Visual and auditory hallucinations: what exactly are they and what do they indicate?

Hallucinations. Hallucinations are false perceptions. That means-perceiving things that are not really there, but seem very real and vivid to the person experiencing it. Hallucinations may indicate: psychiatric disorder, such as schizophrenia, psychotic depression medical disorder, such as delirium substance abuse disorder mentally healthy people with significant visual loss can have visual hallucinations.