Definition: A false sensory perception that a person cannot distinguish from reality, but that is not connected to a real stimulus in the world outside the sufferer's mind. In schizophrenia, auditory hallucinations are most common, closely followed by visual hallucinations. Hallucinations of smell, taste and touch are also possible.
Examples: Joy's persistent visual hallucination of being followed by small children explained why she always held the door open for a few moments before stepping through.