Department of Psychology, Drexel University, Philadelphia, PA 19104, USA; Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA.
Brain Behavior Laboratory, Department of Psychiatry, University of Pennsylvania, Philadelphia, PA 19104, USA.
Neuroimage. 2018 Feb 1;166:293-306. doi: 10.1016/j.neuroimage.2017.10.048. Epub 2017 Nov 7.
Adolescence is marked by rapid development of executive function. Mounting evidence suggests that executive function in adults may be driven by dynamic control of neurophysiological processes. Yet, how these dynamics evolve over adolescence and contribute to cognitive development is unknown. In a sample of 780 youth aged 8-22 yr (42.7% male) from the Philadelphia Neurodevelopment Cohort, we use a dynamic graph approach to extract activation states in BOLD fMRI data from 264 brain regions. We construct a graph in which each observation in time is a node and the similarity in brain states at two different times is an edge. Using this graphical approach, we identify two primary brain states reminiscent of intrinsic and task-evoked systems. We show that time spent in these two states is higher in older adolescents, as is the flexibility with which the brain switches between them. Increasing time spent in primary states and flexibility among states relates to increases in a complex executive accuracy factor score over adolescence. Flexibility is more positively associated with accuracy toward early adulthood. These findings suggest that brain state dynamics are associated with complex executive function across a critical period of adolescence.
青春期的特点是执行功能的快速发展。越来越多的证据表明，成年人的执行功能可能是由神经生理过程的动态控制驱动的。然而，这些动态如何随着青春期的发展而演变，并促进认知发展尚不清楚。在费城神经发育队列中，我们对 780 名年龄在 8 至 22 岁的青少年（42.7%为男性）进行了研究，使用动态图方法从 264 个脑区的 BOLD fMRI 数据中提取激活状态。我们构建了一个图，其中每个时间点的观测值都是一个节点，而两个不同时间点的脑状态相似性是一个边。使用这种图形方法，我们确定了两种主要的大脑状态，类似于内在和任务诱发系统。我们发现，在较年长的青少年中，这两种状态的持续时间更长，大脑在它们之间切换的灵活性也更高。在主要状态中花费的时间增加，以及状态之间的灵活性增加，与青春期期间复杂执行准确性因素得分的增加有关。灵活性与成年早期的准确性呈更积极的关联。这些发现表明，大脑状态的动态与青春期这一关键时期的复杂执行功能有关。
