Your brain doesn’t stop activity after you die either, for about 15 minutes. Even when your heart stops, that’s the main reason to why doctors can bring people back to life. Also, I’m pretty sure cells continue to circulate because of that since they don’t completely run out of oxygen yet lol. Although the reason why people are dumber or handicap if they wake up (weeks after) after the 5-15 minutes, not before that, is because their brain cells die. Whenever you see movies about god bringing people back to life after they “die,” it’s honestly just their brain not shutting off LMAO. Basically you have a chance of living even after your body shuts down for about fifteen minutes