单侧耳聋中结构和功能网络的大脑半球不对称性的同步改变

文献信息

中文摘要

背景： 大脑结构和功能的不对称性对高级认知能力至关重要，并受到两个半球接收和处理信息的影响。单侧耳聋（SSD）是一种常见的临床病症，代表了部分感觉剥夺的极端情况。然而，单侧听力损失如何影响大脑半球不对称性仍知之甚少。方法：为了解决这个问题，我们招募了35名语后起病长期SSD患者（19名左侧SSD/16名右侧SSD）和18名正常听力对照者，收集了他们的结构（弥散张量成像）和静息态功能磁共振成像数据，进行了确定性纤维束追踪和功能连接分析，以构建白质结构网络和静息态功能网络，并检查了他们在多尺度层级网络（即全局、模块和节点网络）中拓扑不对称性的可塑性改变。结果：我们的结果揭示了单侧听力剥夺后结构和功能网络半球不对称性均向右偏移，尤其是在右侧SSD患者中，这与右半球（RH）拓扑属性的增加有关，表明右半球的连接效率提高。此外，深入的模块和节点分析显示，重组后的全局不对称性主要由感觉和多感觉整合区域（即颞叶、枕叶和皮层下核团）的不对称性改变驱动。结论：总之，这些发现表明SSD诱导了结构和功能网络大脑不对称性的同步重组。此外，这些发现表明，更有效地利用非优势右半球可能是部分感觉剥夺后的一种重要代偿模式。

英文摘要

Brain asymmetry of structure and function, which is critical for high-level cognitive abilities, is influenced by the information received and processed in the two hemispheres. Single-sided deafness (SSD) is a prevalent clinical condition, representing an extreme case of partial sensory deprivation. However, how unilateral hearing loss affects brain hemispheric asymmetry remains poorly understood. To address this issue, we recruited 35 postlingual-onset long-term SSD patients (19/16 left/right SSD) and 18 normal hearing controls, collected their structural (diffusion tensor imaging) and resting-state functional magnetic resonance imaging data, performed deterministic fiber tractography and functional connectivity analysis to construct white matter structural and resting-state functional networks, and examined plastic alterations in their topological asymmetry across multiscale hierarchical networks (i.e., global, modular, and nodal networks). Our results revealed a rightward shift in hemispheric asymmetry for both structural and functional networks after unilateral hearing deprivation, particularly in patients with right SSD, which was related to an increase in topological properties of the right hemisphere (RH), suggesting improved connection efficiency of the RH. Moreover, in-depth modular and nodal analyses revealed that reorganized global asymmetry was driven mainly by altered asymmetry in sensory and multisensory integration areas (i.e., the temporal lobe, the occipital lobe, and subcortical nuclei). Together, these findings indicate that SSD induces concurrent reorganization in brain asymmetry of both structural and functional networks. Furthermore, these findings suggest that more efficient utilization of the nondominant RH may be an important compensatory pattern after partial sensory deprivation.