SYNGAP1 and epilepsy: Abnormalities in synaptic connectivity may underlie the cognitive pathologies and epilepsy in SYNGAP haploinsufficiency.28,29 Network activity pathophysiology in NDDs may be detected by analysing connectivity between EEG electrodes.30 We therefore analysed the imaginary coherence, a generalization of correlation in the phase domain,24 between voltage signals in our multi-site recordings during each brain state.