TACR1 and attention deficit-hyperactivity disorder: We have reported previously that the hyperactivity of NK1R−/− mice is attenuated by the psychostimulants, d-amphetamine and methylphenidate, as in ADHD (Yan et al., 2009; 2010), but d-amphetamine did not prevent impulsivity or inattentiveness in the 5-CSRTT (Yan et al., 2011).