Fig. 7. Schematic drawing of nVII motor-neuron migration in the wild-type and olt embryos. In the wild-type embryos, the nVII motor neurons (green) migrated caudally near the pial surface of the hindbrain. By contrast, in the olt embryos, because the neuroepithelial cells (red) had lost their ability to prevent integration of the nVII motor neurons, the motor neurons migrated towards the ventricle by extending aberrant processes radially to the ventricle. Directions of migration of the nVII motor neurons are indicated by arrows. See text for details.