Introduction

Resting-state oscillatory activity has been extensively studied across a wide array of disorders. Establishing which spectrally- and spatially-specific oscillatory components exhibit test-retest reliability is essential to move the field forward. While studies have shown short-term reliability of MEG resting-state activity, no studies have examined test-retest reliability across an extended period of time to establish the stability of these signals, which is critical for reproducibility.

Methods

We examined 18 healthy adults age 23 - 61 who completed three visits across three years. For each visit, participants completed both a resting state MEG and structural MRI scan. MEG data were source imaged, and the cortical power in canonical frequency bands (delta, theta, alpha, beta, low gamma, high gamma) was computed. Intra-class correlation coefficients (ICC) were then calculated across the cortex for each frequency band.

Results

Over three years, power in the alpha and beta bands displayed the highest reliability estimates, while gamma showed the lowest estimates of three-year reliability. Spatially, delta, alpha, and beta all showed the highest degrees of reliability in the parietal cortex. Interestingly, the peak signal for each of these frequency bands was located outside of the parietal cortex, suggesting that reliability estimates were not solely dependent on the signal-to-noise ratio.

Conclusion

Oscillatory resting-state power in parietal delta, posterior beta, and alpha across most of the cortex are reliable across three years and future MEEG studies may focus on these measures for the development of specific markers.

中文翻译：

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MEG 静息态振荡电源的三年可靠性

介绍

静息态振荡活动已在各种疾病中得到广泛研究。确定哪些光谱和空间特定的振荡分量表现出重测可靠性对于推动该领域的发展至关重要。虽然研究表明 MEG 静息状态活动的短期可靠性，但没有研究检查过长时间的重测可靠性以确定这些信号的稳定性，这对于可重复性至关重要。

方法

我们检查了 18 名年龄在 23 至 61 岁之间的健康成年人，他们在三年内完成了三次就诊。对于每次访问，参与者都完成了静息状态 MEG 和结构 MRI 扫描。对 MEG 数据进行源成像，并计算规范频带（delta、theta、alpha、beta、低 gamma、高 gamma）中的皮层功率。然后计算每个频带的整个皮层的类内相关系数 (ICC)。

结果

在三年内，α 和β 波段的功率显示出最高的可靠性估计，而伽马显示出对三年可靠性的最低估计。在空间上，delta、alpha 和 beta 在顶叶皮质中都显示出最高程度的可靠性。有趣的是，这些频带中的每一个的峰值信号都位于顶叶皮层之外，这表明可靠性估计不仅仅取决于信噪比。

结论

顶叶三角洲、后 β 和 alpha 中大部分皮层的振荡静息状态功率在三年内是可靠的，未来的 MEEG 研究可能会集中在这些措施上，以开发特定的标志物。