Wendt Dorothea, Dau Torsten, Hjortkjær Jens
Hearing Systems, Hearing Systems Group, Department of Electrical Engineering, Technical University of DenmarkKongens Lyngby, Denmark; Eriksholm Research CentreSnekkersten, Denmark.
Hearing Systems, Hearing Systems Group, Department of Electrical Engineering, Technical University of Denmark Kongens Lyngby, Denmark.
Front Psychol. 2016 Mar 10;7:345. doi: 10.3389/fpsyg.2016.00345. eCollection 2016.
Speech comprehension in adverse listening conditions can be effortful even when speech is fully intelligible. Acoustical distortions typically make speech comprehension more effortful, but effort also depends on linguistic aspects of the speech signal, such as its syntactic complexity. In the present study, pupil dilations, and subjective effort ratings were recorded in 20 normal-hearing participants while performing a sentence comprehension task. The sentences were either syntactically simple (subject-first sentence structure) or complex (object-first sentence structure) and were presented in two levels of background noise both corresponding to high intelligibility. A digit span and a reading span test were used to assess individual differences in the participants' working memory capacity (WMC). The results showed that the subjectively rated effort was mostly affected by the noise level and less by syntactic complexity. Conversely, pupil dilations increased with syntactic complexity but only showed a small effect of the noise level. Participants with higher WMC showed increased pupil responses in the higher-level noise condition but rated sentence comprehension as being less effortful compared to participants with lower WMC. Overall, the results demonstrate that pupil dilations and subjectively rated effort represent different aspects of effort. Furthermore, the results indicate that effort can vary in situations with high speech intelligibility.
即使语音完全可懂，在不利的听力条件下进行言语理解也可能需要付出努力。声学失真通常会使言语理解更加费力，但努力程度也取决于言语信号的语言方面，比如其句法复杂性。在本研究中，对20名听力正常的参与者在执行句子理解任务时的瞳孔扩张和主观努力程度评分进行了记录。句子要么是句法简单的（主语在前的句子结构），要么是复杂的（宾语在前的句子结构），并在两种对应高可懂度的背景噪声水平下呈现。使用数字广度和阅读广度测试来评估参与者工作记忆容量（WMC）的个体差异。结果表明，主观评定的努力程度主要受噪声水平影响，受句法复杂性的影响较小。相反，瞳孔扩张随句法复杂性增加，但仅显示出较小的噪声水平效应。与低WMC的参与者相比，高WMC的参与者在较高水平噪声条件下瞳孔反应增强，但评定句子理解的努力程度较低。总体而言，结果表明瞳孔扩张和主观评定的努力程度代表了努力的不同方面。此外，结果表明在言语可懂度高的情况下，努力程度也可能有所不同。
