ACOUSTIC AND PERCEPTUAL INVARIANCE IN SPEECH

这项研究的主要目的是阐明语音的属性如何映射到词汇上。目前的建议侧重于表征语音类别的结构，包括边界限制和内部结构，以及这些类别到词汇形式的映射。将探索语音类别的边界约束，以确定被称为标准属性的特定声学属性是否在许多可变性来源中保持稳定，包括语言的影响、音素对比的存在或不存在、音段(辅音或元音)的内在性质的影响、次级发音对声学属性出现的影响、以及回归同化和元音环境的影响。语音类别内部结构的“形状”将通过探索语言具有表示语音类别的“偏好”或原型区域的程度；标准属性和与其相关联的定义该类别的最佳样本的“家族”值之间的关系；以及标准属性的“最佳样本”的范围可能在多大程度上受语速和其他声学参数的存在的影响来绘制。语音类别到词汇形式的映射将通过评估影响语音类别结构的声学变化最终是否以及以何种方式影响词汇形式来进行。实验将考察确定或不定义语音类别的声学变量的作用，语音位置和音节重音的影响，以及先前词汇激活(自上而下的加工)对亚语音效应在词汇通达中出现的影响。研究方法包括语音的声学分析和定量算法的开发，以及为了进行语音感知和词汇决策实验而对自然语音进行计算机编辑。这项研究应该会对语音处理系统以及它如何与更高级别的语言处理进行交互提供更多的了解。表征正常成年人的言语过程是理解言语和语言病理的基础，尤其是在成年人，也包括在儿童中。

The broad goal of this research is to explicate how the properties of sound map on the lexicon. The current proposal focuses on a characterization of the structure of phonetic categories, including both boundary constraints and internal structure, and the mapping of these categories on to lexical form. Boundary constraints of phonetic categories will be explored to determine whether particular acoustic properties called criterial attributes remain stable across a number of sources of variability including the influence of language, the presence or absence of phonemic contrast, the influence of the intrinsic nature of the sound segment (consonant or vowel), the influence of a secondary articulation on the emergence of an acoustic property, and the influence of regressive assimilation and vowel environment. The 'shape' of the internal structure of phonetic categories will be charted by exploring the extent to which languages have 'preferred' or prototypical region for the representation of a phonetic category; the relationship between a criterial attribute and the 'family' of values associated with it to define the best exemplar for that category; and the extent to which to which a range of 'best exemplars' of a criterial attribute may be influenced by speaking rate and the presence of other acoustic parameters. The mapping of phonetic categories on to lexical form will be investigated by assess whether and in which ways the acoustic variations which to and affect phonetic category structure ultimately impact lexical form. Experiments will investigate the role of acoustic variants that do or do not define phonetic categories, the influence of phonetic position and syllable stress, and the influence of prior lexical activation (top-down processing) on the emergence of subphonetic effects on lexical access. Research methods include acoustic analyses of speech and development of quantitative algorithms, computer-editing of natural speech in order to conduct both speech perception and lexical decision experiments. This research should provide a greater understanding of the speech processing system and how it interfaces with higher levels of language processing. Characterizing the speech processing of normal adults serves as the basis for the understanding of pathologies of speech and language, particularly in adults, but also in children.