If it’s not clear, I simply mean without resting their heads on anything. I’m having an argument about this. I say no.
I would venture to say yes. I know that I have fallen asleep at work with my right hand on my mouse and my left hand on ctrl+c just sitting there like I am working. Don’t tell my boss.
Hell, you can sleep while walking. Soldiers often talk of falling asleep while marching. Example:
I’ve fallen asleep that way countless times… but generally my head falls forward at some point (usually because I fall asleep that way in cars).
It’s terrible sleep, but it’s there. I’ve even remembered dreaming.
I’m doing it right now. 
I wake up every morning… oh wait…
In my experience, you can fall asleep sitting up with your head erect, but not with any regularity. I slept that way during my bus commutes to and from school for many years.
Also in my experience, the lighter the sleep, the greater the chance of staying upright.
Aleksandr Solzhenitsyn writes in The Gulag Archipelago about a prisoner that learned to sleep sitting up, head up, on a stool in his cell sufficient to fool the guards into believing he was still awake. (Sleep deprivation was part of the “interrogation techniques” used to extract confessions from prisoners of SMERSH and the Gulag system.) This is clearly an exceptional case, though, and it’s unclear what stage of sleep he attained. Generally speaking, a full relaxation (voluntary or involuntary) of the muscles results in the head falling forward or to one side (hence, the inability of infants and sufferers of neuromuscular diseases to effect a head-up posture).
This seems to be pretty common in land mammals–even unglates that sleep in an erect body posture typically bow their heads when at rest)–but other erect stance animals (turkeys, for instance) sleep with heads erect. I’d say that it’s one of the many penalties for these gignormous brains we haul around.
Stranger
Certainly. I used to do this all the time in church. If you’re going to do it deliberately rather than, say accidentally falling asleep in class, you can deliberately adopt a balanced posture so that when you fall asleep your head doesn’t flop and wake you up.
I worked several double shifts and went to sleep on my feet. Therefore I know it is possible. Your are on auto pilot till something gives and you awake with a start. I took some citrated caffeine and when it kicked in I was WIDE AWAKE !
You should see most of the seated commuters in trains during a Tokyo morning rush. They, or shall I say “WE”, usually sleep sitting upright. However, for some, the head eventually tilts to one side.
Yep, I’ve done it.
The daughters of George III and Queen Charlotte used to have to stand behind their mother’s chair at royal receptions for hours at a time. Court etiquette prohibited the princesses from sitting. It’s said they learned to sleep while standing: The Royal Scribe
When I was in high school I used to constantly fall asleep with my head erect. The subsequent tilting of the head was usually enough to make me awake with a falling sensation.
My father falls asleep driving, none of the ‘buzz you to wake you up’ devices work 'cause his head doesn’t fall backwards. We used to have to take turns in thefront seat talking to him to keep him interested and elbow him when he fell asleep. It was hard to do, his head didn’t move at all, you really had/have to watch his eyes.
I can’t personally fall asleep with my head up, no matter how much I wish I could, but I did fall asleep marching w/ ~30lbs. once. I fell asleep as my left foot went forward in the stride and I awoke when it struck the ground, I wobbled, but didn’t eat pavement…
Yeah, he’s really good at that head-erect thing. In the first few seconds his head doesn’t really move at all.
“Is he drifting toward the line because you just drift when you drive, or because he’s asleep? No, he corrected it. Wait, this time I think he’s going to touch the line!” [taps shoulder, wakes driver.]
Flop houses used to have ropes
- the punters would sleep standing up, although I doubt that their heads were erect.