title: [Influence of the brain functional state evoked by spreading depression wave propagation on the recurrent waves properties].
abstract: EEG aftereffects of spreading depression waves were studied in waking rabbits in chronic experiments by spectral coherence analysis. Experiments were divided in two groups: early (from the first to the third-fourth experiments) and late (fifth-tenth experiments). During the early experimental series, unilateral persistent EEG changes consisting in an increase in the delta- and beta-band power with a simultaneous depression of the gamma-band activity were observed in the ipsilateral to SD hemisphere. In addition, interhemispheric coherence between symmetrical cortical points decreased. During the late experimental series, a generalized bilateral increase in the power of the delta and beta activity was demonstrated with a rise in coherence in the beta band. This generalized activity occurred cyclically and was distinct during a long period of time (2-3 hours) after propagation of a single SD wave. Such kind of cyclical activity blocked the propagation of subsequent SD waves in the neocortex of a waking rabbit and decreased the probability of recurrent wave origin up to a complete cessation of wave generation. Thus, a cortical SD wave provoked the appearance of synchronized beta oscillations in the EEG, which in turn actively influenced the properties of recurrent waves.
authors.forename: G Ia
authors.initials: GIa
authors.lastname: Roshchina
authors.forename: V I
authors.initials: VI
authors.lastname: Koroleva
authors.forename: V I
authors.initials: VI
authors.lastname: Davydov
mesh_terms: D000818:Animals; D001921:Brain / Q000502:physiology*; D058256:Brain Waves; D013181:Cortical Spreading Depression; D019579:Neocortex / Q000502:physiology; D011817:Rabbits