Guan Bing, Xu Yixi, Chen Yu-Chen, Xing Chunhua, Xu Li, Shang Song'an, Xu Jin-Jing, Wu Yuanqing, Yan Qi
Department of Otolaryngology, Head and Neck Surgery, Clinical Medical College, Yangzhou University, Yangzhou, China.
Department of Radiology, Nanjing First Hospital, Nanjing Medical University, Nanjing, China.
Front Aging Neurosci. 2022 May 26;14:905487. doi: 10.3389/fnagi.2022.905487. eCollection 2022.
Presbycusis is characterized by bilateral sensorineural hearing loss at high frequencies and is often accompanied by cognitive decline. This study aimed to identify the topological reorganization of brain functional network in presbycusis with/without cognitive decline by using graph theory analysis approaches based on resting-state functional magnetic resonance imaging (rs-fMRI).
Resting-state fMRI scans were obtained from 30 presbycusis patients with cognitive decline, 30 presbycusis patients without cognitive decline, and 50 age-, sex-, and education-matched healthy controls. Graph theory was applied to analyze the topological properties of brain functional networks including global and nodal metrics, modularity, and rich-club organization.
At the global level, the brain functional networks of all participants were found to possess small-world properties. Also, significant group differences in global network metrics were observed among the three groups such as clustering coefficient, characteristic path length, normalized characteristic path length, and small-worldness. At the nodal level, several nodes with abnormal betweenness centrality, degree centrality, nodal efficiency, and nodal local efficiency were detected in presbycusis patients with/without cognitive decline. Changes in intra-modular connections in frontal lobe module and inter-modular connections in prefrontal subcortical lobe module were found in presbycusis patients exposed to modularity analysis. Rich-club nodes were reorganized in presbycusis patients, while the connections among them had no significant group differences.
Presbycusis patients exhibited topological reorganization of the whole-brain functional network, and presbycusis patients with cognitive decline showed more obvious changes in these topological properties than those without cognitive decline. Abnormal changes of these properties in presbycusis patients may compensate for cognitive impairment by mobilizing additional neural resources.
老年性聋的特征是高频双侧感音神经性听力损失，且常伴有认知功能下降。本研究旨在通过基于静息态功能磁共振成像（rs-fMRI）的图论分析方法，识别伴有/不伴有认知功能下降的老年性聋患者脑功能网络的拓扑重组。
对30例伴有认知功能下降的老年性聋患者、30例不伴有认知功能下降的老年性聋患者以及50例年龄、性别和教育程度匹配的健康对照者进行静息态fMRI扫描。应用图论分析脑功能网络的拓扑特性，包括全局和节点指标、模块化和富俱乐部组织。
在全局水平上，发现所有参与者的脑功能网络均具有小世界特性。此外，三组之间在全局网络指标上存在显著的组间差异，如聚类系数、特征路径长度、归一化特征路径长度和小世界特性。在节点水平上，在伴有/不伴有认知功能下降的老年性聋患者中检测到几个具有异常中介中心性、度中心性、节点效率和节点局部效率的节点。在接受模块化分析的老年性聋患者中，发现额叶模块内模块连接和前额叶皮质下叶模块间模块连接发生了变化。老年性聋患者的富俱乐部节点发生了重组，但其之间的连接在组间无显著差异。
老年性聋患者表现出全脑功能网络的拓扑重组，伴有认知功能下降的老年性聋患者在这些拓扑特性上的变化比不伴有认知功能下降的患者更明显。老年性聋患者这些特性的异常变化可能通过调动额外的神经资源来补偿认知障碍。
