Department of Radiology, China-USA Neuroimaging Research Institute, The Second Affiliated Hospital and Yuying Children's Hospital, Wenzhou Medical University, Wenzhou, Zhejiang 325027, China.
Department of Pain, The Second Affiliated Hospital and Yuying Children's Hospital, Wenzhou Medical University, Wenzhou, Zhejiang 325027, China.
Neural Plast. 2018 May 29;2018:1672708. doi: 10.1155/2018/1672708. eCollection 2018.
Neuroimaging studies have demonstrated that major depressive disorder increases the risk of dementia in older individuals with mild cognitive impairment. We used resting-state functional magnetic resonance imaging to explore the intrinsic coupling patterns between the amplitude and synchronisation of low-frequency brain fluctuations using the amplitude of low-frequency fluctuations (ALFF) and the functional connectivity density (FCD) in 16 patients who had mild cognitive impairment with depressive symptoms (D-MCI) (mean age: 69.6 ± 6.2 years) and 18 patients with nondepressed mild cognitive impairment (nD-MCI) (mean age: 72.1 ± 9.7 years). Coupling was quantified as the correlations between the ALFF values and their associated FCDs. The results showed that the ALFF values in the D-MCI group were higher in the left medial prefrontal cortex (mPFC) and lower in the right precentral gyrus (preCG), and the FCD values were higher in the left medial temporal gyrus (MTG) than those in the nD-MCI group. Further, correlation analyses demonstrated that, in the D-MCI group, the mPFC was negatively correlated with the MTG. These findings may relate to the characteristics of mood disorders in patients with MCI, and they offer further insight into the neuropathophysiology of MCI with depressive symptoms.
神经影像学研究表明，在轻度认知障碍的老年个体中，重度抑郁症会增加痴呆的风险。我们使用静息态功能磁共振成像，通过低频振幅（ALFF）和功能连接密度（FCD）来探索有抑郁症状的轻度认知障碍患者（D-MCI，16 例，平均年龄 69.6±6.2 岁）和无抑郁症状的轻度认知障碍患者（nD-MCI，18 例，平均年龄 72.1±9.7 岁）之间低频脑波动幅度和同步性的内在耦合模式。耦合度通过 ALFF 值与其相关的 FCD 值之间的相关性来量化。结果表明，D-MCI 组的左侧内侧前额叶皮质（mPFC）的 ALFF 值较高，右侧中央前回（preCG）的 ALFF 值较低，左侧内侧颞叶（MTG）的 FCD 值较高。此外，相关分析表明，在 D-MCI 组中，mPFC 与 MTG 呈负相关。这些发现可能与 MCI 患者情绪障碍的特征有关，并为 MCI 伴抑郁症状的神经病理生理学提供了进一步的认识。
