Age differences for stop-consonant and vowel perception in adults

The purpose of this study was to determine the role of static, dynamic, and integrated cues for perception in three adult age groups, and to determine whether age has an effect on both consonant and vowel perception, as predi cted by the "age-related deficit hypothesis." Eight adult subjects in each of the age ranges of young (ages 20-26), middle aged (ages 52-59), and old (ages 70-76) listened to synthesized syllables composed of combinations of [b d g] and [i u a], The synthesis parameters included manipulations of the following stimulus variables: formant transition (moving or straight), noi se burst (present or absent), and voicing duration (10, 30, or 46 ms). Vowe l perception was high across all conditions. and there were no significant differences among age groups. Consonant identification showed a definite ef fect of age. Young and middle-aged adults were significantly better than ol der adults at identifying consonants from secondary cues only. Older adults relied on the integration of static and dynamic cues to a greater extent t han younger and middle-aged listeners for identification of place of articu lation of stop consonants. Duration facilitated correct stop-consonant iden tification in the young and middle-aged groups for the no-burst conditions, but not in the old group. These findings for the duration of stop-consonan t transitions indicate reductions in processing speed with acre. In general , the results did not support the acre-related deficit hypothesis for adult identification of vowels and consonants from dynamic spectral cues. (C) 20 01 Acoustical Society of America.