Given the apparent link between impaired MeCP2 function and altered behavioral state rhythmicity in Rett syndrome patients [14] and in Mecp2308/y mice [15], we sought to determine whether impaired MeCP2 function would be sufficient to alter the daily EEG behavior, thermoregulatory, and/or periodic ambulatory cycles of mice. Here, MECP2 is linked to atypical Rett syndrome.