This study aims to elucidate the pathogenic mechanisms of neurodevelopmental disorders (NDDs), including autism spectrum disorder (ASD), from two perspectives: (1) epigenomic alterations and (2) changes in large-scale brain activity transition dynamics. In particular, we will address this issue using mouse models that exhibit ASD-like symptoms induced by juvenile social isolation stress (environmental factor) as well as mouse models carrying high-risk genetic mutations for ASD/NDD (genetic factor).