Hypnosis is defined as an altered state of awareness in which you appear to be asleep or in a trance. Clinical hypnosis may be used to treat certain physical or psychological problems. For instance, it is frequently used to help patients pain. It is also used in a wide range of other conditions such as weight issues, speech disorders and addiction problems.

There is a debate about how hypnosis works. Some people believe that when you are hypnotised, you relax and concentrate more, and are more willing to listen to suggestions (for example giving up smoking.)

Even though you appear to be in a trance during hypnosis, you are not unconscious. You are still aware of your surroundings despite what many stage performers may claim during an entertaining show, you can't be made to do anything against your will. In fact brain tests performed on patients during hypnotism sessions have shown a high level of neurological activity.