Radial glial cells

Also referred to as the Bergmann fibers of the Golgi epithelium cells, they are a special class of astrocytes that extend from the ventricles to the cortex and along which migrating neurons travel to their final destinations.  With the completion of migration, the radial glia fibers break apart and the cells are transformed into fibrous astrocytes.  Some neurons do not follow radial paths.  The transformation of radial glia into astrocytes is an example of a qualitative regression (or ontogenetic adaptation). 

See Astrocyte, Cell migration (cerebral cortex), Cerebellum (development), Glial cells, Neuronal migration disorders, Ontogenetic adaptation, Proliferative ventricular zone, Quantitative and qualitative regressions, Ventricle