Laboratory of Integrative Neuroscience and Cognition, Department of Neuroscience, Georgetown University Medical Center, 3970 Reservoir Rd NW, Washington, DC, 20057, USA.
Sci Rep. 2023 Apr 7;13(1):5746. doi: 10.1038/s41598-023-32599-0.
Tinnitus is the perception of a ringing, buzzing or hissing sound "in the ear" without external stimulation. Previous research has demonstrated changes in resting-state functional connectivity in tinnitus, but findings do not overlap and are even contradictory. Furthermore, how altered functional connectivity in tinnitus is related to cognitive abilities is currently unknown. Here we investigated resting-state functional connectivity differences between 20 patients with chronic tinnitus and 20 control participants matched in age, sex and hearing loss. All participants underwent functional magnetic resonance imaging, audiometric and cognitive assessments, and filled in questionnaires targeting anxiety and depression. Significant differences in functional connectivity between tinnitus patients and control participants were not obtained. However, we did find significant associations between cognitive scores and functional coupling of the default mode network and the precuneus with the superior parietal lobule, supramarginal gyrus, and orbitofrontal cortex. Further, tinnitus distress correlated with connectivity between the precuneus and the lateral occipital complex. This is the first study providing evidence for disruptions of default mode network and precuneus coupling that are related to cognitive dysfunctions in tinnitus. The constant attempt to decrease the tinnitus sensation might occupy certain brain resources otherwise available for concurrent cognitive operations.
耳鸣是指没有外部刺激时在“耳朵”中感知到的嗡嗡声、嘶嘶声或咝咝声。先前的研究已经证明了耳鸣的静息态功能连接发生了变化，但研究结果并不重叠，甚至相互矛盾。此外，耳鸣中改变的功能连接与认知能力有何关系目前尚不清楚。在这里，我们调查了 20 名慢性耳鸣患者和 20 名年龄、性别和听力损失相匹配的对照组参与者之间的静息态功能连接差异。所有参与者都接受了功能磁共振成像、听力和认知评估，并填写了针对焦虑和抑郁的问卷。耳鸣患者和对照组之间没有发现功能连接的显著差异。然而，我们确实发现认知评分与默认模式网络和楔前叶与顶上小叶、缘上回和眶额皮层之间的功能耦合之间存在显著关联。此外，耳鸣困扰与楔前叶和外侧枕叶复合体之间的连接有关。这是第一项提供证据表明，默认模式网络和楔前叶连接中断与耳鸣中的认知功能障碍有关的研究。持续试图减少耳鸣感觉可能会占用某些本可用于同时进行认知操作的大脑资源。
