Home > Encyclopedia of Psychology > Hypnosis

A temporary narrowing of conscious awareness.

Practiced since ancient times, hypnosis or hypnotism remains difficult to define accurately and completely. Although the word hypnosis comes from the Greek word hypnos, for sleep, hypnosis is actually an intense state of concentration.

There are three degrees of hypnosis. Under light hypnosis, the subject becomes sleepy and follows simple directions; under deep hypnosis, the person experiences dulling of sensory perception, similar to that of anesthesia. Under deep hypnosis, the subject can move about, open his or her eyes, and can even undergo medical procedures with no additional anesthetic. Magicians and illusionists use deep hypnosis to make a subject behave in unusual ways, such as to suspend the...