Venezia Jonathan H, Leek Marjorie R, Lindeman Michael P
VA Loma Linda Healthcare System, CA.
Department of Otolaryngology-Head and Neck Surgery, School of Medicine, Loma Linda University, CA.
J Speech Lang Hear Res. 2020 Jul 20;63(7):2141-2161. doi: 10.1044/2020_JSLHR-19-00324. Epub 2020 Jun 30.
Purpose Age-related declines in auditory temporal processing and cognition make older listeners vulnerable to interference from competing speech. This vulnerability may be increased in older listeners with sensorineural hearing loss due to additional effects of spectral distortion and accelerated cognitive decline. The goal of this study was to uncover differences between older hearing-impaired (OHI) listeners and older normal-hearing (ONH) listeners in the perceptual encoding of competing speech signals. Method Age-matched groups of 10 OHI and 10 ONH listeners performed the coordinate response measure task with a synthetic female target talker and a male competing talker at a target-to-masker ratio of +3 dB. Individualized gain was provided to OHI listeners. Each listener completed 50 baseline and 800 "bubbles" trials in which randomly selected segments of the speech modulation power spectrum (MPS) were retained on each trial while the remainder was filtered out. Average performance was fixed at 50% correct by adapting the number of segments retained. Multinomial regression was used to estimate weights showing the regions of the MPS associated with performance (a "classification image" or CImg). Results The CImg weights were significantly different between the groups in two MPS regions: a region encoding the shared phonetic content of the two talkers and a region encoding the competing (male) talker's voice. The OHI listeners demonstrated poorer encoding of the phonetic content and increased vulnerability to interference from the competing talker. Individual differences in CImg weights explained over 75% of the variance in baseline performance in the OHI listeners, whereas differences in high-frequency pure-tone thresholds explained only 10%. Conclusion Suprathreshold deficits in the encoding of low- to mid-frequency (~5-10 Hz) temporal modulations-which may reflect poorer "dip listening"-and auditory grouping at a perceptual and/or cognitive level are responsible for the relatively poor performance of OHI versus ONH listeners on a different-gender competing speech task. Supplemental Material https://doi.org/10.23641/asha.12568472.
目的 与年龄相关的听觉时间处理和认知能力下降使老年听众容易受到竞争性言语干扰的影响。由于频谱失真和认知衰退加速的额外影响，这种易感性在患有感音神经性听力损失的老年听众中可能会增加。本研究的目的是揭示老年听力受损（OHI）听众和老年听力正常（ONH）听众在竞争性言语信号的感知编码方面的差异。方法 年龄匹配的10名OHI听众和10名ONH听众组成的小组，以+3 dB的目标-掩蔽比，对合成的女性目标说话者和男性竞争性说话者执行坐标反应测量任务。为OHI听众提供个性化增益。每个听众完成50次基线试验和800次“气泡”试验，在每次试验中，语音调制功率谱（MPS）的随机选择段被保留，其余部分被滤除。通过调整保留的段数，平均表现固定在50%正确。多项回归用于估计权重，显示与表现相关的MPS区域（“分类图像”或CImg）。结果 在两个MPS区域中，两组之间的CImg权重存在显著差异：一个区域编码两个说话者的共享语音内容，另一个区域编码竞争性（男性）说话者的声音。OHI听众在语音内容编码方面表现较差，且更容易受到竞争性说话者干扰的影响。CImg权重的个体差异解释了OHI听众基线表现中超过75%的方差，而高频纯音阈值的差异仅解释了10%。结论 低频至中频（约5-10 Hz）时间调制编码中的阈上缺陷——这可能反映了较差的“低谷聆听”——以及感知和/或认知水平上的听觉分组，是OHI听众在不同性别竞争性言语任务中表现相对较差的原因。补充材料 https://doi.org/10.23641/asha.12568472 。
