Wang Li, Kong Qingmei, Li Ke, Su Yunai, Zeng Yawei, Zhang Qinge, Dai Wenji, Xia Mingrui, Wang Gang, Jin Zhen, Yu Xin, Si Tianmei
Peking University Sixth Hospital (Institute of Mental Health), National Clinical Research Center for Mental Disorders & Key Laboratory of Mental Health, Ministry of Health (Peking University), Bejing, China.
Department of Radiology, 306 Hospital of People's Liberation Army, Beijing, China.
Neurosci Lett. 2016 Feb 12;614:105-11. doi: 10.1016/j.neulet.2016.01.012. Epub 2016 Jan 12.
We conducted this fMRI study to examine whether the alterations in amplitudes of low-frequency oscillation (LFO) of major depressive disorder (MDD) patients were frequency dependent.
The LFO amplitudes (as indexed by amplitude of low-frequency fluctuation [ALFF] and fractional ALFF [fALFF]) within 4 narrowly-defined frequency bands (slow-5: 0.01-0.027Hz, slow-4: 0.027-0.073Hz, slow-3: 0.073-0.198Hz, and slow-2: 0.198-0.25Hz) were computed using resting-state fMRI data of 35 MDD patients and 32 healthy subjects. Repeated-measures analysis of variance (ANOVA) was performed on ALFF and fALFF both within the low frequency bands of slow-4 and slow-5 and within all of the four bands.
We observed significant main effects of group and frequency on ALFF and fALFF in widely distributed brain regions. Importantly, significant group and frequency interaction effects were observed in the ventromedial prefrontal cortex, inferior frontal gyrus, precentral gyrus, in a left-sided fashion, the bilateral posterior cingulate and precuneus, during ANOVA both within slow-4 and slow-5 bands and within all the frequency bands.
The results suggest that the alterations of LFO amplitudes in specific brain regions in MDD patients could be more sensitively detected in the slow-5 rather than the slow-4 bands. The findings may provide guidance for the frequency choice of future resting-state fMRI studies of MDD.
我们开展这项功能磁共振成像（fMRI）研究，以检验重度抑郁症（MDD）患者低频振荡（LFO）幅度的改变是否与频率有关。
使用35例MDD患者和32名健康受试者的静息态fMRI数据，计算4个窄带定义频率范围内（慢波5：0.01 - 0.027Hz，慢波4：0.027 - 0.073Hz，慢波3：0.073 - 0.198Hz，慢波2：0.198 - 0.25Hz）的LFO幅度（以低频波动幅度[ALFF]和ALFF分数[fALFF]为指标）。对慢波4和慢波5的低频带内以及所有四个频带内的ALFF和fALFF进行重复测量方差分析（ANOVA）。
我们在广泛分布的脑区观察到组和频率对ALFF和fALFF有显著的主效应。重要的是，在慢波4和慢波5频段以及所有频段的ANOVA过程中，在内侧前额叶皮层、额下回、中央前回，左侧的双侧后扣带回和楔前叶观察到显著的组和频率交互效应。
结果表明，MDD患者特定脑区LFO幅度的改变在慢波5频段比慢波4频段能更敏感地检测到。这些发现可能为未来MDD静息态fMRI研究的频率选择提供指导。
