SHANK2 and attention deficit-hyperactivity disorder: These results show that the hyperactivity of Shank2-/- adult mice is not attenuated by methylphenidate, and therefore might not be related to “ADHD-like hyperactivity.” Our results are consistent with those from Pappas et al. (2017) who also observed an increased hyperactivity in Shank2Δex24 mutant mice treated with amphetamine (2 mg/kg), while this hyperactivity was rescued by the mood stabilizers valproic acid or lithium (Pappas et al., 2017).