Boys Town National Research Hospital, Omaha, NE.
J Speech Lang Hear Res. 2020 Apr 27;63(4):1282-1298. doi: 10.1044/2020_JSLHR-19-00319. Epub 2020 Mar 26.
Purpose The goal of this study was to determine how various aspects of cognition predict speech recognition ability across different levels of speech vocoding within a single group of listeners. Method We tested the ability of young adults ( = 32) with normal hearing to recognize Perceptually Robust English Sentence Test Open-set (PRESTO) sentences that were degraded with a vocoder to produce different levels of spectral resolution (16, eight, and four carrier channels). Participants also completed tests of cognition (fluid intelligence, short-term memory, and attention), which were used as predictors of sentence recognition. Sentence recognition was compared across vocoder conditions, predictors were correlated with individual differences in sentence recognition, and the relationships between predictors were characterized. Results PRESTO sentence recognition performance declined with a decreasing number of vocoder channels, with no evident floor or ceiling performance in any condition. Individual ability to recognize PRESTO sentences was consistent relative to the group across vocoder conditions. Short-term memory, as measured with serial recall, was a moderate predictor of sentence recognition (ρ = 0.65). Serial recall performance was constant across vocoder conditions when measured with a digit span task. Fluid intelligence was marginally correlated with serial recall, but not sentence recognition. Attentional measures had no discernible relationship to sentence recognition and a marginal relationship with serial recall. Conclusions Verbal serial recall is a substantial predictor of vocoded sentence recognition, and this predictive relationship is independent of spectral resolution. In populations that show variable speech recognition outcomes, such as listeners with cochlear implants, it should be possible to account for the independent effects of spectral resolution and verbal serial recall in their speech recognition ability. Supplemental Material https://doi.org/10.23641/asha.12021051.
目的 本研究旨在确定在单个听力正常的受试群体中，认知的各个方面如何预测在不同语音编码水平下的言语识别能力。
方法 我们测试了 32 名年轻成年人识别感知稳健英语句子测试（PRESTO）句子的能力，这些句子通过语音编码器降质以产生不同水平的频谱分辨率（16、8 和 4 个载波通道）。参与者还完成了认知测试（流体智力、短期记忆和注意力），这些测试被用作句子识别的预测指标。我们比较了句子识别在语音编码条件下的表现，将预测指标与句子识别的个体差异相关联，并描述了预测指标之间的关系。
结果 PRESTO 句子识别性能随着语音编码器通道数量的减少而下降，在任何条件下都没有明显的下限或上限表现。个体识别 PRESTO 句子的能力在语音编码条件下相对稳定。以序列回忆测试衡量的短期记忆是句子识别的一个中等预测指标（ρ=0.65）。当使用数字跨度任务测量时，序列回忆在语音编码条件下的表现是恒定的。流体智力与序列回忆有边缘相关性，但与句子识别无关。注意措施与句子识别没有明显的关系，与序列回忆有边缘关系。
结论 言语序列回忆是语音编码句子识别的一个重要预测指标，这种预测关系独立于频谱分辨率。在言语识别结果存在差异的人群中，如人工耳蜗植入者，应该有可能在他们的言语识别能力中考虑频谱分辨率和言语序列回忆的独立影响。
