Fig. 10. Schematic representation of the phenotypes observed in Ebf1^-/- and Dlx1/2^-/- mutant embryos. Schematic coronal serial sections of the forebrain at the level of the occipital, parietal and frontal neocortex. In the wild-type brain, neocortical domains and thalamic nuclei that are normally interconnected have the same color and are connected by an axon tract of the same color. The axons grow through the internal capsule (open circle) and they pass through the basal ganglia (broken black lines). In Ebf1^-/- embryos, the basal ganglia domain has molecular defects (indicated by the light gray), dLGN axons (dark blue) grow ectopically into the amygdalar region; the remainder of thalamic projection show a shift in their positions in the internal capsule and in the neocortex. In Dlx1/2^-/- embryos, the basal ganglia develop abnormally (indicated by dark gray). The internal capsule is perturbed and numerous thalamic axons, the identity of which could not be clearly determined, grow into the amygdalar region and then travel rostrally (gray bundle). These probably contain dLGN axons, as these were not detected in the neocortex. Other axons grow towards the neocortex in the internal capsule; as in the Ebf1 mutants, these axons show a shift in their position within the internal capsule and in the neocortical domain that they enter.

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