The brain's dynamic spontaneous neural activity is significant in supporting cognition; however, how brain dynamics go awry in subjective cognitive decline (SCD) and mild cognitive impairment (MCI) remains unclear. Thus, the current study aimed to investigate the dynamic amplitude of low-frequency fluctuation (dALFF) alterations in patients at high risk for Alzheimer's disease and to explore its correlation with clinical cognitive assessment scales, to identify an early imaging sign for these special populations. A total of 152 participants, including 72 SCD patients, 44 MCI patients and 36 healthy controls (HCs), underwent a resting-state functional magnetic resonance imaging and were assessed with various neuropsychological tests. The dALFF was measured using sliding-window analysis. We employed canonical correlation analysis (CCA) to examine the bi-multivariate correlations between neuropsychological scales and altered dALFF among multiple regions in SCD and MCI patients. Compared to those in the HC group, both the MCI and SCD groups showed higher dALFF values in the right opercular inferior frontal gyrus (voxel P < .001, cluster P < .05, correction). Moreover, the CCA models revealed that behavioural tests relevant to inattention correlated with the dALFF of the right middle frontal gyrus and right opercular inferior frontal gyrus, which are involved in frontoparietal networks (R = .43, P = .024). In conclusion, the brain dynamics of neural activity in frontal areas provide insights into the shared neural basis underlying SCD and MCI.

中文翻译：

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阿尔茨海默病高危个体低频波动动态幅度的改变

大脑的动态自发神经活动对于支持认知具有重要意义；然而，大脑动力学如何导致主观认知衰退（SCD）和轻度认知障碍（MCI）仍不清楚。因此，本研究旨在调查阿尔茨海默病高危患者低频波动（dALFF）变化的动态幅度，并探讨其与临床认知评估量表的相关性，以确定这些特殊人群的早期影像学征兆。总共 152 名参与者，包括 72 名 SCD 患者、44 名 MCI 患者和 36 名健康对照 (HC)，接受了静息态功能磁共振成像，并接受了各种神经心理学测试的评估。使用滑动窗口分析测量 dALFF。我们采用典型相关分析 (CCA) 来检查 SCD 和 MCI 患者多个区域的神经心理学量表与 dALFF 改变之间的双多元相关性。与 HC 组相比，MCI 和 SCD 组的右侧鳃盖下额回的 dALFF 值较高（体素P  < .001，簇P  < .05，校正）。此外，CCA 模型显示，与注意力不集中相关的行为测试与参与额顶网络的右侧额中回和右侧额下回的 dALFF 相关（R = .43，P  = .024）。总之，额叶区域神经活动的大脑动力学提供了对 SCD 和 MCI 共同神经基础的见解。