基于静息态fMRI的睡眠剥夺百分比振幅动态变化研究

Dynamic changes of percent amplitude of fluctuation in sleep deprivation based on resting-state fMRI

目的基于百分比振幅(percent amplitude of fluctuation,perAF)指标探讨睡眠剥夺(sleep deprivation,SD)过程中大脑自发功能活动的动态变化过程。材料与方法前瞻性招募36名健康志愿者分别于22时、24时、2时、4时及6时采集静息态功能磁共振成像(functional magnetic resonance imaging,fMRI)图像,同时利用斯坦福嗜睡量表(Stanford Sleepiness Scale,SSS)收集个体睡眠状态数据。应用单因素重复测量方差分析比较多时间全脑perAF值动态变化存在差异的脑区(P<0.05,FDR校正)。同时使用Pearson相关分析探讨差异脑区的perAF值动态变化与SSS分数的相关性。结果双侧丘脑、右侧中央前回、右侧顶上小叶、左内侧前额叶及右侧颞上回的perAF值存在显著的时间主效应(FDR校正,P<0.05,团块大小≥20体素),即上述脑区的perAF值在五个时间点中至少有两个时间点存在显著性差异,且发现22时与6时的右侧颞上回(r=0.36,P=0.03;r=0.37,P=0.02)及左内侧前额叶(r=0.33,P=0.05;r=0.41,P=0.01)perAF值与SSS分数呈显著正相关。结论默认模式网络、额顶注意力网络及丘脑的异常活动可能是SD过程中个体嗜睡程度增加及注意力下降的重要神经机制。

Objective:To investigate the dynamic changes of brain spontaneous functional activity during sleep deprivation(SD)based on the percent amplitude of fluctuation(perAF).Materials and Methods:A total of 36 healthy volunteers were recruited and their resting-state functional magnetic resonance imaging(fMRI)images were collected at 22:00 pm,24:00 pm,02:00 am,04:00 am,and 06:00am,respectively.Meanwhile,the Stanford Sleepiness Scale(SSS)was used to collect individual sleepiness data.One-way repeated measures ANOVA was used to compare the brain regions with different perAF dynamic changes over time(P<0.05,FDR correction).Pearson correlation analysis was used to explore the correlation between dynamic changes of perAF value and SSS score in different brain regions.Results:Significant time effects for perAF were found mainly in the bilateral thalamus,right precentral gyrus,right parietal lobule,left medial prefrontal lobe and right superior temporal gyrus(FDR correction,P<0.05,cluster size≥20 voxels).This means that perAF values in the above brain regions are significantly different at least two of the five time points.It was found that the right superior temporal gyrus(r=0.36,P=0.03;r=0.37,P=0.02)and left medial prefrontal lobe(r=0.33,P=0.05;r=0.41,P=0.01)at 22:00pm and 06:00 am was positively correlated with SSS scores.Conclusions:The abnormal activity of the default mode network,the frontoparietal attention network and the thalamus may be the important neural mechanism of increased sleepiness and decreased attention in individuals during sleep deprivation.