Working memory (WM) is a crucial cognitive process and its disruption is among the earliest symptoms of Alzheimer’s disease. While alterations of the neuronal processes underlying WM have been evidenced in mild cognitive impairment (MCI), scarce literature is available in subjective cognitive decline (SCD). We used magnetoencephalography during a WM task performed by MCI [Formula: see text], SCD [Formula: see text] and healthy elders [Formula: see text] to examine group differences during the maintenance period (0–4000[Formula: see text]ms). Data were analyzed using time–frequency analysis and significant oscillatory differences were localized at the source level. Our results indicated significant differences between groups, mainly during the early maintenance (250–1250[Formula: see text]ms) in the theta, alpha and beta bands and in the late maintenance (2750–3750[Formula: see text]ms) in the theta band. MCI showed lower local synchronization in fronto-temporal cortical regions in the early theta–alpha window relative to controls [Formula: see text] and SCD [Formula: see text], and in the late theta window relative to controls [Formula: see text] and SCD [Formula: see text]. Early theta–alpha power was significantly correlated with memory scores [Formula: see text] and late theta power was correlated with task performance [Formula: see text] and functional activity scores [Formula: see text]. In the early beta window, MCI showed reduced power in temporo-posterior regions relative to controls [Formula: see text] and SCD [Formula: see text]. Our results may suggest that these alterations would reflect that memory-related networks are damaged.

中文翻译：

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轻度认知障碍和主观认知衰退中工作记忆维持期间的时空振荡模式

工作记忆 (WM) 是一个重要的认知过程，它的破坏是阿尔茨海默病的最早症状之一。虽然 WM 背后的神经元过程的改变已在轻度认知障碍 (MCI) 中得到证实，但关于主观认知衰退 (SCD) 的文献却很少。我们在 MCI [公式：见文本]、SCD [公式：见文本] 和健康长者 [公式：见文本] 执行的 WM 任务期间使用脑磁图检查维持期间的组差异（0-4000 [公式：见文本） ]小姐）。使用时频分析对数据进行了分析，并且显着的振荡差异定位在源级别。我们的结果表明组间存在显着差异，主要是在 theta 的早期维护期间（250–1250 [公式：见文本] ms），alpha 和 beta 波段以及后期维护（2750–3750[公式：见文本]ms）在 theta 波段。MCI 在相对于对照 [公式：见文本] 和 SCD [公式：见文本] 和相对于对照 [公式：见文本] 的晚期 theta 窗口中，额颞叶皮质区域的局部同步性较低] 和 SCD [公式：见正文]。早期 theta-alpha 功率与记忆分数 [公式：见文本] 显着相关，晚期 theta 功率与任务表现 [公式：见文本] 和功能活动分数 [公式：见文本] 相关。在早期的 beta 窗口中，相对于对照 [公式：参见文本] 和 SCD [公式：参见文本]，MCI 在颞后部区域的功率降低。我们的结果可能表明，这些改变将反映与记忆相关的网络已损坏。