Oliver Sacks,M.D.writes that hallucinations are “percepts arising in the absence of any external reality – seeing things or hearing things that are not there.” They tend to be startling, mostly beyond conscious control; often detailed, colorful, bizarre, exotic, and meaningless. Some hallucinations are fleeting and some people live with hallucinations all their lives. People experiencing continuing hallucinations can usually accommodate them and differentiate them from reality, though hallucinations can interfere with activities such as driving.
The book excludes schizophrenia; that is a separate topic. These hallucinations are commonly associated with sensory deprivation (loss of sight or hearing) or monotony (long-distance truck drivers, sailors, and pilots; or marathon athletes); “mystagogic” drugs; or with illnesses Continue reading →