NRG1 and schizophrenia: We used cocaine because rates of cocaine use in schizophrenia patients are more than 5 × higher than the general population (Sara et al. 2014; Volkow 2009), and while Nrg1 TM HET mice show increased susceptibility to the locomotor stimulating effects of the psychostimulant methamphetamine (Spencer et al. 2012), the response of these mice to cocaine is completely unknown.