The words 'hypnosis' and 'hypnotism' both derive from the term "neuro-hypnotism"(nervous sleep) coined by the Scottish surgeon James Braid around 1841. Braid based his practice on that developed by Franz Mesmer and his followers ("Mesmerism" or "animal magnetism"), but differed inhis theory as to how the procedure worked.
Contrary to a popular misconception - that hypnosis is a form of unconsciousness resembling sleep - contemporary research suggests that it is actually awakeful state of focused attention and heightened suggestibility, with diminished peripheral awareness.
Skeptics point out the difficulty of distinguishing between hypnosis and theplacebo effect, proposing that hypnosis is so heavily reliant upon the effects of suggestion and belief that it would be hard to imagine how a credible placebo control could ever be devised for ahypnotism study.
It could be said that hypnotic suggestion is explicitly intended to make use of the placebo effect. For example, in 1994, Irving Kirsch proposed a definition of hypnosis as a "nondeceptivemega-placebo," a method which openly makes use of suggestion and employs methods to amplify its effects.
The earliest definition of hypnosis was given by Braid, who coined the term"hypnotism" as an abbreviation for "neuro-hypnotism", or nervous sleep, which he opposed to normal sleep, and defined as:
a peculiar condition of the nervous system, induced by a fixed and abstracted...