Individual consistency of hearing for speech across diverse listening conditions.

Abstract

Twenty speech tests each were administered twice to nine presbycuses and to nine individuals with other sensorineural hearing impairments. Ten of the 20 tests were received unaided and 10 with a hearing aid. Measures included spondee thresholds and discrimination for monosyllabic words in quiet and against competing sentences. Subjects tended to preserve their individual differences in scores on successive encounters with the same task, across the several spondee threshold tests, across the several discrimination tests and, to lesser degree, on comparisons between threshold tests and discrimination tests. Seven factors influenced performance. The weighting of these factors was partly a function of the distribution of the different tests and partly of the experimental variables. Comparison of results with factor analyses derived: from single runs of the same 20 tests administered to four pairs of groups including normals, conductives, presbycusics, and younger sensorineural, respectively, showed the total array of factors that emerged to vary somewhat with the group. Discrimination and sensitivity are two basic and relatively independent dimensions in hearing for speech as tested in this experiment. The other factors that appear against the framework of these two major dimensions depend upon the types of listener and the clusters of auditory task imposed.