A method for transition smoothing of sleep--waking states.

A method was developed for sequential redistribution of short-duration sleep--waking states into the long-duration behavioral state(s) that surrounds these intervals. This methodological approach is useful in determination of general sleep--waking patterns such as state durations, interstate intervals, and sleep--waking cycles. The redistribution sequences had no effect on total amount of sleep or waking categories, but did decrease stage 1 with successive redistribution steps. Examination of the slope of the curve (number of occurrences or mean epoch duration divided by successive redistributions) can be used to determine the appropriate "smoothing" for electroencephalogram (EEG) state data via location of the breakpoint in the curve. The low-pass redistribution technique has been particularly useful for smoothing large volumes of EEG state data for subsequent analyses without significantly changing the various sleep-waking states.