Audiology and Speech Pathology Center, Walter Reed National Military Medical Center, Bethesda, MD.
Applied Research Laboratory for Intelligence and Security, University of Maryland, College Park.
J Speech Lang Hear Res. 2023 Oct 4;66(10):4066-4082. doi: 10.1044/2023_JSLHR-22-00548. Epub 2023 Sep 6.
This study examined the extent to which acoustic, linguistic, and cognitive task demands interactively impact listening effort.
Using a dual-task paradigm, on each trial, participants were instructed to perform either a single task or two tasks. In the primary word recognition task, participants repeated Northwestern University Auditory Test No. 6 words presented in speech-shaped noise at either an easier or a harder signal-to-noise ratio (SNR). The words varied in how commonly they occur in the English language (lexical frequency). In the secondary visual task, participants were instructed to press a specific key as soon as a number appeared on screen (simpler task) or one of two keys to indicate whether the visualized number was even or odd (more complex task).
Manipulation checks revealed that key assumptions of the dual-task design were met. A significant three-way interaction was observed, such that the expected effect of SNR on effort was only observable for words with lower lexical frequency and only when multitasking demands were relatively simpler.
This work reveals that variability across speech stimuli can influence the sensitivity of the dual-task paradigm for detecting changes in listening effort. In line with previous work, the results of this study also suggest that higher cognitive demands may limit the ability to detect expected effects of SNR on measures of effort. With implications for real-world listening, these findings highlight that even relatively minor changes in lexical and multitasking demands can alter the effort devoted to listening in noise.
本研究考察了声学、语言学和认知任务需求的相互作用对听力努力程度的影响程度。
使用双任务范式，在每个试验中，指示参与者执行单一任务或两项任务。在主要的单词识别任务中，参与者重复以语音形状噪声呈现的西北大学听觉测试 6 单词，信号噪声比（SNR）要么更容易，要么更难。这些单词在英语中的出现频率（词汇频率）不同。在次要的视觉任务中，参与者被指示一旦屏幕上出现数字，就按下特定的键（更简单的任务），或者按下两个键之一，以指示可视化的数字是偶数还是奇数（更复杂的任务）。
操作检查显示，双任务设计的关键假设得到满足。观察到显著的三向交互作用，即 SNR 对努力的预期影响仅在词汇频率较低的单词中观察到，并且只有在多重任务需求相对较简单时才观察到。
这项工作表明，语音刺激的变化会影响双任务范式检测听力努力变化的敏感性。与之前的工作一致，本研究的结果还表明，更高的认知需求可能会限制检测 SNR 对努力度测量的预期影响的能力。这些发现对现实世界的听力具有影响，它们表明，词汇和多重任务需求的相对较小变化都可以改变在噪声中投入的听力努力程度。
