Micro- and macrostructure of sleep EEG

EEG provides an important and unique information about the sleeping brain. The standard interpretation of polysomnographic recordings describes their macrostructure in terms of sleep stages, delineated according to the criteria summarized by Rechtschaffen and Kales. This description of sleep macrostructure relies on division of the time axis into fixed time epochs (20 or 30 seconds) - this naturally implies some limitations. Therefore, several descriptors of sleep microstructure have been proposed. They rely e.g. on quantification of sleep spindles and slow wave activities, detection of arousals, etc. This study proposes a solution in terms of a framework based upon adaptive time-frequency approximations—a recent, advanced method of signal processing. Proposed approach provides compatibility with the visual EEG analysis and standard definitions of EEG structures, and describes both the macro- and microstructure of sleep EEG.

Micro- and macrostructure of sleep EEG. Urszula Malinowska, Piotr J. Durka, Katarzyna J. Blinowska, Waldemar Szelenberger, Andrzej Wakarow. IEEE Engineering in Medicine and Biology Magazine, 2005.