title: Scalp-recorded high-frequency oscillations in childhood  sleep-induced electrical status epilepticus.
abstract: Because high-frequency oscillations (HFOs) may affect normal brain functions, we examined them using electroencephalography (EEG) in epilepsy with continuous spike-waves during slow-wave sleep (CSWS), a condition that can cause neuropsychological regression. In 10 children between 6 and 9 years of age with epilepsy with CSWS or related disorders, we investigated HFOs in scalp EEG spikes during slow-wave sleep through temporal expansion of the EEG traces with a low-cut frequency filter at 70 Hz as well as through time-frequency power spectral analysis. HFOs (ripples) concurrent with spikes were detected in the temporally expanded traces, and the frequency of the high-frequency peak with the greatest power in each patient's spectra ranged from 97.7 to 140.6 Hz. This is the first report on the detection of HFOs from scalp EEG recordings in epileptic patients. We speculate that epileptic HFOs may interfere with higher brain functions in epilepsy with CSWS.
authors.affiliation: Department of Child Neurology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences and Okayama University Hospital, Kita-ku, Okayama, Japan. k_koba@md.okayama-u.ac.jp
authors.forename: Katsuhiro
authors.initials: K
authors.lastname: Kobayashi
authors.forename: Yoshiaki
authors.initials: Y
authors.lastname: Watanabe
authors.forename: Takushi
authors.initials: T
authors.lastname: Inoue
authors.forename: Makio
authors.initials: M
authors.lastname: Oka
authors.forename: Harumi
authors.initials: H
authors.lastname: Yoshinaga
authors.forename: Yoko
authors.initials: Y
authors.lastname: Ohtsuka
mesh_terms: D001921:Brain / Q000503:physiopathology*; D002540:Cerebral Cortex / Q000503:physiopathology; D002648:Child; D004569:Electroencephalography / Q000379:methods / Q000706:statistics & numerical data*; D005260:Female; D005583:Fourier Analysis; D006801:Humans; D018887:Landau-Kleffner Syndrome / Q000175:diagnosis / Q000503:physiopathology; D008297:Male; D009991:Oscillometry / Q000706:statistics & numerical data; D012890:Sleep / Q000502:physiology*; D013226:Status Epilepticus / Q000175:diagnosis / Q000503:physiopathology*