Perceptual disorders occur in all sensory modalities. It occurs when there is disruption in perception perhaps caused by physical or mental disorders or toxins etc. They include misinterpretations and distortions of environmental stimuli, as well as selfgenerated hallucinations. It is more commonly evident in schizophrenia(as a part of first rank symptoms), organic conditions and rarely in mood disorders. People with the disorder may hear voices or see things that aren’t there. The voices give instruction to some patient who may or may not feel obliged to carry them out . In some cases the voices talk about the person in the third person and may give a running commentary on his action which is often troublesome. Hallucinatory voices vary in quality, ranging from those which are clear to those which are extremely vague and which patients cannot describe in any way. One special type of hallucination, which is characteristic of schizophrenia, is thought echo that is hearing one’s own thoughts being spoken aloud which is called sonorization. The pathogenesis of these phenomena is largely unknown, but disturbances in specific sensory modalities have implications from the perspectives of diagnosis as well as management. However, few etiologies have been identified responsible for causing hallucinations namely sensory deprivation,hallucinogens and drugs,insomnia,sensory defects, stress, emotions, toxins, disorders of central nervous systemand neurotransmitter imbalance.

Keywords: Charles Bonnet Syndrome; Culture, Hallucination; Perceptual Disorder; Schizophrenia.