Hearing Research Program, Department of Otolaryngology-Head and Neck Surgery, Medical University of South Carolina, 135 Rutledge Avenue, MSC 55, Charleston, SC, 29425-5500, USA.
Department of Psychology, Auburn University, Auburn, AL, 36849, USA.
Brain Struct Funct. 2022 Jan;227(1):203-218. doi: 10.1007/s00429-021-02398-2. Epub 2021 Oct 10.
Older adults with hearing loss experience significant difficulties understanding speech in noise, perhaps due in part to limited benefit from supporting executive functions that enable the use of environmental cues signaling changes in listening conditions. Here we examined the degree to which 41 older adults (60.56-86.25 years) exhibited cortical responses to informative listening difficulty cues that communicated the listening difficulty for each trial compared to neutral cues that were uninformative of listening difficulty. Word recognition was significantly higher for informative compared to uninformative cues in a + 10 dB signal-to-noise ratio (SNR) condition, and response latencies were significantly shorter for informative cues in the + 10 dB SNR and the more-challenging + 2 dB SNR conditions. Informative cues were associated with elevated blood oxygenation level-dependent contrast in visual and parietal cortex. A cue-SNR interaction effect was observed in the cingulo-opercular (CO) network, such that activity only differed between SNR conditions when an informative cue was presented. That is, participants used the informative cues to prepare for changes in listening difficulty from one trial to the next. This cue-SNR interaction effect was driven by older adults with more low-frequency hearing loss and was not observed for those with more high-frequency hearing loss, poorer set-shifting task performance, and lower frontal operculum gray matter volume. These results suggest that proactive strategies for engaging CO adaptive control may be important for older adults with high-frequency hearing loss to optimize speech recognition in changing and challenging listening conditions.
老年听力损失患者在噪声环境中理解言语存在显著困难,这可能部分归因于执行功能支持有限,而执行功能有助于利用环境线索来指示听力条件的变化。在这里,我们研究了 41 名老年人(60.56-86.25 岁)对有信息量的听力困难线索的皮质反应程度,这些线索传达了每个试验的听力困难程度,而中性线索则对听力困难没有提示作用。与中性线索相比,在+10dB 信噪比(SNR)条件下,有信息量的线索可显著提高单词识别率,而在+10dB SNR 和更具挑战性的+2dB SNR 条件下,有信息量的线索的反应潜伏期显著缩短。有信息量的线索与视觉和顶叶皮层的血氧水平依赖对比升高有关。在扣带-顶叶(CO)网络中观察到了线索-SNR 相互作用效应,即只有在呈现有信息量的线索时,活动才会在 SNR 条件之间存在差异。也就是说,参与者使用有信息量的线索来为下一次试验中听力难度的变化做好准备。这种线索-SNR 相互作用效应是由低频听力损失更严重的老年人驱动的,而高频听力损失更严重、转换任务表现更差以及额骨外侧回灰质体积较低的老年人则没有观察到这种效应。这些结果表明,对于高频听力损失的老年人来说,主动参与 CO 适应性控制的策略可能对优化变化和挑战性听力条件下的言语识别非常重要。