Hypnose et conscience

Abstract

Hypnotic-like behavior has been reported from the dawn of history. The early origins are shrouded in mystery and magic; but Franz Anton Mesmer, an Austrian physician, conducted his therapeutic sessions under the name of “animal magnestism”. He proposed a theory that the “magnetic” influence could be transfered by iron bars. However a committee of leading scientists of the day showed that the “magnetic” influence could be transfered as well by wooden rods as by iron bars and that influence upon the patient was a result of imagination. Mesmer was obviously wrong in his theory, but he was the first attempting to use modern physical science to replace some of the superstition of his day. This in turn became opposition between supporters of physiological theories and those of psychological theories. Salpêtrière, with Charcot, saw a pathological state in hypnosis, an artificial hysterical neurosis. On the other hand, the Nancy school of thought, represented by Bernheim, Liébault and Liégeois, suggested that it was a normal psychological phenomenon. The fight between the two schools was very bitter. Other theories initially inspired by the Pavlov school of thought came to light; these were replaced by those inspired by experimental psychology and a third psychoanalytic theory became predominant. A description of the hypnotic state revealed the reality and non-reality of the hypnotic state. This was the outcome of functional neuro-imaging techniques that are currently revolutionising our knowledge of cerebral functioning and research in the area of cognitive neuroscience allows questions about consciousness and its neurobiological substrate to be asked. Research into hypnosis requires a distinction to be made between “the state of consciousness” and “conscious content”. Various functional neuro-imaging studies are reported investigating the area of “neurophenomenology” in the hypnotic process.