A continuous evaluation of the awake sleep state using fuzzy reasoning

Sleep staging is one of the most important tasks on the context of sleep studies. From more than 40 years the gold standard to the characterization of patient´s sleep is the use of the rules proposed by Rechtschaffen and Kales (R&K). However this method has the limitation of the unnatural assignment of discrete stages instead of doing it in a continuous manner. As part of a more general framework, this paper reports an automatic method for the characterization of the R&K´s awake sleep stage through the use of fuzzy reasoning. A continuous evolution of the wakefulness state of the patient during the night is provided as output.