Hypnosis: a state of human consciousness involving focused attention and reduced peripheral awareness and an enhanced capacity to respond to suggestion. Theories explaining what occurs during hypnosis fall into two groups. Altered state theories see hypnosis as an altered state of mind or trance, marked by a level of awareness different from the ordinary conscious state. In contrast, nonstate theories see hypnosis as a form of imaginative role enactment. During hypnosis, a person is said to have heightened focus and concentration. The person can concentrate intensely on a specific thought or memory, while blocking out sources of distraction.