hallucinosis

   A term coined in or shortly before 1900, possibly by the German neurologist Carl Wernicke (1848-1904), to denote a mental state or disorder in which hallucinations feature prominently. The term hallucinosis has been variously defined as

   1) a mental state characterized by continual hallucinations,

   2) an abnormal condition or mental state characterized by hallucinations,

   3) a psychiatric disorder involving hallucinations,

   4) a syndrome, usually of organic origin, characterized by more or less persistent hallucinations,

   5) a transient hallucinatory state accompanied by a clear sensorium and/or proper insight into its nature, and

   6) a delusional state triggered by hallucinations (as in * hallucinosis phantastica).

   The French psychiatrist Henri Ey (1900-1977) follows his compatriot Henri Charles Jules Claude (1869-1946) and the German psychiatrist Paul Schröder (1873-1941) in characterizing hallucinosis as a hallucination, the false nature of which is recognized by the affected individual. Aware of the multiple connotations of the term hallucinosis, Ey proposes that it be replaced by *hallucinotic eidolia (éidolie hallucinosique). Wernicke, however, uses the term hallucinosis to denote the clinical picture of *paranoia hal-lucinatoria, as well as in the context of notions such as * acute hallucinosis, *chronic hallucinosis, and chronic hallucinosis of alcoholics (i.e. *alcoholic hallucinosis). Some additional examples of * hallucinosic syndromes described in the literature are * algohallucinosis, * brainstem auditory hallucinosis, *chronic tactile hallucinosis, *cocaine hallucinosis, *crepuscular hallucinosis, *experiential hallucinosis, *experiential thalamic hallucinosis, * functional hallucinosis, *hallucinosis phantastica, *narcotic hallucinosis, *organic hallucinosis, * peduncular hallucinosis, *persistent hallucinosis, and *syphilitic hallucinosis.

   References

   American Psychiatric Association (1975). A psychiatric glossary. Fourth revised edition. New York, NY: Basic Books.

   Berrios, G.E. (1985). Hallucinosis.In:Neu-robehavioural disorders. Edited by Frederiks, J.A.M. Amsterdam: Elsevier Science Publications.

   Plaut, F. (1913). Über Halluzinosen der Syphilitiker. Berlin: Verlag von Julius Thieme.

   Targowla, R., Leyritz, J. (1923). Sur l'hallucinose. Annales Médico-psychologiques, 81, 258-265.

   Wernicke, C. (1900). Grundriss der Psychiatrie. Leipzig: Verlag von Georg Thieme.