Meditation is huge in the US - 10 million American adults now say they practice it in some form regularly. It is used to restore balance in the face of psychiatric problems such as depression and anxiety.

M Hyland, Professor of Health Psychology at Plymouth University states "if you look at a spot on the other side of the room and stop talking and thinking you will be meditating. It's like cleaning your personal windscreen; you get to see things more clearly."

The brain undergoes subtle changes during deep meditation. In India, Yogi's can meditate into a trance so deep that they do not react when hot test tubes are pressed against their arms. In Japan, Zen meditators can be so focussed on the moment that they do not adjust to the sound of a ticking clock. At Harvard Medical School studies on transcendental meditators found that when they meditated they used 17% less oxygen, lowered their heart rate by 3 beats per minute and increased their theta brain waves - the ones appearing right before falling asleep - without slipping into the brain wave pattern of actual sleep. Brain scans suggest that it may be rewiring brains to reduce stress. Tests using the most sophisticated imaging techniques suggest that it can reset the brain, changing the point at which a traffic jam ,for instance, sets the blood boiling.