Grow2Fold: mapping heterogeneous developmental growth to human brain folding

Cortical folding emerges through complex developmental processes, yet what organizes these processes into the characteristic folding patterns of the human brain remains unclear. Here, we developed an imaging-informed whole-brain modeling framework, Grow2Fold, that integrates developmental cortical regionalization, quantitative growth characterization, and mechanics-guided simulation to investigate how cortical growth shapes brain folding patterns. Using 836 fetal and neonatal MRI sessions from 747 participants spanning 21-45 postmenstrual weeks, we identified a reproducible and hierarchical spatiotemporal organization of cortical expansion characterized by coordinated regional growth trajectories. Rapid expansion occurs earlier around peri-central territories and progressively shifts toward frontal, parietal, and temporal association cortices. We encoded these imaging-derived trajectories into region- and age-specific growth laws and incorporated them into anatomically realistic whole-brain mechanical models. The resulting simulations recapitulate major sulcal landmarks and characteristic folding development across global and regional morphological measures. Comparing regional and uniform growth, we find that differential growth drives cortical instability, while heterogeneous developmental growth organizes this instability into anatomically recognizable folding patterns. Combined with subject-specific anatomy, these population-informed growth laws reproduce individualized longitudinal folding trajectories. Together, our results identify spatiotemporally patterned developmental growth as a key spatial constraint on cortical morphogenesis and establish a quantitative bridge from developmental imaging, through mechanical instability, to anatomically organized folding.