Baker Simon T E, Lubman Dan I, Yücel Murat, Allen Nicholas B, Whittle Sarah, Fulcher Ben D, Zalesky Andrew, Fornito Alex
Turning Point, Eastern Health and Eastern Health Clinical School, Monash University, Victoria 3065, Australia, Monash Clinical and Imaging Neuroscience, School of Psychological Sciences and Monash Biomedical Imaging, Monash University, Victoria 3168, Australia, Melbourne Neuropsychiatry Centre, Department of Psychiatry, The University of Melbourne and Melbourne Health, Victoria 3053, Australia.
Turning Point, Eastern Health and Eastern Health Clinical School, Monash University, Victoria 3065, Australia.
J Neurosci. 2015 Jun 17;35(24):9078-87. doi: 10.1523/JNEUROSCI.5043-14.2015.
The human brain undergoes substantial development throughout adolescence and into early adulthood. This maturational process is thought to include the refinement of connectivity between putative connectivity hub regions of the brain, which collectively form a dense core that enhances the functional integration of anatomically distributed, and functionally specialized, neural systems. Here, we used longitudinal diffusion magnetic resonance imaging to characterize changes in connectivity between 80 cortical and subcortical anatomical regions over a 2 year period in 31 adolescents between the ages of 15 and 19 years. Connectome-wide analysis indicated that only a small subset of connections showed evidence of statistically significant developmental change over the study period, with 8% and 6% of connections demonstrating decreased and increased structural connectivity, respectively. Nonetheless, these connections linked 93% and 90% of the 80 regions, respectively, pointing to a selective, yet anatomically distributed pattern of developmental changes that involves most of the brain. Hub regions showed a distinct tendency to be highly connected to each other, indicating robust "rich-club" organization. Moreover, connectivity between hubs was disproportionately influenced by development, such that connectivity between subcortical hubs decreased over time, whereas frontal-subcortical and frontal-parietal hub-hub connectivity increased over time. These findings suggest that late adolescence is characterized by selective, yet significant remodeling of hub-hub connectivity, with the topological organization of hubs shifting emphasis from subcortical hubs in favor of an increasingly prominent role for frontal hub regions.
人类大脑在整个青春期直至成年早期都会经历显著的发育。这种成熟过程被认为包括大脑假定的连接枢纽区域之间连接的优化，这些区域共同形成一个密集核心，增强了解剖学上分布且功能专门化的神经系统的功能整合。在此，我们使用纵向扩散磁共振成像来表征31名年龄在15至19岁之间的青少年在两年时间里80个皮质和皮质下解剖区域之间连接的变化。全脑连接组分析表明，在研究期间，只有一小部分连接显示出具有统计学意义的发育变化迹象，分别有8%和6%的连接显示出结构连接性降低和增加。尽管如此，这些连接分别连接了80个区域中的93%和90%，表明发育变化具有选择性但在解剖学上呈分布状态，涉及大脑的大部分区域。枢纽区域表现出彼此高度连接的明显趋势，表明存在强大的“富俱乐部”组织。此外，枢纽之间的连接受到发育的影响不成比例，以至于皮质下枢纽之间的连接随着时间推移而减少，而额叶 - 皮质下和额叶 - 顶叶枢纽 - 枢纽连接随着时间推移而增加。这些发现表明，青春期后期的特征是枢纽 - 枢纽连接的选择性但显著的重塑，枢纽的拓扑组织将重点从皮质下枢纽转移，有利于额叶枢纽区域发挥越来越突出的作用。
