By using a variety of techniques, self-inducing the mystical altered state of consciousness has become a very popular activity, even for Christians. Amazingly, the technique has found numerous adherents within the Missouri Synod. In 1920's, Dr. Hans Berger, a German psychiatrist, uncovered some interesting insights about the activity of the brain during various stages of human consciousness. In the alpha zone, the human brain is in a state of receptivity.
Images freely flow through the imagination.
The critical, rational mind, as Jose Silva puts in, is on the back burner and the imaginative mind is up-front. It is important to point out that entering the alpha zone is a natural human condition and is experienced by everyone prior to falling asleep. We have all sensed the free flow of images that pass through the mind immediately before sleep. This is natural. This is alpha.