Consonant recognition in quiet and in noise with aging among normal hearing listeners

Abstract

Consonant recognition in quiet and in noise was investigated as a function of age for essentially normal hearing listeners 21-68 years old, using the nonsense syllable test (NST) [Resnick et al., J. Acoust. Soc. Am. Suppl. 1 58, S114 (1975)]. The subjects audited the materials in quiet and at S/N ratios of +10 and +5 dB at their most comfortable listening levels (MCLs). The MCLs approximated conversational speech levels and were not significantly different between the age groups. The effects of age group, S/N condition (quiet, S/N +10, S/N +5) and NST subsets, and the S/N condition X subset interaction were all significant. Interactions involving the age factor were nonsignificant. Confusion matrices were similar across age groups, including the directions of errors between the most frequently confused phonemes. Also, the older subjects experienced performance decrements on the same features that were least accurately recognized by the younger subjects. The findings suggest that essentially normal older persons listening in quiet and in noise experience decreased consonant recognition ability, but that the nature of their phoneme confusions is similar to that of younger individuals. Even though the older subjects met the same selection criteria as did younger ones, there was an expected shift upward in auditory thresholds with age within these limits. Sensitivity at 8000 Hz was correlated with NST scores in noise when controlling for age, but the correlation between performance in noise and age was nonsignificant when controlling for the 8000-Hz threshold. These associations seem to implicate the phenomena underlying the increased 8000-Hz thresholds in the speech recognition problems of the elderly, and appear to support the concept of peripheral auditory deterioration with aging even among those with essentially normal hearing.

Age-related changes in consonant and sentence processing

“…Thus, our results replicate and extend the results of Gelfand et al, who found that aging produced a deterioration in consonant identification [15]. Aging significantly impaired consonant identification independent of age-related changes in audiometric thresholds, as in previous studies [4].…”

“…Confusion matrices for YNH subjects can be found in Woods et al [17]. Consistent with Gelfand et al's [15] observations, we found that consonant confusions were generally similar in the ONH and YNH groups. Table 2.…”

“…Previous studies have found age-related decrements in consonant identification when consonants are presented in nonsense syllables [8,12,15,18]. However, Dubno et al found no overall age-related changes in word recognition in audiometrically matched subjects ranging in age from 55 to 84 yr, suggesting that agerelated deficits in consonant identification may not be evident for lexically meaningful tokens [19].…”

“…For example, Gelfand et al used the City University of New York Nonsense Syllable Test to examine consonant discrimination in younger and older subjects with audiometric thresholds better than 25 dB at 250 to 8,000 Hz [15]. They found significant differences in performance between the younger (20-49 yr) and older (60-69 yr) subject groups despite similar patterns of consonant confusions.…”

Comparative intelligibility investigation of single-channel noise-reduction algorithms for Chinese, Japanese, and English

“…In the past several decades, many studies on speech perception in noise have been conducted to examine the effects of noise on speech recognition (Gelfand, 1986;Leek et al, 1987;Parikh and Loizou, 2005). Speech recognition generally declines in conditions wherein background interference is present.…”