Our results identify a novel and non-redundant role for Akt3 in prefrontal cortical and hippocampal-mediated cognitive function, identify potential neurobiological mechanisms underlying association of the AKT3 gene with schizophrenia relevant to cortical development, and identify Akt3 as a critical determinant of AKT signaling in the brain. This evidence concerns the gene AKT3 and schizophrenia.