Large-scale cortex-core structure formation in brain organoids*

Brain organoids recapitulate several brain properties, including neuronal diversity. However,

do they recapitulate brain shape? Using a hydrodynamic description for cell nuclei as particles

interacting via an attractive field generated by the surrounding active cell cytoskeleton, we quantify

shape development in brain organoids. Regions of cell nuclei overdensity in the linear regime drive

the initial seeding for cortex-core structures, which emerge in the non-linear regime with elongated

cell nuclei and thus, cell shape, in the cortex. We then use an extended version of the buckling

without bending morphogenesis model to predict scalloped foliations/folds of the cortex in the

presence of nonlinearity due to elongated cells actively regulating strain. In addition to laying

new groundwork for the design of more familiar and less familiar brain shapes, our work provides an

intriguing quantitative connection with large-scale structure formation in the universe.