Effects of Hearing Status on Adult Speech Production

这项应用的目标是：促进有关听力在言语产生中的作用的知识；描述听力障碍者的言语和假体的效果；以及评估和完善听力在言语中的作用模型的性质。我们通过对以下对象进行实验来追求这些目标：成年人工耳蜗使用者；助听器使用者；不使用假体的聋人扬声器；以及听力正常的扬声器。根据我们的听觉在成人言语运动控制中的作用模型，言语产生涉及听觉目标，从而涉及发音运动与其听觉结果之间的映射。该项目调查了：(1)长期耳聋后映射如何退化，当部分听力恢复时如何恢复，并受到听力短期变化的影响；(2)在有听力和无听力的情况下引入咬块对言语的影响；(3)有证据表明，说话者在接受人工耳蜗术后，音素变异到听觉目标的映射得到改善；(4)假体使用者的语音类别结构；(5)增加听觉目标的数量(通过比较具有不同元音库存的两种语言)对听觉反馈变化的反应的影响；(6)清晰度要求和听觉反馈对语音对比的影响；(7)言语参数随听力变化而变化的时间；(8)听力状况对所说音节视听整合的影响；(9)听力损失对可视言语激活听觉皮质的影响；(10)听力损失年龄对语音皮质激活的影响；(11)听力损失年龄对语音对比的影响。大多数研究中使用的自变量是：人工耳蜗的初始提供；听觉反馈的修改；以及修改的阶段(植入前、植入后不久、很长一段时间后)。一般来说，这些干预措施的效果是通过检查音素识别、皮质激活水平、在语音产生中选定的语音对比的声学测量-辅音和声学-以及整个声学元音空间的属性来评估的。

The goals of this application are: to contribute to the body of knowledge on the role of hearing in speech production; to describe the speech of hearing-impaired persons and the effects of prostheses; and to evaluate and refine the properties of a model of the role of hearing in speech. We pursue those goals by conducting experiments with: adult cochlear implant users; hearing aid users; deaf speakers who do not use prostheses; and speakers with normal hearing. According to our model of the role of hearing in adult speech motor control, speech production involves auditory goals and thus mappings between articulatory movements and their auditory consequences. The project investigates: (1) how mappings are degraded after long deafness, retuned when some hearing is restored, and affected by short-term changes in hearing; (2) the effects on speech when bite blocks are introduced with and without hearing; (3) evidence that the mapping of allophonic variation into auditory goals improves after the speaker receives a cochlear prosthesis; (4) the structure of phonetic categories in prosthesis users; (5) the effects of increasing the number of auditory goals (by comparing two languages with different vowel inventories) on responses to changes in auditory feedback; (6) the effects of clarity demands and auditory feedback on phonetic contrasts; (7) the timing of changes in speech parameters in response to changes in hearing; (8) effects of hearing status on audio-visual integration of spoken syllables; (9) effects of hearing loss on activation of auditory cortex by visible speech; (10) effects of age at hearing loss on cortical activation during speech; and (11) the effects of age at hearing loss on phonetic contrasts. Independent variables that are employed in most of the studies are: initial provision of a cochlear implant; modification of auditory feedback; and the stage at which the modification is made (before implantation, shortly after, long after). In general, the effects of these interventions are assessed by examining phoneme recognition, levels of cortical activation and, in speech production, acoustic measures of selected phonetic contrasts - consonantal and vocalic - as well as properties of the overall acoustic vowel space.