Department of Otorhinolaryngology, The First Hospital of Dalian Medical University, Dalian, China.
Department of Communicative Disorders and Sciences, Center for Hearing and Deafness, State University of New York at Buffalo, Buffalo, NY, USA.
Neural Plast. 2022 Nov 21;2022:6463355. doi: 10.1155/2022/6463355. eCollection 2022.
Sound stimulation is generally used for tinnitus and hyperacusis treatment. Recent studies found that long-term noise exposure can change synaptic and firing properties in the central auditory system, which will be detected by the acoustic startle reflex. However, the perceptual consequences of long-term low-intensity sound exposure are indistinct. This study will detect the effects of moderate-level noise exposure (83 dB SPL) on auditory loudness, and temporal processing was evaluated using CBA/CaJ mice. C-Fos staining was used to detect neural activity changes in the central auditory pathway. With two weeks of 83 dB SPL noise exposure (8 hours per day), no persistent threshold shift of the auditory brainstem response (ABR) was identified. On the other hand, noise exposure enhanced the acoustic startle response (ASR) and gap-induced prepulse inhibition significantly (gap-PPI). Low-level noise exposure, according to the findings, can alter temporal acuity. Noise exposure increased the number of c-Fos labeled neurons in the dorsal cochlear nucleus (DCN) and caudal pontine reticular nucleus (PnC) but not at a higher level in the central auditory nuclei. Our results suggested that noise stimulation can change acoustical temporal processing presumably by increasing the excitability of auditory brainstem neurons.
声音刺激通常用于治疗耳鸣和听觉过敏。最近的研究发现，长期的噪声暴露会改变中枢听觉系统中的突触和放电特性，这将通过听觉惊跳反射检测到。然而，长期低强度声音暴露的感知后果尚不清楚。本研究将检测中强度噪声暴露（83dB SPL）对听觉响度的影响，并使用 CBA/CaJ 小鼠评估时间处理。使用 c-Fos 染色来检测中枢听觉通路中的神经活动变化。经过两周 83dB SPL 噪声暴露（每天 8 小时），未发现听觉脑干反应（ABR）的持续阈值偏移。另一方面，噪声暴露显著增强了听觉惊跳反应（ASR）和间隙诱发的前脉冲抑制（gap-PPI）。根据研究结果，低水平噪声暴露会改变时间辨别力。噪声暴露增加了耳蜗背核（DCN）和桥脑尾侧网状核（PnC）中 c-Fos 标记神经元的数量，但在更高水平的中枢听觉核中没有增加。我们的结果表明，噪声刺激可以通过增加听觉脑干神经元的兴奋性来改变声音的时间处理。
