Department of Radiology, The Affiliated Brain Hospital of Nanjing Medical University, Nanjing, China.
Department of Radiology, The Affiliated Drum Tower Hospital, Medical School of Nanjing University, Nanjing, China.
Brain Behav. 2023 Sep;13(9):e3169. doi: 10.1002/brb3.3169. Epub 2023 Aug 3.
Amnestic mild cognitive impairment (aMCI) is considered to be the prodromal stage of Alzheimer's disease (AD). The precuneus (PCUN) may be an imaging marker for monitoring the progression of AD. Meanwhile, cognitive impairment in AD patients is closely related to functional connectivity (FC) changes in the salience network (SN). We hypothesize that there are specific neuroimaging biomarkers in the SN and that FC changes in aMCI patients after repetitive transcranial magnetic stimulation (rTMS) intervention are associated with cognitive function. The purpose of this study was to first investigate the pattern of functional changes in aMCI patients and healthy controls (HCs) and then compare the functional changes in aMCI patients before and after rTMS targeting to PCUN and its correlation with cognitive function.
Thirty-six HCs and 61 aMCIs were recruited for our study. Eleven people in the aMCI group received rTMS intervention 5 days a week for 4 weeks. Using the right anterior insula as the seed-of-interest, we first compared FC changes in HC and aMCI patients and then compared cognitive function in aMCI patients before and after rTMS. The above is the functional connection analysis of seed-to-voxel. Moreover, we investigated the FC changes in aMCI patients after rTMS intervention and its correlation with cognitive function.
Compared with HC, the aMCI group showed altered FC in bilateral parahippocampal gyrus, bilateral inferior parietal lobule, left middle frontal gyrus, and left middle temporal gyrus. Moreover, rTMS at PCUN improved the cognitive function of aMCI patients, which was related to the altered FC in posterior cerebellar lobes (CPL).
Our findings suggest that rTMS targeting PCUN is a promising, noninvasive approach to ameliorating cognitive dysfunction in aMCI patients, and that this cognitive improvement is accompanied by brain connectivity modulation.
遗忘型轻度认知障碍（aMCI）被认为是阿尔茨海默病（AD）的前驱阶段。楔前叶（PCUN）可能是监测 AD 进展的影像学标志物。同时，AD 患者的认知障碍与突显网络（SN）的功能连接（FC）变化密切相关。我们假设 SN 中有特定的神经影像学生物标志物，并且 rTMS 干预后 aMCI 患者的 FC 变化与认知功能相关。本研究旨在首先研究 aMCI 患者和健康对照（HC）的功能变化模式，然后比较 rTMS 靶向 PCUN 前后 aMCI 患者的功能变化及其与认知功能的相关性。
我们招募了 36 名 HC 和 61 名 aMCI 患者参加我们的研究。aMCI 组中有 11 人每周接受 5 天 rTMS 干预，持续 4 周。我们使用右侧前岛叶作为感兴趣的种子，首先比较了 HC 和 aMCI 患者的 FC 变化，然后比较了 rTMS 前后 aMCI 患者的认知功能。以上是种子到体素的功能连接分析。此外，我们还研究了 rTMS 干预后 aMCI 患者的 FC 变化及其与认知功能的相关性。
与 HC 相比，aMCI 组双侧海马旁回、双侧下顶叶、左额中回和左颞中回的 FC 发生改变。此外，PCUN 的 rTMS 改善了 aMCI 患者的认知功能，这与小脑后叶（CPL）的 FC 改变有关。
我们的研究结果表明，rTMS 靶向 PCUN 是改善 aMCI 患者认知功能障碍的一种有前途的非侵入性方法，这种认知改善伴随着脑连接的调节。
