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perceptions originating in the absence of a real object in mental illness and some infectious diseases, poisonings, brain traumas, severe emotional shocks, and so on.

To the patients, hallucinations are actual perceptions and not something imagined. Distinctions are made between several types of hallucinations: auditory (voices, calling of one’s name, noises, various kinds of sounds), visual (visions of people, dead persons, animals, insects, monsters, pictures, and events), olfactory (odors of rot, kerosine, perfumes, etc.), and tactile (sensations of insects on the skin, moisture, and blowing), as well as so-called general-sensation hallucinations (some object or animal is present and moving in the abdominal cavity or chest) and extracampal hallucinations (the patient “sees” outside his field of vision a person, persecutor, etc.). Some hallucinations have bright sensory coloration, imagery, and persuasiveness. They are projected outward and may be indistinguishable from real perceptions. Such hallucinations are called genuine. Other hallucinations are perceived by the inner hearing or vision of the patient, are localized in the internal field of consciousness, and are accompanied by a feeling of “accomplishment” and by the influence of some force that causes him to have visions, “loud” thoughts, and so on. These are pseudohallucinations, described at the end of the 19th century by the Russian psychiatrist V. Kh. Kandinskii.

Under the influence of hallucinations which have an imperative, command character, the patient may perform acts that are dangerous to those around him and to his own health and life. Hallucinations are an important and characteristic symptom of many mental illnesses. The pathophysiological nature of hallucinations has not been completely elucidated. Treatment is directed toward eliminating the main disease.


Popov, E. A. Materialy k klinike i patogenezu galliutsinatsii. Kharkov, 1941.
Giliarovskii, V. A. Uchenie o galliutsinatsiiakh. Moscow, 1949.


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