Do you think this is realistic? Do you think there are times where it is okay and times it is not. I was going to write a scene using it when I thought about it. Obviously if you are being loud you could wake someone up but is there a line where it becomes unnatural? I did a google search but I got results for sleep deprivation.
A quick search suggests it is possible to train yourself to sleep with your eyes open, but it is bad for your eyes. Some people apparently also do this involuntarily. I think this would ordinarily imply you are a light (or poor?) sleeper, and in that sense, you'd be more aware of someone sneaking up on you while you slept... but not that you could literally see and react while sleeping. Also fwiw I would buy a light sleeper who slept with an open eye in a story, but not that they literally saw while they slept in a realistic story. Fwiw, some birds can apparently do this... Keep one eye open and use half of their brain to observe threats while they're asleep, or something like that. Something to keep in mind for those writing a monster girl story, I guess!
I guess it wouldn't be unreasonable for a character to be trained to stay in a light sleep but it would only be useful if they were in danger as getting a full nights rest is pretty important. I know personally it is possible if you set short alarms as I have felt like I had more dreams that way. Mainly did it to put off getting up. I am in a fantasy setting so I could create some magical ability that would cover it.
Yeah, I think if it's just light sleep you want, nobody would bat an eye that a warrior could train for it. Especially if it's a rugged warrior who cares more about staying alive sleeping anywhere than getting their doctor recommended beauty sleep. Taking it a bit farther, it would probably make sense to assume the warrior trained in this couldn't turn it off/on at will, if it's trained... So maybe make sure it's the type of person who would willingly submit themselves to that light-sleeping lifestyle. Sounds like it is, though.
That poor Cyclops girl... Depending on the situation, I could imagine that you don't need to wake up. - Being part of a group - Sleeping under a pile of leaves (you shouldn't be a heavy snorer I guess) - Sleeping on a tree - Set up traps (e.g. alarm traps)
Its possible to cut the corpus callossum - the cord that connects the left & right hemisphere in the brain (This is sometimes done in life or death situations with severe epilepsy). The result of this is that both halves of the brain function relatively independently - and each controls one eye! If you then say read a newspaper with one eye closed, you cannot then open it and close the other one and write down what you had read. - the other half of the brain doesnt know. So.... it would be possible (at least in relatively unscrutinized fiction) for one eye to be open and (at least half the brain) alert, while the other eye is closed and half the brain sleeps.
Well I didn’t literally mean with an eye open although the thought is amusing. I more was going for the idea that they would instantly react to danger. The character is sleeping and about to be killed when suddenly they wake up and are suddenly moving to stop the killer.
No one really sleeps with eyes opens, unless for a medical condition. Trained warriors may have a lighter sleep, some kind of awareness, like cavemen who slept in caverns, that is not exactly just like being awake. If the enemy is stealthy enough it may easily approach unnoticed. Think about it like sneaking past a sleeping guard dog. Does it sleeps with its eyes open? no. Will it probably notice you? yeah.
Aah, it's fine. A bit of cheese never hurt anyone. If it makes a cool character cooler, I saygo for it!
https://www.helpguide.org/harvard/biology-of-sleep-circadian-rhythms-sleep-stages.htm ↑ That website suggests a sensitivy to light at certain stages of the sleep cycle. Might make it plausible if your warrior is woken by the glint of a knife moments before their assassin has a chance to strike.
