Rett's syndrome: a neurophysiological study.

Thirteen girls with Rett's syndrome were evaluated with wakefulness and sleep polygraphic records and EMG studies. The main EEG findings were paroxysmal activity during sleep, multifocal in younger and unifocal in older girls, and "pseudorhythmic flattening". In the opinion of the authors, the changes with age are related to evolution of the disease or maturational changes of CNS. The affectation of the peripheral nervous system was demonstrated in almost half the patients.