Verma Parul, Ranasinghe Kamalini, Prasad Janani, Cai Chang, Xie Xihe, Lerner Hannah, Mizuiri Danielle, Miller Bruce, Rankin Katherine, Vossel Keith, Cheung Steven W, Nagarajan Srikantan, Raj Ashish
Department of Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, CA, USA.
Memory and Aging Center, Department of Neurology, University of California San Francisco, San Francisco, CA, USA.
Res Sq. 2023 Nov 1:rs.3.rs-2579392. doi: 10.21203/rs.3.rs-2579392/v3.
Alzheimer's disease (AD) is the most common form of dementia, progressively impairing memory and cognition. While neuroimaging studies have revealed functional abnormalities in AD, how these relate to aberrant neuronal circuit mechanisms remains unclear. Using magnetoencephalography imaging we documented abnormal local neural synchrony patterns in patients with AD. To identify abnormal biophysical mechanisms underlying these abnormal electrophysiological patterns, we estimated the parameters of a spectral graph-theory model (SGM). SGM is an analytic model that describes how long-range fiber projections in the brain mediate the excitatory and inhibitory activity of local neuronal subpopulations. The long-range excitatory time scale was associated with greater deficits in global cognition and was able to distinguish AD patients from controls with high accuracy. These results demonstrate that long-range excitatory time scale of neuronal activity, despite being a global measure, is a key determinant in the spatiospectral signatures and cognition in AD.
阿尔茨海默病（AD）是最常见的痴呆形式，会逐渐损害记忆和认知能力。虽然神经影像学研究已经揭示了AD中的功能异常，但这些异常与异常神经元回路机制之间的关系仍不清楚。我们使用脑磁图成像记录了AD患者异常的局部神经同步模式。为了确定这些异常电生理模式背后的异常生物物理机制，我们估计了一个频谱图论模型（SGM）的参数。SGM是一个分析模型，描述了大脑中的长程纤维投射如何介导局部神经元亚群的兴奋和抑制活动。长程兴奋时间尺度与整体认知功能的更大缺陷相关，并且能够高精度地区分AD患者和对照组。这些结果表明，神经元活动的长程兴奋时间尺度尽管是一个全局指标，但却是AD时空频谱特征和认知的关键决定因素。
