The effect of hypnotic anaesthesia on cortical responses

Abstract

Cortical evoked potentials were investigated in 9 subjects during and after hypnotic anesthesia had been suggested. An attempt was made to hypnotically induce deafness and was partially successful in 3 of the subjects. The results establish that no part of the sensory loss is due to attenuation of the afferent sensory impulses. The sensory loss may be mediated at a higher level and may be more related to a functional agnosia than anesthesia. In view of this, one may have specific objects not perceived due to lack of recognition. More knowledge about the neurophysiology of the process of object recognition, linking sensation to perception, might aid in understanding the mechanism by which hypnotic suggestion can render certain objects or sensations imperceptible.