Division of Speech and Hearing Sciences, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, USA.
Department of Communication Sciences and Disorders, California State University Fullerton, Fullerton, California 92831, USA.
J Acoust Soc Am. 2024 Mar 1;155(3):2114-2127. doi: 10.1121/10.0025273.
Listeners show rapid perceptual learning of acoustically degraded speech, though the amount of exposure required to maximize speech adaptation is unspecified. The current work used a single-session design to examine the length of auditory training on perceptual learning for normal hearing listeners exposed to eight-channel noise-vocoded speech. Participants completed short, medium, or long training using a two-alternative forced choice sentence identification task with feedback. To assess learning and generalization, a 40-trial pre-test and post-test transcription task was administered using trained and novel sentences. Training results showed all groups performed near ceiling with no reliable differences. For test data, we evaluated changes in transcription accuracy using separate linear mixed models for trained or novel sentences. In both models, we observed a significant improvement in transcription at post-test relative to pre-test. Critically, the three training groups did not differ in the magnitude of improvement following training. Subsequent Bayes factors analysis evaluating the test by group interaction provided strong evidence in support of the null hypothesis. For these stimuli and procedure, results suggest increased training does not necessarily maximize learning outcomes; both passive and trained experience likely supported adaptation. Findings may contribute to rehabilitation recommendations for listeners adapting to degraded speech signals.
听众对语音受损的言语表现出快速的感知学习能力，尽管最大限度地适应语音所需的暴露量尚不清楚。本研究采用单次会话设计，考察了正常听力听众在暴露于八通道噪声编码言语后，进行听觉训练以获得感知学习的时长。参与者使用带反馈的二选一强制选择句子识别任务完成短、中或长的训练。为了评估学习和泛化，使用经过训练和新的句子进行了 40 次试验的预测试和转录测试。训练结果表明，所有组的表现都接近上限，没有可靠的差异。对于测试数据，我们使用分别针对训练句子和新句子的线性混合模型评估转录准确性的变化。在这两个模型中，我们观察到与预测试相比，后测试的转录准确性有显著提高。关键的是，在训练后，三个训练组在改善幅度上没有差异。随后对组间交互作用的测试进行贝叶斯因子分析，为支持零假设提供了强有力的证据。对于这些刺激和程序，结果表明增加训练不一定能最大限度地提高学习效果；被动和训练经验都可能支持适应。这些发现可能有助于为适应语音受损信号的听众提供康复建议。
