Different functional networks exhibit distinct longitudinal trajectories throughout development, but the timeline of the dynamics of functional connectivity across the whole brain remains to be elucidated. Here we used resting-state fMRI to investigate the development of voxel-level changes in functional connectivity across the first six years of life. Globally, we found that developmental changes in functional connectivity are nonlinear with more changes during the first postnatal year than the second, followed by most significant changes from ages 2–4 and from ages 4–6. However, the overall global difference observed between the first and second year appears to have been driven by girls. Limbic and subcortical areas consistently demonstrated the most substantial changes, whereas primary sensory areas were the most stable. These patterns were consistent in full-term and preterm subgroups. Validation on randomly divided subsamples as well as in an independent cross-sectional sample revealed global patterns consistent with the main results. Overall, the derived developmental heatmaps reveal novel dynamics underlying functional circuit development during the first 6 years of life.

不同的功能网络在整个发育过程中表现出不同的纵向轨迹，但整个大脑功能连接动态的时间线仍有待阐明。在这里，我们使用静息态 fMRI 来研究生命前六年功能连接的体素水平变化的发展。在全球范围内，我们发现功能连接的发育变化是非线性的，出生后第一年的变化多于第二年，其次是 2-4 岁和 4-6 岁的最显着变化。然而，第一年和第二年之间观察到的总体全球差异似乎是由女孩造成的。边缘和皮层下区域始终表现出最实质性的变化，而初级感觉区域最稳定。这些模式在足月和早产亚组中是一致的。对随机划分的子样本以及独立横截面样本的验证揭示了与主要结果一致的全局模式。总体而言，衍生的发育热图揭示了生命前 6 年中功能电路发育的新动态。