Dynamic specification of coarticulated vowels spoken in sentence context.
Dynamic specification of coarticulated vowels spoken in sentence context.
复制标题
句子上下文中所说的连读元音的动态规范。
DOI：
10.1121/1.397863
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发表时间：
1989
期刊：
影响因子：
--
通讯作者：
W. Strange
中科院分区：
文献类型：
--
作者：
W. Strange
根据一个动态的规范帐户，共发音元音识别的基础上随时间变化的声学信息，而不是仅仅基于“目标”的基础上包含在一个单一的频谱横截面的声学音节。本研究设计了三个实验，利用在载体句子中快速说出的辅音-元音-辅音（CVC）音节的数字分段部分来研究（1）发声核中可用的目标信息，（2）由音节长度指定的内在持续时间信息，以及（3）定义在音节起始和偏移上的动态频谱信息的相对贡献。在实验1和实验2中，研究了一名成年男性在三种辅音背景下发出的元音。结果表明，元音在沉默中心（SC）音节（其中的发声核被衰减到沉默离开初始和最后的过渡部分，在其原始的时间关系）被认为是相对准确的，虽然没有以及未修改的音节（实验1）;随机与阻塞的辅音上下文的介绍并不影响性能。错误率稍大的元音在SC音节中，内在的持续时间的差异被中和的初始和最终的过渡部分之间的无声间隔的持续时间相等。然而，性能显着优于当仅单独呈现初始转变或最终转变时（实验2）。实验3采用另一名成年男性产生的CVC刺激，并包括六个辅音上下文。SC音节和切除的音节核与适当的内在持续时间确定不低于未修改的控制准确。中和持续时间的差异，SC音节识别错误只略有增加，而截断切除音节核产生了更大的错误增加。这些结果表明，随时间变化的信息是必要的准确识别的共发音元音。两个假设的性质的动态信息指定的音节首和偏移进行了讨论。
According to a dynamic specification account, coarticulated vowels are identified on the basis of time-varying acoustic information, rather than solely on the basis of "target" information contained within a single spectral cross section of an acoustic syllable. Three experiments utilizing digitally segmented portions of consonant-vowel-consonant (CVC) syllables spoken rapidly in a carrier sentence were designed to examine the relative contribution of (1) target information available in vocalic nuclei, (2) intrinsic duration information specified by syllable length, and (3) dynamic spectral information defined over syllable onsets and offsets. In experiments 1 and 2, vowels produced in three consonantal contexts by an adult male were examined. Results showed that vowels in silent-center (SC) syllables (in which vocalic nuclei were attentuated to silence leaving initial and final transitional portions in their original temporal relationship) were perceived relatively accurately, although not as well as unmodified syllables (experiment 1); random versus blocked presentation of consonantal contexts did not affect performance. Error rates were slightly greater for vowels in SC syllables in which intrinsic duration differences were neutralized by equating the duration of silent intervals between initial and final transitional portions. However, performance was significantly better than when only initial transitions or final transitions were presented alone (experiment 2). Experiment 3 employed CVC stimuli produced by another adult male, and included six consonantal contexts. Both SC syllables and excised syllable nuclei with appropriate intrinsic durations were identified no less accurately than unmodified controls. Neutralizing duration differences in SC syllables increased identification errors only slightly, while truncating excised syllable nuclei yielded a greater increase in errors. These results demonstrate that time-varying information is necessary for accurate identification of coarticulated vowels. Two hypotheses about the nature of the dynamic information specified over syllable onsets and offsets are discussed.