Figure 9.

Combined effects of neurogenesis and axonogenesis on the convex convolution patterns of cerebral cortex. Black arrows highlight regions where denser axons are connected; these regions are thus endowed with higher stiffness. The shell growth speed in intermittent sections (near the black arrows) is faster than the other shell regions and core. The growth speed ratio g_f/g_c between axons and the core generally controls the scenarios under which the axons are in tension (T) or compression (C). Black dashed circles and gray ones highlight the typical convex convolution patterns when axons are in compression and tension, respectively. For these experiments the stiffness of the axons is considered to be the same as that of the core.