COMPARISON OF AN AUTOMATIC SLEEP ANALYZER TO VISUAL ANALYSIS OF THE ELECTROENCEPHALOGRAM.

Abstract : The report describes the evaluation of a prototype automatic sleep analyzer. Eight thousand minutes of visually scored sleep electroencephalogram (EEG) recorded from nine normal subjects were played back for scoring by an instrument designed to automatically estimate depth of sleep from the EEG. The linear correlation coefficients between the visual and machine scores were 0.67 for Lead O3 - F1 and 0.60 for Lead T5 - OzPz. Forty-eight percent of the scores were in agreement by stage; ninety-five percent agreed within one stage. The analyzer described was a small, easily operated device with an output suitable for graphical display of sleep stages. The instrument operates essentially in real time and accepts EEG directly from one scalp lead. User needs dictate the choice between visual or automatic EEG classification techniques. (Author)