Illusion is:
Illusion is an abnormal perception caused by a sensory misinterpretation of actual stimulus, sometimes precipitated by strong emotion, e.g. fear provoking a person to imagine they have seen an intruder in the shadows. REF : Oxford text book of psychiatry 3rd Ed.
A false unshaken belief not keeping one's sociaocultural background
Perception without stimuli
Abnormal perception by a sensory misinterpretation of actual stimulus
Fear of closed spaces
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