Any thoughts on mood when waking up? Like how it affects the rest of the day in terms of how we perceive events and other people? It's always weird how we can wake up energized one day and not want to get out of bed the next even if we get equivalent hours of sleep. Do you think it might have to do with what stage of sleep we come out of?

Not many thoughts on this matter, it doesn’t intrigue me at all. I haven’t come across much on this subject, although I do know there is a ton of research on it. There are so many factors that can affect mood upon wakening, including diet, quality of sleep, alcohol, drugs, exercise, time you go to sleep, time you wake up, regular sleep patterns, medications, mental health, sleep apnea, stress, sex life, and the list goes on and on.