Eaton-Peabody Laboratories, Massachusetts Eye and Ear Infirmary, Boston, United States.
Department of Otolaryngology - Head and Neck Surgery, Harvard Medical School, Boston, United States.
Elife. 2020 Jan 21;9:e51419. doi: 10.7554/eLife.51419.
In social settings, speech waveforms from nearby speakers mix together in our ear canals. Normally, the brain unmixes the attended speech stream from the chorus of background speakers using a combination of fast temporal processing and cognitive active listening mechanisms. Of >100,000 patient records,~10% of adults visited our clinic because of reduced hearing, only to learn that their hearing was clinically normal and should not cause communication difficulties. We found that multi-talker speech intelligibility thresholds varied widely in normal hearing adults, but could be predicted from neural phase-locking to frequency modulation (FM) cues measured with ear canal EEG recordings. Combining neural temporal fine structure processing, pupil-indexed listening effort, and behavioral FM thresholds accounted for 78% of the variability in multi-talker speech intelligibility. The disordered bottom-up and top-down markers of poor multi-talker speech perception identified here could inform the design of next-generation clinical tests for hidden hearing disorders.
在社交环境中，来自附近说话者的语音信号在我们的耳道中混合在一起。通常，大脑使用快速的时间处理和认知主动聆听机制的组合，从背景说话者的合唱中分离出关注的语音流。在超过 100,000 份患者记录中，约有 10%的成年人因听力下降而到我们的诊所就诊，但结果发现他们的听力在临床正常范围内，不应该导致交流困难。我们发现，正常听力成年人的多说话者语音可懂度阈值差异很大，但可以通过耳道 EEG 记录测量的神经相位锁定到频率调制 (FM) 线索来预测。结合神经时间精细结构处理、瞳孔索引的聆听努力和行为 FM 阈值，可以解释多说话者语音可懂度的 78%的可变性。这里确定的多说话者语音感知的不良自下而上和自上而下的标记物，可以为下一代隐藏性听力障碍的临床测试设计提供信息。
