Indiana University, Bloomington, Indiana, USA.
J Speech Lang Hear Res. 2012 Apr;55(2):487-99. doi: 10.1044/1092-4388(2011/11-0102). Epub 2012 Jan 3.
Temporal order abilities decrease with age. Declining temporal processing abilities may influence the identification of rapid vowel sequences. Identification patterns for asynchronous vowel pairs were explored across the life span.
Young, middle-aged, and older listeners completed temporal order tasks for pairs of 70-ms and 40-ms vowel stimuli. For a given vowel duration, naturally spoken vowels were equated for duration, intensity, and fundamental frequency. Listeners completed monaural and dichotic temporal order tasks that involved identifying the vowel pair in the correct order. The stimulus onset asynchrony that yielded 50% accuracy for identifying the vowel pair in the correct order was used to equate performance among listeners. Vowel identification response patterns were determined at this stimulus onset asynchrony threshold.
Vowel identification patterns were largely consistent across age groups. Older listeners were influenced by the order of certain vowel pairs. Not all vowel pairs were identified equally well. Vowel dominance patterns were also observed, with /a/ being identified most accurately for the vowel pairs tested. Formant dynamics explained, in part, identification and confusion patterns.
Vowel identification accuracy patterns were reasonably similar across the life span, regardless of presentation mode, vowel duration, or effect of considerable stimulus exposure. Large effects of vowel order were observed, particularly for older listeners.
时间顺序能力随年龄增长而下降。时间处理能力的下降可能会影响对快速元音序列的识别。本研究探索了整个生命周期中异步元音对的识别模式。
年轻、中年和老年听众完成了时长为 70ms 和 40ms 的元音对的时间顺序任务。对于给定的元音时长，自然发音的元音在时长、强度和基频方面进行了匹配。听众完成了单耳和双耳时间顺序任务，需要正确识别元音对的顺序。用于识别正确顺序的元音对的刺激起始时相差 50%的准确率，用于在听众之间进行表现的匹配。在这个刺激起始时相差阈值确定了元音识别反应模式。
元音识别模式在不同年龄组之间基本一致。老年听众受到某些元音对顺序的影响。并非所有元音对都能被同等准确地识别。还观察到了元音优势模式，在测试的元音对中，/a/被识别得最准确。共振峰动态部分解释了识别和混淆模式。
无论呈现模式、元音时长或大量刺激暴露的影响如何，元音识别的准确性模式在整个生命周期中都相当相似。观察到了元音顺序的大影响，特别是对老年听众而言。
