Department of Communication Sciences and Disorders, University of South Florida, 4202 E. Fowler Avenue, PCD1017, Tampa, Florida 33620, USA.
J Acoust Soc Am. 2010 Jul;128(1):410-23. doi: 10.1121/1.3436523.
The ability of native and non-native speakers to enhance intelligibility of target vowels by speaking clearly was compared across three talker groups: monolingual English speakers and native Spanish speakers with either an earlier or a later age of immersion in an English-speaking environment. Talkers produced the target syllables "bead, bid, bayed, bed, bad" and "bod" in 'conversational' and clear speech styles. The stimuli were presented to native English-speaking listeners in multi-talker babble with signal-to-noise ratios of -8 dB for the monolingual and early learners and -4 dB for the later learners. The monolinguals and early learners of English showed a similar average clear speech benefit, and the early learners showed equal or greater intelligibility than monolinguals for most target vowels. The 4-dB difference in signal-to-noise ratio yielded approximately equal average intelligibility for the monolinguals and later learners. The average clear speech benefit was smallest for the later learners, and a significant clear speech decrement was obtained for the target syllable "bid." These results suggest that later learners of English as a second language may be less able than monolinguals to accommodate listeners in noisy environments, due to a reduced ability to improve intelligibility by speaking more clearly.
本研究比较了以英语为母语者、英语早期浸入者和英语晚期浸入者三种说话者群体，考察了母语者和非母语者能否通过清晰发音来提高目标元音的可懂度。说话者以“日常交谈”和“清晰”两种发音方式发出“bead、bid、bayed、bed、bad”和“bod”这两个目标音节。这些刺激在多说话者背景噪声中呈现给以英语为母语的听众，对于单语者和英语早期浸入者，信噪比为-8dB，对于英语晚期浸入者，信噪比为-4dB。以英语为母语者和英语早期浸入者的清晰言语增益相似，对于大多数目标元音，英语早期浸入者的可懂度与单语者相当或更高。信噪比相差 4dB 导致单语者和英语晚期浸入者的平均可懂度大致相同。英语晚期浸入者的清晰言语增益最小，并且对于目标音节“bid”，可懂度明显下降。这些结果表明，作为第二语言的英语晚期学习者可能不如以英语为母语者能够适应嘈杂环境中的听众，因为他们通过更清晰地发音来提高可懂度的能力可能有所降低。
