I have mixed feelings about this. I'm someone who sleeps on average 6 hours/night. When I have experiments, then I sometimes drop down to 4 hrs/night. I've f

I have mixed feelings about this. I'm someone who sleeps on average 6 hours/night. When I have experiments, then I sometimes drop down to 4 hrs/night. I've found that I can manage with 4 hrs/night for about a week (it has gotten a bit harder with age)--BUT I know that I'm not as effective or creative when dealing with such little amounts of sleep. I also know that I'm more prone to make errors and try to develop habits so that I do the "right thing (TM)" when I'm too tired to think (it's like martial arts where you train reflexes...). I also try to know when to throw in the towel and just go home because if I stay I'm likely enough to make a mistake that will cost me more time in the end, or I need sleep so that I can think about something. However, in normal running mode, 6 hrs (as long as I'm getting exercise) feels normal to me and it's what I sleep even without an alarm unless I'm recovering from severe sleep deprivation (I don't drink coffee and generally just drink tea when I really need to stay awake...). What are other people's experiences? Somehow the dark room scenario in the article seems unrealistic. I do agree that for creative work that more sleep (in my case 6 hr/night) seems necessary--but if I find myself sleeping longer (like say 9 hrs), then I just end up feeling more tired...