Auditory evoked potentials compared to performance measures and EEG in assessing excessive daytime sleepiness in narcolepsy-cataplexy.

The AEP to the repetitive stimuli of the Wilkinson auditory vigilance task was compared between untreated patients with narcolepsy-cataplexy and matched controls for periods during which the tones were preceded by 13 sec or more of wakefulness (defined by EEG-polygraphic criteria). During these periods it had been found previously that narcoleptics did not perform worse than did controls. The AEP, nevertheless, showed significant differences for narcoleptics. These were similar to changes described for drowsiness in normals. The AEP, therefore, showed changes related to excessive day time drowsines in narcolepsy-cataplexy when a sensitive performane measure and visual analysis of EEG-polygraphic recordings did not.