Effects of Hearing Status on Adult Speech Production

描述（由申请人提供）：这项申请持续资助的目标是：显著加深我们对说话者的听觉敏锐度如何影响他或她的言语运动计划的理解；描述成人听障者的语言感知和产生及人工耳蜗的影响；评估并帮助完善听力在言语中的作用的定量模型。为了实现这些目标，我们对听力正常的说话者和接受人工耳蜗植入的语后失聪成年人进行了实验。我们的实验测量了植入物在植入前和植入后长达2年的录音中对说话者听觉敏锐度的影响。根据我们的听力在成人言语运动控制中的作用模型，言语运动的许多目标都在听觉领域。因此，本研究的一个中心主题是听觉感知在语音过程中用于实现听觉目标的反馈和前馈控制系统中的作用。在成人中，前馈控制几乎完全负责产生关节运动。然而，当说话者的意图和语音产生过程中产生的听觉反馈不匹配时，这种错误会导致纠正运动命令，用于更新后续动作的前馈命令。说话者发现这种不匹配的能力取决于他或她的听觉敏锐度。本研究探讨了听觉敏锐度在产生音素和词汇重音对比中的作用；当补偿元音共振峰的反馈扰动或对振动谱的机械扰动时；当模仿合成元音时。为了测量敏锐度，我们提出了用于识别测试的合成语音延续。为了评估与敏锐度的关系，我们测量了对比音素和词汇重音的分离程度；产品围绕其音素手段的分散；共振谱的形成峰位移和力学扰动补偿；和模仿的准确性。在大多数这些实验中，我们也暂时阻断听觉反馈，以揭示前馈命令的状态。分析考虑了人口统计学变量，如听力损失的年龄和植入物使用的持续时间。与公众健康的相关性：听自己说话对保持良好的语言有双重作用——它可以纠正语音的发音，甚至在语音出现的时候，它可以修改下一次发出声音的计划。当说话者有严重的听力障碍时，这两种机制就不能很好地发挥作用，语言能力会随着时间的推移而恶化。这个项目研究的观点是，受影响最大的人是那些不能很好地区分不同语音的人。这一结果可以促进新疗法的研究，通过训练患者更好地听出他们发出的声音之间的差异，减轻某些语言障碍，包括语言发育障碍。

DESCRIPTION (provided by applicant): The goals of this application for continuation funding are: to deepen significantly our understanding of how a speaker's auditory acuity influences his or her speech motor planning; to describe the speech perception and production of hearing-impaired adults and the effects of cochlear prostheses; and to evaluate and help refine a quantitative model of the role of hearing in speech. We pursue these goals by conducting experiments with normal-hearing speakers, and with postlingually deafened adults who receive cochlear implants. Our experiments measure the effects of the implants on speech in recordings made before implantation and up to 2 years after, as speakers' auditory acuity evolves. According to our model of the role of hearing in adult speech motor control, many of the goals of speech movements are in the auditory domain. Consequently, a central theme of this research is the role of auditory perception in the feedback and feedforward control systems that are used to achieve auditory goals during speech. Feedforward control is almost entirely responsible for generating articulatory movements in adults. However, when there is a mismatch between the speaker's intention and the resulting auditory feedback during production of a speech sound, that error leads to corrective motor commands that serve to update feedforward commands for subsequent movements. The speaker's ability to detect such a mismatch depends on his or her auditory acuity. The proposed research inquires into the role of auditory acuity when producing phoneme and lexical stress contrasts; when compensating for feedback perturbation of vowel formants or for mechanical perturbation of sibilant spectra; and when imitating synthesized vowels. To measure acuity, we present synthetic speech continuation for discrimination testing. To assess relations with acuity, we measure the degree of separation of contrastive phonemes and lexical stress; dispersion of productions around their phoneme means; compensation for formant shift and for mechanical perturbation of sibilant spectra; and imitation accuracy. In most of these experiments, we also block auditory feedback temporarily in order to reveal the state of feedforward commands. Analyses take demographic variables such as age at hearing loss and duration of implant use into account. Relevance to public health: Hearing oneself speak plays a 2-fold role in maintaining good speech-it may correct the pronunciation of speech sounds even as they are occurring and it can revise plans for producing the sound next time. When a speaker is seriously hearing-impaired, those 2 mechanisms do not function well and speech can deteriorate over time. This project studies the idea that the people most affected are those who cannot distinguish the different speech sounds well. The results can serve to stimulate research on new therapies in which certain speech disorders, including those of speech development, are alleviated by training clients to hear differences better among the sounds that they produce.