I am an engineer working on PSG studies datasets.
The particular dataset that I'm looking at has recorded 2 EEG channels, eye movement (HEOG), chin EMG, body temp and respiration and an event marker!
One thing that I don't quite understand is what the term "Event Marker" refers to? since you have the scored hypnogram, what does this event marker point out to?
This makes sense in Holter monitors since it points out to epochs through which palpitations are sensed by the patient.