Computational model of NC migration. (A) Schematic embryo during NCC migration in the Xenopus head. (B–D) Cell interactions in the CPM: CIL (B), CoA (C), and dorsal and lateral confinements (D). (E) CPM configurations for versions of NC migration in constrained geometries with and without CIL and CoA. (F and J) Migration efficiencies. Error bars: min-max values, boxes: quartiles; central value: median; n = 50 simulations. Significance compared with relevant control, where significance bars (purple) compare data from the same conditions. (G) CPM configuration in unconstrained geometry. (H) Rules of the DEM model of NCC migration. (I) Configuration of the DEM model with and without confinement. ***, P < 0.001; ns, not significant.