Hallucinations and Dreams

Hallucinations and Dreams

It is a common experience to feel that a dream landscape is physically “real” and then awaken to discover otherwise. This contrast is most vivid in attack dreams, from which the dreamer awakens to find that the monster (or whatever) is not really assaulting him or her. Such dream images are hallucinations, in the sense of having no corresponding physical reality. Many visual hallucinations also have a familiar, dreamlike quality, frequently resembling the hypnagogic experiences (those induced by drowsiness) one has just before falling off to sleep.

There is no clear boundary between dreams and hallucinations. Dreams are, for the most part, creations of the mind that do not depend upon immediate sensory input for their existence. The phenomena we call “hallucinations” are sometimes highly dependent upon sensory input (as in LSD hallucinations), but at other times seem to arise completely separate from sensory data.