FACTORS ASSOCIATED WITH INDIVIDUAL-DIFFERENCES IN CLINICAL MEASURES OF SPEECH RECOGNITION AMONG THE ELDERLY

In the present study, the speech-recognition performance of 50 subject s aged 63 to 83 years was measured for a wide range of materials (nons ense syllables, monosyllabic words, sentences) and listening condition s (presentation levels of 70 and 90 dB SPL, both in quiet and in a noi se background). In addition to complete audiologic evaluations, measur es of auditory processing (the Test of Basic Auditory Capabilities [TB AC], Watson, 1987) and cognitive function (Wechsler Adult intelligence Scale-Revised [WAIS-R], and the Wechsler Memory Scale-Revised [WMS-R] , Wechsler, 1981, 1987) were obtained from all subjects. Principal com ponent analyses were applied to each of the three sets of measures (sp eech-recognition, auditory, and cognitive) prior to examining associat ions among the sets using canonical analyses. Two principal components captured most of the systematic variation in performance sampled by t he set of 20 speech-recognition measures. Hearing loss emerged as the single largest factor associated with individual differences in speech -recognition performance among the elderly, accounting for 70-75% of t he total variance in speech-recognition performance, with the measures of auditory processing and cognitive function accounting for little o r no additional variance.