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human
for anyone wondering, it's a phenomena called Hypnagogia 
it's basically an in-between of wakefulness and sleep. if you think of sleep paralysis as your mind being awake and your body is asleep, you can think of hypnagogia as your body is still awake but your mind is falling asleep
there's a really interesting book called 'Hypnagogia' that explains it more in-depth. A lot of musicians and artists from the past would utilize this as a tool, Salvador Dali is probably the most famous for it.
gpt
This. I get the loud chainsaw/buzzing noise. Most of the time it just startles my mind to being awake again then. Definitely a good opportunity to try and astral project if you get this but I’m not sure how common it is?