Polysomnograph scoring

DETAILED DESCRIPTION Briefly stated, in accordance with the invention, a method and apparatus are provided for scoring polysomnograph signals.
Known polysomnograph signals, such as EEG signals, EMG signals and EOG signals are separated into a plurality of sequential epochs.
Employing these input signals, a means and method are provided for determining whether or not there is a possibility of the existence of each of a plurality of elemental events in the signals of each of said epochs.
Such elemental events may include alpha waves, delta waves, k complex waves, spindles, etc.
The elemental events which have been determined to be possibly present may be considered to constitute candidates.
The probability of each of the occurrences of each of these candidates in each epoch is then determined.
The probabilities of occurrence of events relevant to conventional R&K sleep stage assignment (R&K events) are then determined from the probabilities of occurrence of the elemental events.
From these R&K event probabilities the likelihood of each possible stage of sleep being present is calculated (e.
g.
a probability distribution of sleep stage is calculated for each epoch).
The probability distribution of sleep stages can be modified to account for stage 2 rules, REM rules, loss factors and prior probability functions.