Department of Neurology, Danish Dementia Research Centre (DDRC), Rigshospitalet, University of Copenhagen, Copenhagen, Denmark.
Norwegian National Advisory Unit on Ageing and Health (Ageing and Health), Vestfold Hospital Trust and Oslo University Hospital, Ullevaal, Oslo, Norway.
Brain Behav. 2020 Jun;10(6):e01630. doi: 10.1002/brb3.1630. Epub 2020 Apr 27.
Large-scale brain networks are disrupted in the early stages of Alzheimer's disease (AD). Electroencephalography microstate analysis, a promising method for studying brain networks, parses EEG signals into topographies representing discrete, sequential network activations. Prior studies indicate that patients with AD show a pattern of global microstate disorganization. We investigated whether any specific microstate changes could be found in patients with AD and mild cognitive impairment (MCI) compared to healthy controls (HC).
Standard EEGs were obtained from 135 HC, 117 patients with MCI, and 117 patients with AD from six Nordic memory clinics. We parsed the data into four archetypal microstates.
There was significantly increased duration, occurrence, and coverage of microstate A in patients with AD and MCI compared to HC. When looking at microstates in specific frequency bands, we found that microstate A was affected in delta (1-4 Hz), theta (4-8 Hz), and beta (13-30 Hz), while microstate D was affected only in the delta and theta bands. Microstate features were able to separate HC from AD with an accuracy of 69.8% and HC from MCI with an accuracy of 58.7%.
Further studies are needed to evaluate whether microstates represent a valuable disease classifier. Overall, patients with AD and MCI, as compared to HC, show specific microstate alterations, which are limited to specific frequency bands. These alterations suggest disruption of large-scale cortical networks in AD and MCI, which may be limited to specific frequency bands.
在阿尔茨海默病（AD）的早期阶段，大规模的大脑网络就会被打乱。脑电图微状态分析是一种研究大脑网络的很有前途的方法，它将 EEG 信号解析为代表离散、连续网络激活的地形图。先前的研究表明，AD 患者表现出全局微状态紊乱的模式。我们研究了与健康对照组（HC）相比，AD 和轻度认知障碍（MCI）患者是否存在特定的微状态变化。
从六个北欧记忆诊所中获得了 135 名 HC、117 名 MCI 患者和 117 名 AD 患者的标准 EEG。我们将数据解析为四个原型微状态。
AD 和 MCI 患者的微状态 A 的持续时间、出现率和覆盖率明显增加。当观察特定频率带中的微状态时，我们发现微状态 A 在 delta（1-4 Hz）、theta（4-8 Hz）和 beta（13-30 Hz）频段受到影响，而微状态 D 仅在 delta 和 theta 频段受到影响。微状态特征能够以 69.8%的准确率将 HC 与 AD 区分开来，以 58.7%的准确率将 HC 与 MCI 区分开来。
需要进一步研究以评估微状态是否代表有价值的疾病分类器。总体而言，与 HC 相比，AD 和 MCI 患者表现出特定的微状态改变，这些改变仅限于特定的频率带。这些改变表明 AD 和 MCI 中的大尺度皮质网络中断，可能仅限于特定的频率带。
