The K-complex: its slow (<1-Hz) rhythmicity and relation to delta waves.
The K-complex is a major graphoelement of sleep EEG. This report demonstrates that K-complexes emerge from a cortically generated slow (<1-Hz) oscillation. Human EEG as well as cat cellular and field potential recordings converge into demonstrating that the K-complex results from a synchronized cortical network that imposes periodic excitatory and inhibitory actions on cortical neurons. We additionally show the correspondence between neuronal activities and the shape of the K-complex. Spectral analysis confirms the periodic recurrence of human K-complexes, with main peaks at 0.5 to 0.7 Hz. It is also shown that the spectral content in the delta band (1 to 4 Hz) is partially due to the shape and duration of the K-complex.
Amzica
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Laboratoire de Neurophysiologie, Faculté de Médecine, Université Laval, Quebec, PQ, Canada.
Steriade
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D000200:Action Potentials; D000778:Anesthetics, Dissociative / Q000494:pharmacology; D000818:Animals; D002415:Cats; D003700:Delta Rhythm; D004569:Electroencephalography; D004594:Electrophysiology; D006801:Humans; D007649:Ketamine / Q000494:pharmacology; D010507:Periodicity; D011930:Reaction Time; D012890:Sleep / Q000502:physiology*; D014991:Xylazine / Q000494:pharmacology
D000778:Anesthetics, Dissociative; D014991:Xylazine; D007649:Ketamine