Abnormal cortical excitability in Rett syndrome.
Visual and somatosensory evoked potentials (VEPs and SEPs) were studied in 9 patients with Rett syndrome and compared with those in 6 patients with photosensitive progressive myoclonus epilepsy (PPME). In Rett syndrome, a giant III-IV amplitude of VEPs was present in 8 patients, although none exhibited giant II-III amplitudes. Four of 6 patients with Rett syndrome who demonstrated giant SEPs did not have a C reflex. Conversely, the patients with PPME demonstrated giant II-III and III-IV amplitudes in VEPs, and giant SEPs with concurrent positive C reflexes. It is concluded that the mechanism of altered cortical excitability in Rett syndrome is different from that in PPME.
Yamanouchi
H
H
Department of Pediatrics, School of Medicine, Gunma University, Japan.
Kaga
M
M
Arima
M
M
D000293:Adolescent; D001143:Arousal / Q000502:physiology*; D002540:Cerebral Cortex / Q000503:physiopathology*; D002648:Child; D002675:Child, Preschool; D004569:Electroencephalography; D017029:Epilepsy, Complex Partial / Q000175:diagnosis / Q000503:physiopathology; D004830:Epilepsy, Tonic-Clonic / Q000175:diagnosis / Q000503:physiopathology; D005073:Evoked Potentials, Somatosensory / Q000502:physiology; D005074:Evoked Potentials, Visual / Q000502:physiology; D005260:Female; D006801:Humans; D011930:Reaction Time / Q000502:physiology; D015518:Rett Syndrome / Q000175:diagnosis / Q000503:physiopathology*