We describe advances in the understanding of brain dynamics that are important for understanding the operation of the cerebral cortex in health and disease. In data from 1017 participants from the Human Connectome Project, we show that early visual and connected areas have low temporal variability of their functional connectivity. We show that a low temporal variability of the connectivity of cortical areas is related to high mean functional connectivity between those areas, and provide an account of how these dynamics arise. We then investigate how these concepts help to understand brain dynamics in mental disorders. We find that in both first episode and long-term schizophrenia, reduced functional connectivity of early visual and related temporal cortex areas is associated with increased temporal variability of the functional connectivity, consistent with decreased stability of attractor networks related to sensory processing. In ADHD, we find these functional connectivities are increased and their temporal variability is decreased, and relate this to increased engagement with visual sensory input as manifest in high screen time usage in ADHD. We further show that these differences in the dynamics of the cortex in schizophrenia, and ADHD can be related to differences in the functional connectivity of the specific sensory vs. association thalamic nuclei. These discoveries help to advance our understanding of cortical operation in health, and in some mental disorders.

我们描述了对大脑动力学的理解的进展，这对于理解大脑皮层在健康和疾病中的运作非常重要。在人类连接组项目 1017 名参与者的数据中，我们表明早期视觉和连接区域的功能连接的时间变异性较低。我们表明，皮质区域连接性的低时间变异性与这些区域之间的高平均功能连接性有关，并提供了这些动态如何产生的解释。然后我们研究这些概念如何帮助理解精神障碍中的大脑动力学。我们发现，在首发和长期精神分裂症中，早期视觉和相关颞叶皮层区域的功能连接性降低与功能连接性的时间变异性增加相关，这与与感觉处理相关的吸引子网络的稳定性降低一致。在多动症中，我们发现这些功能连接性增加，而它们的时间变异性减少，并将这与视觉感官输入的参与度增加联系起来，这在多动症患者的高屏幕时间使用中体现出来。我们进一步表明，精神分裂症和多动症中皮质动力学的这些差异可能与特定感觉与关联丘脑核的功能连接差异有关。这些发现有助于增进我们对健康和某些精神疾病中皮质运作的理解。