孤独症谱系障碍儿童脑磁图静息态伽马频带脑功能网络探析

目的:研究孤独症谱系障碍(ASD)儿童静息态脑磁图伽马频带的脑功能网络特征。方法:ASD儿童6名,健康对照9名。采集静息态脑磁图信号和磁共振数据,在信号源水平进行伽马频带信号在大脑皮层的功率谱密度分析,并计算相位转移熵,构建脑网络,用于患儿组和对照组比较。结果:在脑网络节点激活程度方面,与对照组相比,患儿的伽马频带激活程度偏低(均P<0.05),受到显著抑制的脑区主要集中在双侧额叶、双侧颞叶和双侧岛叶,少量分布在右侧边缘叶及右侧顶叶。在脑网络节点间信息传递方面,信息汇集点存在组间差异(均P<0.05),患儿组为左侧角回中部,对照组为右侧枕中回腹部和左侧舌回后部。另外,信息发散点也有组间差异(均P<0.05),患儿组为右侧前眶额回和右侧岛盖部上部以及左侧梭状回前部,对照组则无显著的信息发放核心脑区。结论:ASD儿童大脑静息态伽马频带激活程度较低,提示患儿大脑存在兴奋-抑制失衡。ASD儿童伽马频带脑网络中,信息接收和发放的核心脑区分布模式与对照组存在差异,信息发放失衡。

Magnetoencephalogram based exploratory analysis of gamma band functional brain networks in children with autism spectrum disorder

Objective:To investigate the brain functional network characteristics of resting gamma band in children with autism spectrum disorder by magnetoencephalogram.Methods:Six children with autism and 9 healthy controls were enrolled in this study.The resting-state magnetoencephalogram signal and magnetic resonance data were collected,and the power spectral density analysis of the gamma bands signal in the cerebral cortex was performed at the signal source level,and the phase transfer entropy was calculated to construct the brain network for comparison between the ASD group and the control group.Results:In terms of the activation degree of brain network nodes,compared with the control group,the gamma-band activation degree was reduced in ASD children.The significantly inhibited brain regions(P<0.05)mainly distributed in bilateral frontal lobes,bilateral temporal lobes and bilateral insular lobes,with a small amount distributed in right limbic system and right parietal lobe.In terms of information flow between brain network nodes,there were differences in information receiving points between two groups.The ASD group consisted of the middle left angulargyrus,while the control group consisted of the middle right occipital gyrus and the left posterior lingualgyrus.In addition,there were also differences in information driving points between two groups.The ASD group consisted of the right anterior orbitofrontalgyrus,the right upper insulargyrus,and the left anterior fusiformgyrus,while the control group had no significant information distribution in the corebrain region.Conclusion:The activation degree of the resting-state gamma band in the brains of autistic children is lower,suggesting that there is an excitation-inhibition imbalance in the brain of autistic children.In the gamma-band brain network of autistic children,the distribution pattern of the corebrain regions of information receiving and driving is different from that of the control group,resulting in an imbalance of information driving.