Hypnosis is a state of human consciousness involving focused attention and reduced peripheral awareness and an enhanced capacity to respond to suggestion. Although hypnosis has been controversial, most clinicians now agree it can be a powerful, effective therapeutic technique for a wide range of conditions, including pain, anxiety and mood disorders. The hypnotic induction is an extended initial suggestion for using one's imagination, and may contain further elaborations of the introduction. A hypnotic procedure is used to encourage and evaluate responses to suggestions. When using hypnosis, one person is guided by another to respond to suggestions for changes in subjective experience, alterations in perception, sensation, emotion, thought or behavior. The mind that opens to a new idea never returns to its original size.