Bleuler, in 1924,1 wrote of delirium tremens, . . . "one . . . observes elementary hallucinations, especially in the form of reports and shots, but also buzzing, roaring, hissing, etc. . . ." Of alcoholic hallucinosis he said, ". . . especially in the beginning one seldom fails to note sounds, such a buzzing, snapping of gun triggers, striking of rifle bullets, cracking, and sounds of horses' hoofs. . . ." By the term "elementary hallucinations" in the acoustic field he means "the simple noises such as murmurs, knocks, and shooting."
It has been generally held that there is no basic difference between elementary and formed hallucinations2,3 and that the former evolve into the latter as the psychosis unfolds.3 Gross and his co-workers,4,5 in the first systematic studies of the buzzing, humming, and similar noises often experienced in acute alcohol withdrawal psychoses, concluded that these phenomena are not hallucinations but examples of
Saravay SM, Pardes H. Auditory Elementary Hallucinations in Alcohol Withdrawal Psychosis. Arch Gen Psychiatry. 1967;16(6):652-658. doi:10.1001/archpsyc.1967.01730240008002