Context:sensitivity/bias/parsing phonetic information

上下文：敏感性/偏差/解析语音信息

• 批准号: 6912759
• 负责人: JOHN C KINGSTON
• 金额: $ 27.48万
• 依托单位: UNIVERSITY OF MASSACHUSETTS AMHERST
• 依托单位国家: 美国
• 财政年份: 2004
• 资助国家: 美国
• 起止时间: 2004-07-01 至 2007-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6912759
• 关键词: auditory discrimination; auditory stimulus; behavioral /social science research tag; clinical research; human subject; neural information processing; nonEnglish language; psychoacoustics; sensory signal detection; speech recognition

DESCRIPTION: (provided by applicant): In fluent speech, speakers begin to pronounce the next sound before they're done pronouncing the last. As a result, speech sounds not only occur right next to one another but actually overlap, and pauses only occur between whole phrases and not individual sounds. This characteristic of fluent speech presents the listener with two formidable problems: separating overlapping sounds and then recognizing sounds whose acoustics have been distorted by the overlap with its neighbors' pronunciations. This proposal pursues the hypothesis that both separation and recognition can happen because successive intervals in the signal contrast with one another perceptually. For example, after an interval in which most of the sound energy is at high frequencies, a sound whose energy is at mid frequencies will sound relatively low, or after a relatively long interval, an interval of intermediate duration will sound relatively short. The experiments test a version of this hypothesis in which sequential contrast is exaggerated like this in the initial auditory evaluation of the sounds, before the listener has assigned any linguistic value to the sound, i.e. before the sounds are recognized as instances of particular categories. If sequential contrast arises before the sounds are recognized, then it will be impervious to any linguistic knowledge the listener may have, e.g. of whether the current sound makes a word with its context, occurs frequently in that context, is phonotactically legal in that context, etc. A separate, prelinguistic, auditory stage of phonetic processing is diagnosed by better discrimination of sound sequences that differ in the direction of their sequential contrast, e.g. high-low vs low-high, than of sequences that don't, i.e. high-high vs low-low. If linguistic knowledge is used at all stages of processing, these two pairs of sequences should instead be equally easy to distinguish because all the intervals will have been assigned to categories and will therefore be equally different. The results of these experiments therefore permit a choice between interactive models of speech sound recognition in which listeners use their linguistic knowledge at all stages in processing the speech sounds they hear and autonomous models in which they use only the psychoacoustic properties of the signal during the first stage, and only later apply what they know linguistically to the output of that stage. If the autonomous model is supported, then the robustness of speech perception under adverse conditions or by impaired listeners can be improved more by enhancing signal quality than adding redundant linguistic information.

描述：（由申请人提供）：在流利的语言中，说话者在发完最后一个音之前开始发下一个音。因此，语音不仅出现在彼此旁边，而且实际上是重叠的，停顿只出现在整个短语之间，而不是单个声音之间。流利说话的这一特点给听者带来了两个棘手的问题：一是分离重叠的音，二是识别那些因与邻近音重叠而失真的音。这一提议追求的假设是，分离和识别都可以发生，因为信号中的连续间隔在感知上彼此形成对比。例如，在大部分声音能量处于高频的间隔后，能量处于中频的声音听起来会相对较低，或者在较长的间隔后，中间持续时间的间隔听起来会相对较短。实验验证了这一假设的一个版本，即在听者赋予声音任何语言价值之前，即在声音被识别为特定类别的实例之前，在对声音的初始听觉评估中，顺序对比被这样夸大了。如果顺序对比在发音被识别之前就出现了，那么它将不受听者可能拥有的任何语言知识的影响，例如，当前的发音是否与上下文构成一个单词，在该上下文中频繁出现，在该上下文中语音是否合法等等。语音处理的一个独立的、前语言的听觉阶段是通过更好地辨别在顺序对比方向上不同的声音序列来诊断的，例如高-低vs低-高，而不是那些不相同的序列，例如高-高vs低-低。如果在处理的所有阶段都使用语言知识，这两对序列应该同样容易区分，因为所有的间隔将被分配给类别，因此将同样不同。因此，这些实验的结果允许在语音识别的交互式模型和自主模型之间进行选择，在这种模型中，听众在处理他们听到的语音的所有阶段使用他们的语言知识，而在自主模型中，他们在第一阶段只使用信号的心理声学特性，然后才将他们在语言上知道的应用到该阶段的输出。如果支持自治模型，那么通过增强信号质量而不是添加冗余语言信息，可以更好地提高不利条件下或受损听者语音感知的鲁棒性。