Jarollahi Farnoush, Valadbeigi Ayub, Jalaei Bahram, Maarefvand Mohammad, Motasaddi Zarandy Masoud, Haghani Hamid, Shirzhiyzn Zahra
Department of Audiology, School of Rehabilitation Sciences, Iran University of Medical Sciences, Tehran, Iran.
Cochlear Implant Center and Department of Otorhinolaryngology, Amir Aalam Hospital, Tehran University of Medical Sciences, Tehran, Iran.
Iran J Child Neurol. 2022 Spring;16(2):93-105. doi: 10.22037/ijcn.v16i2.27210. Epub 2022 Mar 14.
Many studies have suggested that cochlear implant (CI) users vary in terms of speech recognition in noise. Studies in this field attribute this variety partly to subcortical auditory processing. Studying speech-Auditory Brainstem Response (speech-ABR) provides good information about speech processing; thus, this work was designed to compare speech-ABR components between two groups of CI users with good and poor speech recognition in noise scores.
MATERIALS & METHODS: The present study was conducted on two groups of CI users aged 8-10 years old. The first group (CI-good) consisted of 15 children with prelingual CI who had good speech recognition in noise performance. The second group (CI-poor) was matched with the first group, but they had poor speech recognition in noise performance. The speech-ABR test in a sound-field presentation was performed for all the participants.
The speech-ABR response showed more delay in C, D, E, F, O latencies in CI-poor than CI-good users (P <0.05), meanwhile no significant difference was observed in initial wave (V(t= -0.293, p= 0.771 and A (t= -1.051, p= 0.307). Analysis in spectral-domain showed a weaker representation of fundamental frequency as well as the first formant and high-frequency component of speech stimuli in the CI users with poor auditory performance.
Results revealed that CI users who showed poor auditory performance in noise performance had deficits in encoding the periodic portion of speech signals at the brainstem level. Also, this study could be as physiological evidence for poorer pitch processing in CI users with poor speech recognition in noise performance.
许多研究表明，人工耳蜗（CI）使用者在噪声环境下的语音识别能力存在差异。该领域的研究将这种差异部分归因于皮层下听觉处理。研究言语听觉脑干反应（speech-ABR）可为语音处理提供良好信息；因此，本研究旨在比较两组在噪声环境下语音识别能力良好和较差的CI使用者之间的speech-ABR成分。
本研究针对两组8至10岁的CI使用者进行。第一组（CI-良好组）由15名语前聋人工耳蜗植入儿童组成，他们在噪声环境下具有良好的语音识别能力。第二组（CI-较差组）与第一组匹配，但他们在噪声环境下的语音识别能力较差。对所有参与者进行了声场呈现下的言语听觉脑干反应测试。
与CI-良好组使用者相比，CI-较差组使用者的言语听觉脑干反应在C、D、E、F、O潜伏期表现出更多延迟（P<0.05），同时在起始波（V（t = -0.293，p = 0.771）和A波（t = -1.051，p = 0.307）上未观察到显著差异。频谱域分析表明，听觉表现较差的CI使用者对语音刺激的基频以及第一共振峰和高频成分的表征较弱。
结果表明，在噪声环境下听觉表现较差的CI使用者在脑干水平对语音信号的周期性部分进行编码时存在缺陷。此外，本研究可为在噪声环境下语音识别能力较差的CI使用者音高处理较差提供生理学证据。
