基于固定点分析揭示衰老、听力损失和耳鸣对人类听觉系统白质的影响。
The effect of aging, hearing loss, and tinnitus on white matter in the human auditory system revealed with fixel-based analysis.
作者信息
Svobodová Veronika, Profant Oliver, Škoch Antonín, Tintěra Jaroslav, Tóthová Diana, Chovanec Martin, Čapková Dora, Syka Josef
机构信息
Department of Auditory Neuroscience, Institute of Experimental Medicine of the Czech Academy of Sciences, Prague, Czechia.
Department of Otorhinolaryngology and Head and Neck Surgery, 1st Faculty of Medicine, Charles University in Prague, University Hospital Motol, Prague, Czechia.
出版信息
Front Aging Neurosci. 2024 Jan 9;15:1283660. doi: 10.3389/fnagi.2023.1283660. eCollection 2023.
INTRODUCTION
Aging negatively influences the structure of the human brain including the white matter. The objective of our study was to identify, using fixel-based morphometry, the age induced changes in the pathways connecting several regions of the central auditory system (inferior colliculus, Heschl's gyrus, planum temporale) and the pathways connecting these structures with parts of the limbic system (anterior insula, hippocampus and amygdala). In addition, we were interested in the extent to which the integrity of these pathways is influenced by hearing loss and tinnitus.
METHODS
Tractographic data were acquired using a 3 T MRI in 79 volunteers. The participants were categorized into multiple groups in accordance with their age, auditory thresholds and tinnitus status. Fixel-based analysis was utilized to identify alterations in the subsequent three parameters: logarithm of fiber cross-section, fiber density, fiber density and cross-section. Two modes of analysis were used: whole brain analysis and targeted analysis using fixel mask, corresponding to the pathways connecting the aforementioned structures.
RESULTS
A significantly negative effect of aging was present for all fixel-based metrics, namely the logarithm of the fiber cross-section, (7 % fixels in whole-brain, 14% fixels in fixel mask), fiber density (5 % fixels in whole-brain, 15% fixels in fixel mask), fiber density and cross section (7 % fixels in whole-brain, 19% fixels in fixel mask). Expressed age-related losses, exceeding 30% fixels, were particularly present in pathways connecting the auditory structures with limbic structures. The effect of hearing loss and/or tinnitus did not reach significance.
CONCLUSIONS
Our results show that although an age-related reduction of fibers is present in pathways connecting several auditory regions, the connections of these structures with limbic structures are even more reduced. To what extent this fact influences the symptoms of presbycusis, such as decreased speech comprehension, especially in noise conditions, remains to be elucidated.
引言
衰老对包括白质在内的人类大脑结构产生负面影响。我们研究的目的是使用基于固定点的形态测量法，确定年龄引起的连接中枢听觉系统多个区域（下丘、颞横回、颞平面）的通路以及连接这些结构与边缘系统部分区域（前岛叶、海马体和杏仁核）的通路的变化。此外，我们还关注这些通路的完整性受听力损失和耳鸣影响的程度。
方法
在79名志愿者中使用3T磁共振成像获取纤维束成像数据。参与者根据年龄、听觉阈值和耳鸣状态被分为多个组。采用基于固定点的分析来识别以下三个参数的变化：纤维横截面的对数、纤维密度、纤维密度和横截面。使用了两种分析模式：全脑分析和使用固定点掩码的靶向分析，对应于连接上述结构的通路。
结果
对于所有基于固定点的指标，即纤维横截面的对数（全脑7%的固定点，固定点掩码14%的固定点）、纤维密度（全脑5%的固定点，固定点掩码15%的固定点）、纤维密度和横截面（全脑7%的固定点，固定点掩码19%的固定点），衰老均有显著的负面影响。超过30%固定点的与年龄相关的损失尤其出现在连接听觉结构与边缘结构的通路中。听力损失和/或耳鸣的影响未达到显著水平。
结论
我们的结果表明，尽管在连接多个听觉区域的通路中存在与年龄相关的纤维减少，但这些结构与边缘结构的连接减少得更多。这一事实在多大程度上影响老年性聋的症状，如言语理解能力下降，尤其是在噪声环境中，仍有待阐明。
Zotero 插件