Chiu Yi-Fang, Forrest Karen
Department of Communication Sciences and Disorders, Saint Louis University, MO.
Department of Speech and Hearing Sciences, Indiana University Bloomington.
J Speech Lang Hear Res. 2018 Apr 17;61(4):837-846. doi: 10.1044/2017_JSLHR-S-17-0205.
This study investigated the impact of lexical characteristics on the intelligibility of speakers with Parkinson's disease (PD). Intelligibility was compared for listening in a quiet versus a noisy environment.
A total of 192 young listeners participated in the study, with 96 listeners listening in quiet and 96 listening in noise in which the spoken sentences were mixed with 10-talker babble. The listeners transcribed spoken sentences with target words controlled for word frequency and neighborhood density. The sentences were produced by 12 speakers with PD and 12 healthy control (HC) speakers. Transcription accuracy was compared across lexical categories between PD and HC and between the two listening conditions.
Transcription accuracy was higher for high-frequency words than low-frequency words for both speaker groups in quiet and in noise. The neighborhood density effect was evident only in the noise condition with better intelligibility for words from sparse neighborhoods than from dense neighborhoods. Regardless of listening condition, the PD group was less intelligible with a significant decrease in intelligibility in noise relative to quiet.
The lexical properties of the words affected listeners' understanding of Parkinsonian speech. Frequent words in sparse neighborhood enhanced intelligibility, especially under adverse listening conditions. Babble noise had a detrimental impact on the intelligibility of Parkinsonian speech. The extent of the lexical effect on intelligibility increased in noise.
本研究调查了词汇特征对帕金森病（PD）患者言语可懂度的影响。比较了在安静环境和嘈杂环境中聆听时的可懂度。
共有192名年轻听众参与了这项研究，其中96名听众在安静环境中聆听，96名听众在嘈杂环境中聆听，嘈杂环境中的口语句子与10人嘈杂语混合。听众转录口语句子，目标词的词频和邻域密度受到控制。这些句子由12名帕金森病患者和12名健康对照（HC）者说出。比较了帕金森病患者和健康对照者之间以及两种聆听条件下不同词汇类别的转录准确性。
在安静和嘈杂环境中，两个说话者组的高频词转录准确性均高于低频词。邻域密度效应仅在嘈杂环境中明显，稀疏邻域的词比密集邻域的词可懂度更高。无论聆听条件如何，帕金森病患者组的可懂度较低，与安静环境相比，嘈杂环境中的可懂度显著下降。
词汇的特性影响听众对帕金森病患者言语的理解。稀疏邻域中的高频词提高了可懂度，尤其是在不利的聆听条件下。嘈杂语对帕金森病患者言语的可懂度有不利影响。在嘈杂环境中，词汇对可懂度的影响程度增加。
