Department of Speech and Hearing Science, University of Illinois Urbana-Champaign.
Lang Speech Hear Serv Sch. 2023 Oct 2;54(4):1195-1207. doi: 10.1044/2023_LSHSS-22-00158. Epub 2023 Jun 21.
The purpose of this project is to assess the acoustical conditions in which optimal intelligibility and low listening difficulty can be achieved in real classrooms for elementary students, taking into consideration the effects of dysphonic voice and typical classroom noise.
Speech intelligibility tests were performed in six elementary classrooms with 80 normal-hearing students aged 7-11 years. The speech material was produced by a female actor using a normal voice quality and simulating a dysphonic voice. The stimuli were played by a Head and Torso Simulator. Child babble noise and classrooms with different reverberation times were used to obtain a Speech Transmission Index (STI) range from 0.2 to 0.7, corresponding to the categories bad, poor, fair, and good.
The results showed a statistically significant decrease in intelligibility when the speaker was dysphonic, in STI higher than 0.33. The rating of listening difficulty showed a significantly greater difficulty in perceiving the dysphonic voice. In addition, younger children showed poorer performance and greater listening difficulty compared with older children when listening to the normal voice quality. Both groups were equally impacted when the voice was dysphonic.
The results suggested that better acoustic conditions are needed for children to reach a good level of intelligibility and to reduce listening difficulty if the teacher is suffering from voice problems. This was true for children regardless of grade level, highlighting the importance of ensuring more favorable acoustic conditions for children throughout all elementary schools.
本项目旨在评估小学生实际教室中能够实现最佳可懂度和低聆听难度的声学条件，同时考虑到声音嘶哑和典型教室噪声的影响。
在六间有 80 名正常听力的 7-11 岁学生的小学教室里进行了语音可懂度测试。语音材料由一位女性演员使用正常音质并模拟声音嘶哑来产生。刺激由头和躯干模拟器播放。使用儿童的背景噪声和具有不同混响时间的教室，获得语音传输指数（STI）范围为 0.2 至 0.7，对应于差、差、尚可和良好的类别。
结果表明，当说话人声音嘶哑时，可懂度会显著下降，STI 高于 0.33。听力困难的评分表明，感知声音嘶哑时的难度明显更大。此外，与年龄较大的儿童相比，较小的儿童在听到正常音质时表现出较差的性能和更大的听力困难。当声音嘶哑时，两组儿童的表现都受到了同样的影响。
结果表明，如果教师有嗓音问题，儿童需要更好的声学条件才能达到良好的可懂度水平，并降低聆听难度。这对不同年级的儿童都是如此，这突显了确保整个小学阶段为儿童提供更有利的声学条件的重要性。
