Prospective longitudinal overnight video-EEG evaluation in Phelan-McDermid Syndrome

This is the first and most abundant prolonged awake and sleep video-EEG data recorded in a PMS cohort to date. The importance of overnight prolonged EEGs is highlighted by findings from this study, as they can be used to document the varied topographies of EEG abnormalities in conditions such as PMS, which are often missed during routine EEG studies. While the long-term significance of the EEG abnormalities found (beyond 1 year) remains uncertain despite their persistence over time, these findings do underscore the current clinical recommendation that overnight prolonged EEG studies (with sleep) should be conducted in individuals with PMS.