My first two nights were both approx 40% light sleep, 25% deep sleep, and 35% REM sleep. Last night I was 50% deep sleep, and 25% REM, 25% light sleep. (Simply put, deep sleep and REM sleep are the good ones.) Also, I only slept for 5 hours last night, as opposed to 8 and 7 the first two nights. So I got about the same amount of deep sleep and a little bit less REM sleep for the same amount of total sleep. More efficient?
In terms of drivers: I has no coffee yesterday, and a bunch of wine last night.
Interesting.
