The human K-complex represents an isolated cortical down-state.

Full Abstract

The electroencephalogram (EEG) is a mainstay of clinical neurology and is tightly correlated with brain function, but the specific currents generating human EEG elements remain poorly specified because of a lack of microphysiological recordings. The largest event in healthy human EEGs is the K-complex (KC), which occurs in slow-wave sleep. Here, we show that KCs are generated in widespread cortical areas by outward dendritic currents in the middle and upper cortical layers, accompanied by decreased broadband EEG power and decreased neuronal firing, which demonstrate a steep decline in network activity. Thus, KCs are isolated "down-states," a fundamental cortico-thalamic processing mode already characterized in animals. This correspondence is compatible with proposed contributions of the KC to sleep preservation and memory consolidation.

Author information

Author/s: Cash, Sydney S (SS); Halgren, Eric (E); Dehghani, Nima (N); Rossetti, Andrea O (AO); Thesen, Thomas (T); Wang, Chunmao (C); Devinsky, Orrin (O); Kuzniecky, Ruben (R); Doyle, Werner (W); Madsen, Joseph R (JR); Bromfield, Edward (E); Eross, Loránd (L); Halász, Péter (P); Karmos, George (G); Csercsa, Richárd (R); Wittner, Lucia (L); Ulbert, István (I);

Affiliation: Department of Neurology, Epilepsy Division, Massachusetts General Hospital, Harvard Medical School, Boston, MA 02114, USA. scash(-atsign-)partners.org

Grants: NS18741 (Agency:NINDS NIH HHS) ; NS44623 (Agency:NINDS NIH HHS)

Journal and publication information

Publication Type: Journal Article; Research Support, N.I.H., Extramural; Research Support, Non-U.S. Gov't

Journal: Science (New York, N.Y.) (Science), published in United States. (Language: eng)

Reference: 2009-May; vol 324 (issue 5930) : pp 1084-7

Dates: Created 2009/05/22; Completed 2009/06/04;

PMID: 19461004, status: MEDLINE (last retrieval date: 6/4/2009, IMS Date: 04 Jun 2009 00:00:00)

Sourced from the National Library of Medicine. Abstract text and other information may be subject to copyright.

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