English

Noun

nocturnal delirium ‎(plural nocturnal deliria)

1. (medicine, psychology, psychiatry) A state of agitation or confusion, especially in elderly patients suffering from Alzheimer's disease or other forms of dementia, which begins daily at nightfall and which is alleviated by daylight.
   • 1941, D. Ewen Cameron MD, “Studies in senile nocturnal delirium”, in Psychiatric Quarterly, volume 15, number 1, page 51:

     Nocturnal delirium of the senile patient is primarily due to the fact that the severe retention defect, and more particularly the greatly accelerated secondary elaboration (Cameron, 1940) found in senile patients, does not permit of the preservation of the spatial image after darkness has interfered with direct visualization.

   • 1996, Piero Camporesi, Bread of Dreams: Food and Fantasy in Early Modern Europe, page 128:

     The nocturnal deliria were piled together with the daytime intoxications and obsessions in order to build a particularly adaptable dream machine, which still awaits a visit from social psychoanalysis in order to penetrate a bit more lucidly into the ancien régime's intricate labryinth of dreams.

   • 2011, Augusto Caraceni, Delirium: Acute Confusional States in Palliative Medicine, page 56:

     Preliminary observations by means of motor activity recordings made it possible to classify demented patients with delirium into different groups according to their motor activity, e.g. nocturnal delirium type, wandering type, hypoboulic type, and lying-down type (Honma et a., 1998).

Synonyms

• sundowner syndrome
• sundowning