Hoxb8 mutants exhibit increased cortical synapse and spine density within the frontal cortex along with increased dendritic spines in the dorso- and ventro-medial subregions of the striatum, suggesting that increases in excitatory corticostriatal synapses may be implicated in the elevated injurious self-grooming, anxiety, and social deficits in Hoxb8-/- animals [118]. Here, HOXB8 is linked to Anxiety.