Auditory Perceptibility: Acuity and Dominance

determination of gross auditory perceptibility of value to clinicians, generally. It is not demanded of the clinical psychologist that he compete with the aurist, but if a correct diagnosis is to be made he must establish the degree of auditory perceptibility3 and recognize the handicaps of reduced auditory acuity to effect necessary school adjustments and to stress the need for medical care. The use of the " cricket," tuning fork, Galton Whistle and the other apparatus usually employed do not give an adequate picture of hearing status. Deafness to the psychologist must be considered in three categories first, total deafness; second, partial deafness in which further involvement is not imminent; and third, progressive deafness. Behavior changes, lack of normal speech development, etc., accompanying deafness are easily observable, and sometimes are the first cue to hearing difficulty. Especially is the problem of hearing crucial in the differential diagnosis of speech defects not only in those lacking speech entirely, but in profound stammering, mutilations, monotone, foreign accent and dialects. Speech, an instinctive urge, displays itself when there is ideational content and an integrated neuro-muscular mechanism capable of producing the necessary performance pattern. It will be observed that deafness is the first possible factor to consider in