Department of Occupational Therapy and Graduate Institute of Behavioral Sciences, Chang Gung University, Taoyuan, Taiwan.
Laboratory of Brain Imaging and Neural Dynamics (BIND Lab), Chang Gung University, Taoyuan, Taiwan.
Psychophysiology. 2021 Jun;58(6):e13820. doi: 10.1111/psyp.13820. Epub 2021 Apr 1.
The cross-sectional identification of subjective cognitive decline (SCD) in cognitively normal adults is particularly important for the early effective prevention or intervention of the future development of mild cognitive impairments (MCI) or Alzheimer's disease (AD). A pre-attentive neurophysiological signal that reflects the brain's ability to detect the changes of the environment is called mismatch negativity (MMN) or its magnetic counterpart (MMNm). It has been shown that patients with MCI or AD demonstrate reduced MMN/MMNm responses, while the exact profile of MMN/MMNm in SCD is substantially unknown. We applied magnetoencephalographic recordings to interrogate MMNm activities in healthy controls (HC, n = 29) and individuals with SCD (n = 26). Furthermore, we analyzed gray matter (GM) volumes in the MMNm-related regions through voxel-based morphometry and performed apolipoprotein E4 (APOE4) genotyping for all the participants. Our results showed that there were no significant differences in GM volume and proportions of APOE4 carriers between HC and SCD groups. However, individuals with SCD exhibited weakened z-corrected MMNm responses in the left inferior parietal lobule and right inferior frontal gyrus (IFG) as compared to HC. Based on the regions showing significant between-group differences, z-corrected MMNm amplitudes of the right IFG significantly correlated with the memory performance among the SCD participants. Our data suggest that neurophysiological changes of the brain, as indexed by MMNm, precede structural atrophy in the individuals with SCD compared to those without SCD.
横断面识别认知正常成年人的主观认知下降（SCD）对于早期有效预防或干预轻度认知障碍（MCI）或阿尔茨海默病（AD）的未来发展尤为重要。一种反映大脑检测环境变化能力的非注意神经生理信号称为失匹配负波（MMN）或其磁场对应物（MMNm）。已经表明，MCI 或 AD 患者的 MMN/MMNm 反应减少，而 SCD 中 MMN/MMNm 的确切特征尚不清楚。我们应用脑磁图记录来探究健康对照组（HC，n=29）和 SCD 个体（n=26）的 MMNm 活动。此外，我们通过基于体素的形态计量学分析了 MMNm 相关区域的灰质（GM）体积，并对所有参与者进行了载脂蛋白 E4（APOE4）基因分型。我们的结果表明，HC 和 SCD 组之间 GM 体积和 APOE4 携带者的比例没有显著差异。然而，与 HC 相比，SCD 个体在左顶下小叶和右额下回（IFG）的 z 校正 MMNm 反应较弱。基于表现出显著组间差异的区域，右 IFG 的 z 校正 MMNm 幅度与 SCD 参与者的记忆表现显著相关。我们的数据表明，与没有 SCD 的个体相比，SCD 个体的大脑神经生理变化，如 MMNm 所示，先于结构萎缩。
