Also found in: Dictionary, Thesaurus, Medical, Legal.



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.


References in periodicals archive ?
Psychotic symptoms can include detachment from reality, hallucinations, delusions, disorganised thinking, and lack of motivation or emotion.
Assessments of the patients' auditory hallucinations were completed by researchers who were blind to which treatments patients had had.
Transcranial direct current stimulation (tDCS) is a non-invasion brain stimulation which has been suggested as a safe and promising treatment for antipsychotic-refractory auditory hallucinations in patients with schizophrenia.
The risk for relapse was particularly high when the hallucinations were primarily auditory, Dr.
We did not find a correlation between the ReHo value of the left precuneus and the severity of auditory hallucinations in the AVH patients.
It is also arguable that those who carry such a specific gene are more vulnerable to experience hallucinations when they abuse psychoactive substances and could get misdiagnosed as having schizophrenia, but hallucinations may cease to occur once they abstain from illicit drug abuse.
About 40% of those patients have Parkinson's disease psychosis, which is characterized by hallucinations and delusions, significantly burdens caregivers, and often leads to nursing home placement for Parkinson's patients.
Hallucinations and delusions can be profoundly disturbing and disabling, said Mitchell Mathis, M.
Although MES is not a "scary" disease, persistant hallucinations may disturb patients and affect their quality of life.
The delusions are something that the nurses are probably used to; it's just that the hallucinations can be a little different.
Hallucinations, by Oliver Sacks, hardback, 326 pp, $26.
The paintings and drawings in Korean-born artist Keunmin Lee's first solo show in the United States are all titled Refining Hallucinations--that is, they depict raw hallucinations, artistically refilled.