EFFECTS OF AAC STRATEGIES ON DYSARTHRIC SPEECH

描述(申请人提供)：可理解性是一个多方面的结构，它受到无数变量的影响，例如听者的语言语境知识，以及说话者产生的声学信号。然而，关于听者相关变量和说话者相关变量对发音清晰度的不同影响，或者这些变量在多大程度上可以被用来提高慢性构音障碍患者的发音清晰度，很少有系统的研究。本研究的长期目标是了解说话人相关变量和听者相关变量对不同严重程度慢性构音障碍患者语音可理解性的独立和交互作用。有构音障碍的说话者在同时说话时指向每个单词的第一个字母的干预策略，字母表补充(AS)，是本研究特别感兴趣的。初步研究表明，AS具有显著提高构音障碍语音清晰度的潜力；然而，清晰度提高的原因尚不清楚。假设与说话人相关的产出变化和提供给听话人的语言知识都起到了作用。两项相关研究将调查这些变量的影响。研究一将通过操纵语义可预测性和实验施加字母线索来考察内在和外在听者知识对习惯性构音障碍言语可理解性的影响。研究2将通过分析习惯性言语和在实施AS时产生的言语之间的频谱和时间声学差异，来检验与AS实施相关的说话人相关产出变化的影响。在这两项研究中，16名继发于脑瘫的构音障碍患者将作为演讲者，256名非残疾人将作为听众。听者将使用习惯性讲话和字母表补充，按正字法转录演讲者的录像带。清晰度数据和声学数据将进行方差分析，以回答研究问题。拟议的研究将收集与临床相关的疗效数据，将AS视为一种理论框架内的干预策略。这些研究的结果将提供关键的临床信息以及重要的理论信息，这些信息将开始量化构音障碍语音清晰度的贡献者。

DESCRIPTION (provided by applicant): Intelligibility is a multifaceted construct that is influenced by a myriad of variables such as linguistic-contextual knowledge of the listener, as well as the acoustic signal produced by the speaker. However, there has been little systematic investigation of the differential effects of listener-related and speaker-related variables on intelligibility or the extent to which these variables can be exploited to enhance intelligibility for speakers with chronic dysarthria. The long-term goal of this research is to understand the independent and interactive contributions of speaker-related and listener-related variables to speech intelligibility in individuals with chronic dysarthria of varying severity. The intervention strategy, alphabet supplementation (AS), in which speakers with dysarthria point to the first letter of each word while simultaneously speaking, is of particular interest in the present research. Preliminary studies suggest that AS has the potential to significantly enhance intelligibility of dysarthric speech; however; the reasons why intelligibility is improved are unknown. It is hypothesized that both speaker-related production changes and linguistic knowledge provided to listeners play a role. Two related studies will investigate the effects of these variables. Study 1 will examine the effects of intrinsic and extrinsic listener knowledge on intelligibility of habitual dysarthric speech through manipulation of semantic predictability and experimentally imposed alphabet cues. Study 2 will examine the effects of speaker-related production changes associated with implementation of AS through analysis of spectral and temporal acoustic differences between habitual speech and speech produced while implementing AS. Across both studies, 16 individuals with dysarthria secondary to cerebral palsy will serve as speakers and 256 non-disabled individuals will serve as listeners. Listeners will orthographically transcribe videotapes of speakers using habitual speech and using alphabet supplementation. Intelligibility data and acoustic data will be subjected to analysis of variance to answer research questions. The proposed studies will gather clinically-relevant efficacy data regarding AS as an intervention strategy within a theoretical framework. Outcomes of these studies will provide critical clinical information as well as important theoretical information that will begin to quantify contributors to speech intelligibility in dysarthria.