Department of Radiology, Nanjing First Hospital, Nanjing Medical University, Nanjing, China.
School of Human Communication Disorders, Dalhousie University, Halifax, Nova Scotia, Canada.
CNS Neurosci Ther. 2023 Mar;29(3):932-940. doi: 10.1111/cns.14028. Epub 2022 Nov 15.
This study aimed to explore the neural substrate of hearing loss-related central nervous system in rats and its correlation with cognition.
We identified the neural mechanism for these debilitating abnormalities by inducing a bilateral hearing loss animal model using intense broadband noise (122 dB of broadband noise for 2 h) and used the Morris water maze test to characterize the behavioral changes at 6 months post-noise exposure. Functional magnetic resonance imaging (fMRI) was conducted to clarify disrupted functional network using bilateral auditory cortex (ACx) as a seed. Structural diffusion tensor imaging (DTI) was applied to illustrate characteristics of fibers in ACx and hippocampus. Pearson correlation was computed behavioral tests and other features.
A deficit in spatial learning/memory, body weight, and negative correlation between them was observed. Functional connectivity revealed weakened coupling within the ACx and inferior colliculus, lateral lemniscus, the primary motor cortex, the olfactory tubercle, hippocampus, and the paraflocculus lobe of the cerebellum. The fiber number and mean length of ACx and different hippocampal subregions were also damaged in hearing loss rats.
A new model of auditory-limbic-cerebellum interactions accounting for noise-induced hearing loss and cognitive impairments is proposed.
本研究旨在探讨大鼠听力损失相关中枢神经系统的神经基础及其与认知的相关性。
我们通过使用强宽带噪声（122dB 的宽带噪声持续 2 小时）诱导双侧听力损失动物模型，确定了这些使人衰弱的异常的神经机制，并在噪声暴露后 6 个月使用 Morris 水迷宫测试来描述行为变化。使用双侧听觉皮层（ACx）作为种子进行功能磁共振成像（fMRI），以阐明功能网络的中断。应用结构扩散张量成像（DTI）来描述 ACx 和海马体中的纤维特征。计算了行为测试和其他特征之间的 Pearson 相关性。
观察到空间学习/记忆缺陷、体重减轻以及它们之间的负相关。功能连接显示，ACx 与下丘、外侧丘系、初级运动皮层、嗅结节、海马体和小脑的副小叶之间的耦合减弱。听力损失大鼠的 ACx 和不同海马亚区的纤维数量和平均长度也受到了损伤。
提出了一个新的听觉-边缘-小脑相互作用模型，解释了噪声引起的听力损失和认知障碍。
