I can confirm from personal experience. The lack of oxygen has some part to play in this phenomenon.
As an ex-para with thousands of jumps logged, both military and civil, I've had a wide variety of close to death experiences inc:
Hang-up: This is when the "static-line", which is supposed to pull open your canopy, does not. You're left hanging under the aircraft untill cut free by the jump-master (or yourself), then to open the reserve canopy.(from 800ft)
Double mal: (after free-fall) First canopy mal-function followed by cut-away (releasing this first canopy) followed by reserve canopy mal-function (partial) followed by extreme landing (broken feet, legs, ribs and wrists.)
Multiple canopy entanglement: During "canopy relative work" (CRW). My own plus an others canopies became entangled resulting in very high descent rate, plus uncontrollable spin followed by more broken legs, ribs etc.
Throughout these, and many other "minor" incidents, I remained conscious and lucid, working for a 'fix" untill impact.
I had one near drowning incident, a capsize in freezing waves, unable to "roll" or get out due to overloading with equipment. I was rescued unconscious, and revived by squad mates.
This did give me the "life passing before the eyes" experience, one which I would not like to suffer again!