From the moment a persons heart stops beating, stop functioning, how long does it take until the brain starts to shut down and how long until it's completely non functional and you're dead beyond the point of revival? It's probably hard to conduct such an experiement but have there ever been any tests done that compares a persons brain activity who is sleeping to that of someone who's heart has just stopped beating and if they're not revived they'll die? One last question for anyone who's a doctor or surgeon, when you've revived someone, what do they tell you later afterwards, once they've recovered. Is there anything that's patients tend to recall happening? I assume it would just be like being knockout?