Tianjin Key Laboratory of Cognitive Computing and Application, College of Intelligence and Computing, Tianjin University, Tianjin, People's Republic of China.
J Neural Eng. 2021 Sep 13;18(5). doi: 10.1088/1741-2552/ac20e7.
One of the most significant features of the human brain is that it can dynamically reconfigure itself to adapt to a changing environment. However, dynamic interaction characteristics of the brain networks in naturalistic scenes remain unclear.We used open-source functional magnetic resonance imaging (fMRI) data from 15 participants who underwent fMRI scans while watching an audio-visual movie 'Forrest Gump'. The community detection algorithm based on inter-subject functional correlation was used to study the time-varying functional networks only induced by the movie stimuli. The whole brain reconfiguration patterns were quantified by the temporal co-occurrence matrix that describes the probability of two brain regions engage in the same community (or putative functional module) across time and the time-varying brain modularity. Four graph metrics of integration, recruitment, spatio-temporal diversity and within-community normalised centrality were further calculated to summarise the brain network dynamic roles and hub features in their spatio-temporal topology.Our results suggest that the networks that were involved in attention and audio-visual information processing, such as the visual network, auditory network, and dorsal attention network, were considered to play a role of 'stable loners'. By contrast, 'unstable loner' networks such as the default mode network (DMN) and fronto-parietal network tended to interact more flexibly with the other networks. In addition, global brain network showed significant fluctuations in modularity. The 'stable loner' networks always maintained high functional connectivity (FC) strength while 'unstable loner' networks, especially the DMN, exhibited high intra- and inter-network FC only during a low modularity period. Finally, changes in brain modularity were significantly associated with variations in emotions induced by the movie.Our findings provide new insight for understanding the dynamic interaction characteristics of functional brain networks during naturalistic stimuli.
人脑的一个重要特征是它可以动态地重新配置自己以适应不断变化的环境。然而，自然场景下大脑网络的动态交互特征尚不清楚。我们使用了来自 15 名参与者的开源功能磁共振成像（fMRI）数据，这些参与者在观看视听电影《阿甘正传》时接受了 fMRI 扫描。我们使用基于主体间功能相关性的社区检测算法来研究仅由电影刺激引起的时变功能网络。通过描述两个脑区在时间上同时参与同一社区（或假定的功能模块）的概率的时变脑模块性和时间共现矩阵来量化全脑重构模式。进一步计算了四个整合、招募、时空多样性和社区内归一化中心性的图度量，以总结大脑网络在时空拓扑中的动态角色和枢纽特征。我们的研究结果表明，涉及注意力和视听信息处理的网络，如视觉网络、听觉网络和背侧注意网络，被认为发挥了“稳定的孤独者”的作用。相比之下，默认模式网络（DMN）和额顶网络等“不稳定的孤独者”网络往往与其他网络更灵活地相互作用。此外，全局脑网络的模块性显示出显著的波动。“稳定的孤独者”网络始终保持较高的功能连接（FC）强度，而“不稳定的孤独者”网络，特别是 DMN，仅在低模块性期间表现出较高的内和网络间 FC。最后，脑模块性的变化与电影引起的情绪变化显著相关。我们的研究结果为理解自然刺激下功能大脑网络的动态交互特征提供了新的见解。
