This study was aimed at delineating and comparing differences in clinical characteristics and brain activity between patients with low- and high-frequency tinnitus (LFT and HFT, respectively) using high-density electroencephalography (EEG). This study enrolled 3217 patients with subjective tinnitus who were divided into LFT ( Hz) and HFT (≥4000 Hz) groups. Data regarding medical history, Tinnitus Handicap Inventory, tinnitus matching, and hearing threshold were collected from all patients. Twenty tinnitus patients and 20 volunteers were subjected to 256-channel EEG, and neurophysiological differences were evaluated using standardized low-resolution brain electromagnetic tomography (sLORETA) source-localized EEG recordings. Significant differences in sex (), age (), laterality (), intensity (), tinnitus type (), persistent tinnitus (), average threshold (), and hearing loss () were observed between LFT and HFT groups. The tinnitus pitch only appeared to be correlated with the threshold of the worst hearing loss in the HFT group. Compared with the controls, the LFT group exhibited increased gamma power (), predominantly in the posterior cingulate cortex (PCC, BA31), whereas the HFT group had significantly decreased alpha1 power () in the angular gyrus (BA39) and auditory association cortex (BA22). Higher gamma linear connectivity between right BA39 and right BA41 was observed in the HFT group relative to controls (, ). Significant changes associated with increased gamma in the LFT group and decreased alpha1 in the HFT group indicate that tinnitus pitch is crucial for matching between the tinnitus and control groups. Differences of band frequency energy in brain activity levels may contribute to the clinical characteristics and internal tinnitus “spectrum” differences.

中文翻译：

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低频和高频耳鸣患者的临床特征和脑活动差异。

这项研究旨在使用高密度脑电图（EEG）描绘和比较低频和高频耳鸣（分别为LFT和HFT）患者之间的临床特征和大脑活动的差异。这项研究招募了3217名主观耳鸣患者，他们被分为LFT（ Hz）和HFT（≥4000Hz）组。从所有患者中收集有关病史，耳鸣残障库存，耳鸣匹配和听力阈值的数据。对20名耳鸣患者和20名志愿者进行了256通道脑电图检查，并使用标准化的低分辨率脑电磁层析成像（sLORETA）源定位的脑电图记录评估了神经生理学差异。性别上的重大差异（），年龄（），侧面（），强度（），耳鸣型（），持续性耳鸣（），平均阈值（）和听力损失（）在LFT和HFT组之间观察到。耳鸣音高似乎仅与HFT组最严重的听力损失阈值相关。与对照组相比，LFT组显示出更高的伽马强度（），主要位于扣带后皮层（PCC，BA31），而HFT组的alpha1功率明显降低（）在角回（BA39）和听觉皮层（BA22）中。在HFT组中，相对于对照，右BA39和右BA41之间观察到更高的伽马线性连接性（， ）。LFT组的γ升高和HFT组的α1降低相关的显着变化表明，耳鸣音高对于耳鸣和对照组之间的匹配至关重要。脑活动水平中频带能量的差异可能会导致临床特征和内部耳鸣“频谱”差异。