Nonvibratory tinnitus; factors underlying subaudible and audible irritations.

FOUR YEARS AGO, before the American Laryngological, Rhinological and Otological Society, Inc., I read a paper entitled "The Control of Head Noises." 1 The opening paragraph in that paper seems appropriate for repetition here. It stated: If one disregards the auditory hallucinations occurring in organic diseases of the brain and in the psychoses, there are two kinds of tinnitus: (1) vibratory, caused by actual autogenous vibrations reaching the ear from any part of the body, and (2) nonvibratory, caused by biochemical irritation of the auditory neural mechanism. 2 Either of these two kinds of tinnitus may be superimposed on the other, in which case either one with sufficient intensity and proper frequency can diminish or increase the loudness and change the timber and therefore the degree of annoyance of the other. In the present paper I shall deal with the second or nonvibratory type of tinnitus and shall discuss means for exploring