BLOC1S4 and schizophrenia: Given prior evidence that a dysregulation of cortical excitation/inhibition balance during postnatal life contributes to the establishment of endophenotypes linked to schizophrenia (Rosen et al., 2015), we next sought to examine whether chronic CNO-mediated hM3Dq DREADD activation of CamKIIα-positive forebrain excitatory neurons in the early postnatal window influenced sensorimotor gating behavior in adulthood (Figure 4A).