Department of Communication Disorders, University of Massachusetts Amherst, Amherst, Massachusetts, USA.
Department of Kinesiology, University of Massachusetts Amherst, Amherst, Massachusetts, USA.
Ear Hear. 2020 Sep/Oct;41(5):1383-1396. doi: 10.1097/AUD.0000000000000861.
The motivation for this research is to determine whether a listening-while-balancing task would be sensitive to quantifying listening effort in middle age. The premise behind this exploratory work is that a decrease in postural control would be demonstrated in challenging acoustic conditions, more so in middle-aged than in younger adults.
A dual-task paradigm was employed with speech understanding as one task and postural control as the other. For the speech perception task, participants listened to and repeated back sentences in the presence of other sentences or steady-state noise. Targets and maskers were presented in both spatially-coincident and spatially-separated conditions. The postural control task required participants to stand on a force platform either in normal stance (with feet approximately shoulder-width apart) or in tandem stance (with one foot behind the other). Participants also rated their subjective listening effort at the end of each block of trials.
Postural control was poorer for both groups of participants when the listening task was completed at a more adverse (vs. less adverse) signal-to-noise ratio. When participants were standing normally, postural control in dual-task conditions was negatively associated with degree of high-frequency hearing loss, with individuals who had higher pure-tone thresholds exhibiting poorer balance. Correlation analyses also indicated that reduced speech recognition ability was associated with poorer postural control in both single- and dual-task conditions. Middle-aged participants exhibited larger dual-task costs when the masker was speech, as compared to when it was noise. Individuals who reported expending greater effort on the listening task exhibited larger dual-task costs when in normal stance.
Listening under challenging acoustic conditions can have a negative impact on postural control, more so in middle-aged than in younger adults. One explanation for this finding is that the increased effort required to successfully listen in adverse environments leaves fewer resources for maintaining balance, particularly as people age. These results provide preliminary support for using this type of ecologically-valid dual-task paradigm to quantify the costs associated with understanding speech in adverse acoustic environments.
本研究旨在确定在中年时期，聆听平衡任务是否能够敏感地量化聆听努力。这项探索性工作的前提是，在具有挑战性的声学条件下，姿势控制会下降，中年人的情况比年轻人更为明显。
采用双任务范式，将言语理解作为一项任务，姿势控制作为另一项任务。在言语感知任务中，参与者在听和重复句子的同时，会有其他句子或稳态噪声的干扰。目标和掩蔽声在空间上一致和分离的条件下呈现。在姿势控制任务中，要求参与者在力平台上站立，姿势分别为正常站立（双脚约与肩同宽）或前后脚站立（一只脚在后）。参与者还在每个试验块结束时对他们的主观聆听努力进行评分。
当聆听任务在更不利（与较不利相比）的信噪比下完成时，两组参与者的姿势控制都更差。当参与者正常站立时，双任务条件下的姿势控制与高频听力损失程度呈负相关，纯音阈值较高的个体表现出较差的平衡能力。相关分析还表明，在单任务和双任务条件下，言语识别能力的降低与姿势控制的降低有关。与噪声相比，当掩蔽声是言语时，中年参与者在双任务中的代价更大。当处于正常站立时，报告在聆听任务上花费更多努力的个体在双任务中会产生更大的代价。
在具有挑战性的声学条件下聆听会对姿势控制产生负面影响，在中年时期比年轻人更为明显。对这一发现的一种解释是，在不利环境中成功聆听所需的努力增加，使得维持平衡的资源减少，尤其是随着人们年龄的增长。这些结果初步支持使用这种类型的生态有效双任务范式来量化在不利声学环境中理解言语所带来的成本。
