Slow-wave activity (SWA)

Power spectral analysis is a more modern tool to assess the slow waves in the sleep EEG. Consecutive epochs are analyzed for their frequency contents.

Slow-wave activity can be visualized by plotting the consecutive power values over time for the lowest frequencies only.


hours after lights off

The correspondence between slow-wave activity and deep sleep (stages 3+4) is obvious.

Power spectral analysis

 

 

 

©1998 BITS OF SLEEP (Demo) : Variations of sleep: Sleep stages and sleep intensity.