Considerations and procedures for acquiring EEG as part of multi-site studies for Rett syndrome and other genetic neurodevelopmental disorders.

There is increasing interest in the utility of electrophysiological measures such as resting EEG and evoked potential (EPs) to serve as biomarkers to facilitate therapeutic development for rare genetic neurodevelopmental disorders (NDDs). Research on this topic thus far has been encouraging, but has also revealed the necessity for unique methods when acquiring EEG and EPs in children with genetic NDDs. Details of these methods are typically beyond the scope of research publications, yet are crucial to the quality and ultimately, usability of the data. In the current manuscript, we detail the methods that we have developed for acquiring EEG and EPs as part of multi-site studies with participants with Rett syndrome, CDKL5 deficiency disorder, MECP2 duplication syndrome, and FOXG1 syndrome. By making our methods accessible, we hope to support other groups interested in acquiring EEG and/or EPs as part of clinical trials or research studies with individuals with genetic NDDs, including groups without prior experience with EEG/EP acquisition. The paper is presented as step-by-step procedures followed by a discussion of issues that may arise during acquisition and ways to troubleshoot these issues. We then discuss considerations for choosing EEG equipment and study paradigms and briefly, considerations for data analysis.