Artifacts present on this recording include the ECG artifact in the electro-oculogram and ECG leads.
The MSLTs followed standard methods for collection of EEG, electro-oculogram, and chin electromyogram data.
The clinical electro-oculogram (EOG) measures the amplitude of the standing potential and light response.
The bilateral electro-oculogram, eight channels of EEG, chin and anterior tibial EMG, and analog output from a body position sensor were also monitored.
Most importantly, eye movements are recorded using an electro-oculogram to distinguish the sleep onset period from the waking state and also to detect Rapid Eye Movement sleep.