Radial Migration
Somal Translocation happens early during the formation of the cortex. Neurons extend themselves to the surface and then their own cell body slurps its way up itself. (like a slug lol) This is purely mechanical.
Glia-Guided Migration Is later in the formation of the cortex, where radial glia structure themselves into scaffolding that other neurons can travel on.
Tangential Migration
Neurons extending their process in the tangential direction and moving similar to Somal Translocation. This is instead guided by concentration gradients of Chemotropic Cues. This is guided by chemicals.
This shows all the migrations occuring over the cortical development.
Cortex builds inside out, the youngest cells are on the outside.
Likewise Differentiation and Synaptogenesis happens alongside Migrationneurodevelopment