Patent ID: 7623912
Filing Date: 2009-11-24
Classification: A61B

Abstract:
1. A method of determining a Slow-Wave-Sleep (SWS) period and a Non-SWS (NSWS) period from signals of electrical activity recorded of a chest of a sleeping subject, the signals being measured over a plurality of epochs, the method comprising: extracting a series of cardiac R-R intervals from the signals and obtaining a time-frequency decomposition from said series of cardiac R-R intervals; and using said time-frequency decomposition to determine a SWS period defined over a plurality of SWS epochs, thereby also determining NSWS period defined by all epochs other than said SWS epochs, said NSWS period encompassing at least one Rapid-Eye-Movement (REM) sleep period and at least one Non-REM (NREM) sleep period; thereby determining the SWS period and the NSWS period of the sleeping subject.