SYNGAP1 and sleep disorder: As sleep disorders are present in more than 60% of the SYNGAP1 population (Vlaskamp et al., 2019), we also examined sleep architecture by analyzing sleep spindles, an EEG signature that reflects the strength and malleability of thalamocortical circuits (Schönauer and Pöhlchen, 2018; Fernandez and Lüthi, 2020).