physical tensions," she says. "When you sit them in a chair in meditation, they get it. It's an easy step to see how you can breathe and focus on emotional or mental tension and let it go."

Could yoga save the world?
It improves fitness, it doesn't cost anything, it has minimal side effects, it acts quickly, and the benefits endure. The advantages are especially important when applied on a large scale to impoverished people. Gerbarg and Cohen believe the value of yoga is just beginning to be documented. "We're in the early phases of something very exciting, and there's a lot more to learn about it," Gerbarg says.

"This is not something you need to religiously incorporate into your daily life and do for years before you start to feel the benefits."