The second endophenotype of interest, decreased inhibitory control, includes impulsivity and other externalizing characteristics that contribute to acting without appropriate forethought (Depue and Collins, 1999; Dick et al., 2013; Kaiser et al., 2016; Wardell et al., 2015). Like low LR, aspects of diminished inhibitory control relate to both genes and environment, can differ across sexes, and are likely to change with age and stage of development (Dick et al., 2013; Meyers et al., 2014; Ohannessian and Hesselbrock, 2008).
