Illusion

An illusion is a sensory illusion, which is based on a misinterpretation of real sensory impressions. To put it more simply: The affected person perceives something that actually does not correspond to reality. Illusion is distinguished from hallucination because in illusion there is an actual source of stimulus. Causes of illusionary misperception are misinterpretations of things that actually exist. Thus, one may see a figure in a tree in the dark. Strong tiredness, states of intoxication or also a trance, as it is focused in the hypnosis, can cause among other things also illusions.