When the heartbeat stops

[Meatpie]

Most people think that when your heart stops beating that's it - you are dead.

But autopsy a dead dude and your entire worldview will be shattered forever.

Death is entirely in the brain, biologically it happens in stages but from the perspective of the dead person it's all over in a split second, the moment you lose your consciousness. Sadly you can never know when you are truly dead.

When your heart stops beating consciousness is not lost immediately but 15-20 seconds later. Up to this point, a person may not even feel like dying.

Most tissues and organs of the body can survive clinical death for considerable periods. Blood circulation can be stopped in the entire body below the heart for at least 30 minutes, with injury to the spinal cord being a limiting factor.[SUP][/SUP] Detached limbs may be successfully reattached after 6 hours of no blood circulation at warm temperatures. Bone, tendon, and skin can survive as long as 8 to 12 hours.


The brain, however, appears to accumulate ischemic injury faster than any other organ. Without special treatment after circulation is restarted, full recovery of the brain after more than 3 minutes of clinical death at normal body temperature is rare.

Neuronal necrosis sets in within minutes. That's why dead guys are so beautiful, the brain switches off like a computer but the rest of the body can remain fuckable for hours after death.

Even more amazing is that different regions of the brain die at different times. The most vulnerable cells in the brain, CA1 neurons of the hippocampus, are fatally injured by as little as 10 minutes without oxygen.

Amazingly, reducing body temperature can double the time neurons can survive without oxygen. This is still an area of research, no one knows how exactly this works there are several theories.

 

[keyman419]

I totally understand all of this. I tend to think that the "white light" that some people experience is in fact the brain dying and shutting down. It would be an interesting experience for sure. There is no instant death. Even in a trauma situation, there is still a dying process as the brain is starved and ends.

 

[Meatpie]

There is no instant death. Even in a trauma situation, there is still a dying process as the brain is starved and ends.

Depends on how you look at it.

As I said from the point of view of the dying person their moment of death is the moment they lose consciousness. This happens in a split second, neurons switch off in less than a second.

It's like when you fall asleep and you try to catch the exact moment you slip - YOU CAN'T because there is no moment after to realize it.

 

[PiercedChest]

Fascinating thread!

As I said from the point of view of the dying person their moment of death is the moment they lose consciousness. This happens in a split second, neurons switch off in less than a second.

Yes, individual neurons do. I expect different brain circuits and functions to collapse at slightly different times though, because so many neurons are involved, they don't all switch off at the same split second and some circuits will be more robust that others. It is frequently reported that sight vanishes soon, and hearing late (last). I've experienced this myself when I fainted once: I started to feel dizzy and weak, sat down, on a small stool, then everything went black, but I could still hear, then the sound went darker and fainter. When I came to, I was lying on the floor, and I didn't remember falling. No tunnels with light or out-of-body-experiences unfortunately.

It's like when you fall asleep and you try to catch the exact moment you slip - YOU CAN'T because there is no moment after to realize it.

Yeah, I've tried that so many times when I was young, and always failed. The reason you can't (as I see it) is because we don't have a soul, or spirit, that lives in our heads (at least not as a seperate entity, a spirit is nothing but a brain that is working), but we do have a functioning brain, and if the brain changes it's function (falling asleep), then obviously you can't also have a brain at the same time that isn't falling asleep and is 'watching' the same process. To me this is actual proof of the nonexistence of spirits apart from brains in action.

 

[Meatpie]

It is frequently reported that sight vanishes soon, and hearing late (last).

I've heard this from friends who had relatives die in their arms, hearing is the last to go.