To understand the function of FOXP1 in specific brain regions, in this paper, the authors used a mouse model where Foxp1 is removed from the neocortex, the outermost layer of the brain, and the hippocampus, a brain region important for memory. The authors then studied these mice in adulthood and found that the mice had simpler, less complex communications. The authors also report that these mutant mice have reduced social interactions, hyperactivity, and anxiety-like behaviors. Though the mice had no change in general learning ability, they had difficulties in spatial learning, or remembering the location of where objects are or where an event occurred. The volume of the hippocampus was also decreased. Finally, the authors measured how loss of Foxp1 affects overall gene expression and found that many genes important for brain development are altered as well as genes already implicated in ASD. Different genes were regulated by Foxp1 in either the hippocampus or neocortex. Together, these data suggest that Foxp1 has specific functions in different regions of the brain.