SYNGAP1 and Generalized non-motor (absence) seizure: We previously reported that Syngap+/Δ−GAP rats displayed absence seizures more frequently than littermate controls, utilizing 6 h EEG (Fig. 1A, Supplementary Figure 1) recordings, when animals were in a quiet wake state.17 To determine whether Syngap+/Δ−GAP animals have abnormalities in their brain state distribution, we classified all individual 5 s recording epochs from those previous recordings as NREM sleep, REM sleep or wake (Fig. 1A).