Clete A. Kushida, MD, PhD, Neurologist and Division Chief and Medical Director of Stanford Sleep Medicine Center, explains how sleep is measured in clinical trials such as the REST-ON study, a double-blind, randomized, placebo-controlled phase 3 trial assessing the efficacy and safety of FT218 (once-nightly sodium oxylate) in the treatment of excessive daytime sleepiness and cataplexy in narcolepsy patients.

Narcolepsy is a rare neurological disorder characterized by excessive sleepiness during the day, often with periods of brief involuntary sleep and/or cataplexy.

As Dr. Kushida explains, the three main measures of sleep are the electroencephalogram (EEG), electrooculogram (EOG), and the electromyogram (EMG). When a person is awake, the brain wave activity is typically between 8 and 13 Hz (alpha waves). During N1 sleep – the first stage of sleep – alpha waves become theta waves (4-8 Hz). During this time, chin muscle and eye movement activity also decreases. As N1 sleep indicates a person falling asleep, these indicators of N1 are often used in sleep studies like the REST-ON when measuring, for instance, how quickly one falls asleep.

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