Akademik

   The term twilight state is used to denote a prolonged state of clouded or narrowed consciousness during which the affected individual is virtually unaware of his or her environment, and typically experiences "visual and/or "auditory hallucinations. These hallucinations may also be " compound or "panoramic in nature, in the latter case replacing the entire extracorporeal environment as perceived through the senses. Twilight states tend to be accompanied by irrational motor behaviour such as undressing in public, aimless wandering, running away, or committing acts of violence. They can last for a period of days to weeks, although twilight states lasting up to a year have been described as well. They tend to begin and end abruptly, and to be followed by amnesia for the entire episode, and/or a subjective sense of having been dreaming. When the clinical picture is dominated by hallucinations and * illusions, the term * hallucinatory twilight state is used. Using the supposed etiology of the syndrome as a guiding principle, twilight states are traditionally divided into organic and psychogenic twilight states. Some examples of organic twilight states are those occurring in the context of complex partial seizures affecting the temporal lobe (i.e. epileptic or episodic twilight states), fever, uraemia, eclampsia, and intoxication with alcohol (i.e. alcoholic twilight states) or other substances. Some examples of psychogenic twilight states are those occurring in the context of * dissociation (i.e. dissociative or hysterical twilight states), the Ganser syndrome or mood disorders. Within the context of this dichotomous classification, the status of twilight states occurring in association with catatonia would seem to be open to debate. In 1926 the German neuropsy-chiatrist Karl Kleist (1879-1960) devised an elaborate classification of twilight states. An extreme variant of the twilight state occurring in Haiti, and described in 1985 by the Canadian anthropologist and ethnobotanist Edmund Wade Davis (b. 1953), is called zombification. Reportedly, this type of twilight state can be evoked with the aid of a potion containing tetrodotoxin or alkaloids such as datura. Conceptually as well as phe-nomenologically, the twilight state would seem to lie on a continuum with conditions such as dissociation, hysteria, fugue, * hallucinatory epilepsy, postictal confusion, * alcoholic hallucinosis, and * delirium.

   References

   Davis, W. (1985). The serpent and the rainbow. New York, NY: Simon & Schuster.

   Jahrreiss, W. (1928). Dämmerzustände.In: Handbuch der Geisteskrankheiten. Erster Band. Allgemeiner TeilI. Herausgegeben von Bumke, O. Berlin: Verlag von Julius Springer.

   Kleist, K. (1926). Episodische Dämmerzustände. Ein Beitrag zur Kenntniss der konstitutionellen Geistesstörungen. Leipzig: Georg Thieme Verlag.

   Suzuki, H., Tsukamoto, C., Nakano, Y., Aoki, S., Kuroda, S. (1998). Delusions and hallucinations in patients with borderline personality disorder. Psychiatry and Clinical Neurosciences, 52, 605-610.