title: On-off intermittency of thalamo-cortical oscillations in the electroencephalogram of rats with genetic predisposition to absence epilepsy.
abstract: Spike-wave discharges (SWD) are electroencephalographic hallmarks of absence epilepsy. SWD are known to originate from thalamo-cortical neuronal network that normally produces sleep spindle oscillations. Although sleep spindles and SWD are considered as thalamo-cortical oscillations, functional relationship between them is not obvious. The present study describes temporal dynamics of SWD and sleep spindles as determined in 24h EEG recorded in WAG/Rij rat model of absence epilepsy. SWD, sleep spindles (10-15 Hz) and 5-9 Hz oscillations were automatically detected in EEG using wavelet-based algorithm. It was found that non-linear dynamics of SWD fitted well to the law of 'on-off intermittency'. Sleep spindles also demonstrated 'on-off intermittency', in contrast to 5-9 Hz oscillations, whose dynamics could not be classified as having any known type of non-linear behavior. Intermittency in sleep spindles and SWD implies that (1) temporal dynamics of these oscillations are deterministic in nature, and (2) it might be controlled by a system-level mechanism responsible for circadian modulation of neuronal network activity.
authors.affiliation: Institute of the Higher Nervous Activity and Neurophysiology of Russian Academy of Sciences, Butlerova str., 5A, Moscow, 117485, Russia. eu.sitnikova@gmail.com
authors.forename: Evgenia
authors.initials: E
authors.lastname: Sitnikova
authors.forename: Alexander E
authors.initials: AE
authors.lastname: Hramov
authors.forename: Vadim V
authors.initials: VV
authors.lastname: Grubov
authors.forename: Alexey A
authors.initials: AA
authors.lastname: Ovchinnkov
authors.forename: Alexey A
authors.initials: AA
authors.lastname: Koronovsky
mesh_terms: D000818:Animals; D004569:Electroencephalography; D004832:Epilepsy, Absence / Q000235:genetics* / Q000503:physiopathology*; D008297:Male; D009415:Nerve Net; D051381:Rats; D012890:Sleep / Q000502:physiology*; D013788:Thalamus / Q000502:physiology