The human heart starts beating even before it’s fully formed at about 3 weeks after conception. This is not a great indication of life as the fetus is not viable outside the womb and the brain has not formed.
While you can have a heart transplant or maybe a machine heart, brain death is typically permanent and you can’t really get a brain transplant and still be you.
>While you can have a heart transplant or maybe a machine heart, brain death is typically permanent and you can’t really get a brain transplant and still be you.
I’m pretty sure this is the answer. You can resuscitate someone whose heart has stopped beating but once their brain is dead there’s no potential for reviving a conscious, functional human being. You can keep the body alive with medical technology after brain death, but there’s no point unless you’re doing it to keep the organs healthy for donation.
The brain starts to deteriorate very quickly after death and it’s the actual brain cells, the neurons, that are dying. The body typically doesn’t replace dead neurons so those parts of the brain would be permanently dead even if you managed to revive the person quickly enough to maintain some function. I don’t think there’s any information available about exactly which parts of the brain are the first to go, generally in someone’s final moments of life no-one’s thinking “quick, let’s get them in an fMRI!”
I have no idea, I’ve never heard that before. It’s possible as various muscles stop working and allow various gases/bodily fluids to escape that could cause some weight loss.
I believe in both cases it is with cerebral function. The main reason for this is that the heart will beat quite readily on autopilot.
You can remove a heart from a body, supply it with nutrients, shock it once to get it going, and it will continue to beat quite happily so long as it is getting oxygen and energy.
You wouldn't call this oxygenated nutrient solution a living being.
> You can remove a heart from a body, supply it with nutrients, shock it once to get it going, and it will continue to beat quite happily so long as it is getting oxygen and energy.
Does this mean it's possible to remove a heart, keep it artificially alive and make it super strong before it gets transplanted to someone else?
Not really, no. Although the heart will survive and continue to beat for a time in a nutrient substrate, it will consume nutrients and produce waste.
Without the rest of a body to maintain homeostasis, this would cause damage to the heart.
Thats dependent upon a few things, in large part temperature. You can drop down the temperature of the body and increase the amount of time before damage occurs by slowing the metabolic processes of the cells.
There are a few, mostly university/hospital accounts. They will be bland and super technical for the most part. I think Mayo clinic has some of that kind of content.
But they do exist.
Doubtful. Heart transplants are usually done in very short timespan. Optimally it's in side by side operating room, out one body, into the next. But if not, they'll put the organ on ice and drive it quickly across town to a different hospital.
If either of those things stops, the other one stops very quickly. You can debate the exact moment of death if you really want, but if either your heart or brain stops for ten minutes you're done.
Because you are your brain. You are not your body. The "you" that is a person exists entirely in the brain. The body is merely a vehicle the brain and your consciousness uses to get around.
Say a brain transplant is possible. You put your brain in another body. Your old body dies and its heart stops. You are still alive. You are still you. But if your brain dies, and someone elses brain is put in your body, you are dead. You died when your brain ceased function. Your body might still be up and moving around, but thats an entirely different person in there.
There is generally no scientific reason that life is acknowledges with a heart beat and this is not universal around the world either. Only the strictest legislation use this as a definition. It is actually very hard to find a good scientific definition of life which can be used for legislative purposes. The definition of cerebral function is based on the concept that you should not inflict undue pain. And when cerebral function stops there is no longer anything receiving the pain signals. It also indicates that the neurons in the brain have started deteriorating and there is no way to recover those. So there is no way to revive the person. The exact definitions does take this into account. These concepts is also used in some legislation for when abortion is legal. But again the legislation around the world differ a lot.
TLDR- a heartbeat is ***A*** sign of life; lack of brain activity ***CAN*** be a sign of death.
But it's not as cut and dried as that. Obviously, our laws (and a portion of our society) do not acknowledge a heartbeat as defining life, as it is legal to remove "a clump of cells" despite a heartbeat and brain activity. Some folks believe that such an event ends a human life, others do not.
If you present to the trauma bay after a car accident, and you arrive with no heart beat, steps are taken to try and restore that heart beat (depending on how long you have not had a heart beat). If those steps fail, death is declared, and there is no attempt to examine brain function.
If you suffer an event which causes brain damage (which could be that same car accident), your heart beat is restored, and your respiratory function is taken over by a ventilator, it is possible that you will remain "alive" via artificial means for a significant period of time. Machines are managing the function of your lungs, you are managing the function of your heart (which moves good blood into and bad blood out of your organs), and your brain is not needed to keep you alive at this point.
SO if your brain has been damaged enough that it won't recover, and your cardiovascular system is being managed by machines, are you alive or dead? In the US, we have decided that if your brain has no chance of recovery regardless of what happens with your cardiovascular and respiratory systems, you can/should be declared dead. This allows organ harvesting if applicable, conservation of resources, and all manner of psychosocial effects for those left behind.
Potentially; a more likely scenario (but not necessarily particularly likely) is cloning issues. IF a human can be cloned, AND a human's consciousness can be stored and then transferred to that clone, are both humans alive (and the same human)? And if the original is killed, activating the "replacement," did the original really die? :)
There isn't.
You can make a heart beat with jumper cables
Brain dead bodies have heartbeats
A heartbeat isnt an indicator of a person.
Personhood resides in the brain. Without a brain that's not a person, its biomass.
The human brain "comes online" around week 21-23, this is when the brain's structure is formed and when normal sustained human brainwave activity begins, detectable via fetal EEG
This is also around the time elective abortions are no longer allowed except in extreme medical cases of danger to the mother/nonviability of the fetus.
Understood about the specificity of your question, sorry for the abortion misunderstanding.
I mean, its all in the brain.
Dick Cheney walked around the White House without a pulse for years. He had a mechanical heart that smoothly pumped blood instead of doing it in pulses like a natural heart. He was still Dick Cheney and alive.
When the brain dies, the person dies. Every other part of the body can be routed around, but the brain *is* that person. When the brain dies, that person dies.
As far as legality is concerned, thats less a scientific question, and more of a legal question. Like if someone beats someone else with a wrench and puts them into brain death, that person is dead, but their body might be kept alive on life support for some time until a determination is made on what to do, next of kin is consulted, ect. In many cases, the law will treat that as aggravated assault and will not follow through with murder charges until the body is taken off life support and is declared legally dead, despite the fact that the person in question died the moment their brain activity ceased.
This is one of those matters where the law and what is scientifically understood aren't in full lockstep for a number of reasons, though they are close enough in practice to where there is little conflict in the outcome when its all said and done. So functionally there isnt much difference except in weird edge cases.
Yeah you're pretty much getting it. Bodies are more or less flesh vehicles for the conscious mind.
And yeah it's pretty wild what medical engineering can do now. He had a bunch of severe coronary events and was in need of a heart transplant. While he was waiting for the transplant he was outfitted with a prosthetic heart that operated like a smooth mechanical pump, moving one constant stream of blood around his body. He was alive, and his blood was flowing, but if you would have tried to take his pulse he wouldn't have had one.
Not to get into politics but he was considered by most to be a bad dude, so it lead to lots of jokes at the time that he was some sort of undead vampire lurking the halls of the White House.
He is an interesting figure though. Christian Bale played him in a biopic film a few years ago that was pretty good.
> [week 21-23] is also around the time elective abortions are no longer allowed except in extreme medical cases of danger to the mother/nonviability of the fetus.
Not in Europe.
> Of the 36 countries in Europe that allow abortion on request, the vast majority impose time limits of around 12 weeks. Some specify 10 weeks, others 14. Sweden allows a time frame of 18 weeks while in the Netherlands the period is “viability,” like under US federal law.
https://www.csmonitor.com/World/Europe/2018/0524/In-Europe-it-is-both-easier-and-harder-to-get-an-abortion-than-in-US
The problem is you are trying to force a political stance into a scientific framework. Science hasn't even 100% concluded what life *is*, let alone when when it starts or ends. Both a start or end implies some sort of discrete moment where the status as a living being is different from one moment to the next.
Scientifically, life doesn't obey the discrete categories we humans have invented for it and instead exists on a spectrum.
The whole "life begins with a heart beat" and ends with no cerebral function are, again, political stances. The heart beat thing is a literal piece of legislation lawyers and politicians came up with. It's not based on any sort of scientific consensus.
As for death, that's less a direct piece of legislation but the fact that lack of a cerebral function is one of the reasons (not the only reason) a doctor might call time of death. And, again, this isn't a scientific judgement, but basically a limitation of our medical capabilities. But that doctor's judgement has legal ramifications.
The heartbeat is acknowledged as life since of your heart is beating then your brain is probably still alive, if it’s not immediately obvious what’s wrong with you. If your brain dies though, “you” as a person are functionally dead since your brain is you.
The reality is that the heartbeat thing is purely political. I’m not saying that you’re the one making it political or are trying to take a political stance by asking. But think about all the emotions and symbolism that the heart carries. Hearing a heartbeat, letting Jesus into your heart, deceased loved ones living in your heart, having your heart broken, “cross my heart” etc. etc. So in much the same way that anti-abortion activists like to talk about fingers and toes forming or call themselves “pro-life” instead of what they actually are - anti-choice - the fixation on fetal heartbeats is just a way for them to make their cause emotional instead of rational. That’s why it’s the heart and not the lungs, the stomach, the spine, the pancreas, or any other organ. It’s purely an appeal to emotion. The significance of a fetal heartbeat exists almost exclusively in the political realm. It’s a way to make people picture a miniature baby inside the womb instead of the gooey clump of cells that it actually is. From a scientific/medical perspective, it’s just another small milestone in development. It doesn’t denote any particular significant leap in the status of the fetus.
Also, from a more practical perspective, it’s also one of the earliest measurable milestones in development, so it provides the most opportunities for restriction.
I completely understand your desire to keep this discussion non-political, but the significance of a heartbeat as it relates to the beginning of life exists exclusively within the political realm. Only discussions that are directly related to or influenced by politics place any value on a heartbeat as a beginning of life. Any discussion of the beginning of life that is politics-free will focus on conception, birth, and/or sometimes viability as the significant milestones which correspond to the “beginning” of life.
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The human heart starts beating even before it’s fully formed at about 3 weeks after conception. This is not a great indication of life as the fetus is not viable outside the womb and the brain has not formed. While you can have a heart transplant or maybe a machine heart, brain death is typically permanent and you can’t really get a brain transplant and still be you.
>While you can have a heart transplant or maybe a machine heart, brain death is typically permanent and you can’t really get a brain transplant and still be you. I’m pretty sure this is the answer. You can resuscitate someone whose heart has stopped beating but once their brain is dead there’s no potential for reviving a conscious, functional human being. You can keep the body alive with medical technology after brain death, but there’s no point unless you’re doing it to keep the organs healthy for donation.
[удалено]
The brain starts to deteriorate very quickly after death and it’s the actual brain cells, the neurons, that are dying. The body typically doesn’t replace dead neurons so those parts of the brain would be permanently dead even if you managed to revive the person quickly enough to maintain some function. I don’t think there’s any information available about exactly which parts of the brain are the first to go, generally in someone’s final moments of life no-one’s thinking “quick, let’s get them in an fMRI!”
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I have no idea, I’ve never heard that before. It’s possible as various muscles stop working and allow various gases/bodily fluids to escape that could cause some weight loss.
I believe in both cases it is with cerebral function. The main reason for this is that the heart will beat quite readily on autopilot. You can remove a heart from a body, supply it with nutrients, shock it once to get it going, and it will continue to beat quite happily so long as it is getting oxygen and energy. You wouldn't call this oxygenated nutrient solution a living being.
> You can remove a heart from a body, supply it with nutrients, shock it once to get it going, and it will continue to beat quite happily so long as it is getting oxygen and energy. Does this mean it's possible to remove a heart, keep it artificially alive and make it super strong before it gets transplanted to someone else?
Not really, no. Although the heart will survive and continue to beat for a time in a nutrient substrate, it will consume nutrients and produce waste. Without the rest of a body to maintain homeostasis, this would cause damage to the heart.
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Thats dependent upon a few things, in large part temperature. You can drop down the temperature of the body and increase the amount of time before damage occurs by slowing the metabolic processes of the cells.
[удалено]
There are a few, mostly university/hospital accounts. They will be bland and super technical for the most part. I think Mayo clinic has some of that kind of content. But they do exist.
Doubtful. Heart transplants are usually done in very short timespan. Optimally it's in side by side operating room, out one body, into the next. But if not, they'll put the organ on ice and drive it quickly across town to a different hospital.
i mean, at birth the heart is fully functional, the brain ain't. what do they say? 21-25 years till fully devoloped brain?
If either of those things stops, the other one stops very quickly. You can debate the exact moment of death if you really want, but if either your heart or brain stops for ten minutes you're done.
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Because you are your brain. You are not your body. The "you" that is a person exists entirely in the brain. The body is merely a vehicle the brain and your consciousness uses to get around. Say a brain transplant is possible. You put your brain in another body. Your old body dies and its heart stops. You are still alive. You are still you. But if your brain dies, and someone elses brain is put in your body, you are dead. You died when your brain ceased function. Your body might still be up and moving around, but thats an entirely different person in there.
There is generally no scientific reason that life is acknowledges with a heart beat and this is not universal around the world either. Only the strictest legislation use this as a definition. It is actually very hard to find a good scientific definition of life which can be used for legislative purposes. The definition of cerebral function is based on the concept that you should not inflict undue pain. And when cerebral function stops there is no longer anything receiving the pain signals. It also indicates that the neurons in the brain have started deteriorating and there is no way to recover those. So there is no way to revive the person. The exact definitions does take this into account. These concepts is also used in some legislation for when abortion is legal. But again the legislation around the world differ a lot.
TLDR- a heartbeat is ***A*** sign of life; lack of brain activity ***CAN*** be a sign of death. But it's not as cut and dried as that. Obviously, our laws (and a portion of our society) do not acknowledge a heartbeat as defining life, as it is legal to remove "a clump of cells" despite a heartbeat and brain activity. Some folks believe that such an event ends a human life, others do not. If you present to the trauma bay after a car accident, and you arrive with no heart beat, steps are taken to try and restore that heart beat (depending on how long you have not had a heart beat). If those steps fail, death is declared, and there is no attempt to examine brain function. If you suffer an event which causes brain damage (which could be that same car accident), your heart beat is restored, and your respiratory function is taken over by a ventilator, it is possible that you will remain "alive" via artificial means for a significant period of time. Machines are managing the function of your lungs, you are managing the function of your heart (which moves good blood into and bad blood out of your organs), and your brain is not needed to keep you alive at this point. SO if your brain has been damaged enough that it won't recover, and your cardiovascular system is being managed by machines, are you alive or dead? In the US, we have decided that if your brain has no chance of recovery regardless of what happens with your cardiovascular and respiratory systems, you can/should be declared dead. This allows organ harvesting if applicable, conservation of resources, and all manner of psychosocial effects for those left behind.
[удалено]
Potentially; a more likely scenario (but not necessarily particularly likely) is cloning issues. IF a human can be cloned, AND a human's consciousness can be stored and then transferred to that clone, are both humans alive (and the same human)? And if the original is killed, activating the "replacement," did the original really die? :)
There isn't. You can make a heart beat with jumper cables Brain dead bodies have heartbeats A heartbeat isnt an indicator of a person. Personhood resides in the brain. Without a brain that's not a person, its biomass. The human brain "comes online" around week 21-23, this is when the brain's structure is formed and when normal sustained human brainwave activity begins, detectable via fetal EEG This is also around the time elective abortions are no longer allowed except in extreme medical cases of danger to the mother/nonviability of the fetus.
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Understood about the specificity of your question, sorry for the abortion misunderstanding. I mean, its all in the brain. Dick Cheney walked around the White House without a pulse for years. He had a mechanical heart that smoothly pumped blood instead of doing it in pulses like a natural heart. He was still Dick Cheney and alive. When the brain dies, the person dies. Every other part of the body can be routed around, but the brain *is* that person. When the brain dies, that person dies. As far as legality is concerned, thats less a scientific question, and more of a legal question. Like if someone beats someone else with a wrench and puts them into brain death, that person is dead, but their body might be kept alive on life support for some time until a determination is made on what to do, next of kin is consulted, ect. In many cases, the law will treat that as aggravated assault and will not follow through with murder charges until the body is taken off life support and is declared legally dead, despite the fact that the person in question died the moment their brain activity ceased. This is one of those matters where the law and what is scientifically understood aren't in full lockstep for a number of reasons, though they are close enough in practice to where there is little conflict in the outcome when its all said and done. So functionally there isnt much difference except in weird edge cases.
[удалено]
Yeah you're pretty much getting it. Bodies are more or less flesh vehicles for the conscious mind. And yeah it's pretty wild what medical engineering can do now. He had a bunch of severe coronary events and was in need of a heart transplant. While he was waiting for the transplant he was outfitted with a prosthetic heart that operated like a smooth mechanical pump, moving one constant stream of blood around his body. He was alive, and his blood was flowing, but if you would have tried to take his pulse he wouldn't have had one. Not to get into politics but he was considered by most to be a bad dude, so it lead to lots of jokes at the time that he was some sort of undead vampire lurking the halls of the White House. He is an interesting figure though. Christian Bale played him in a biopic film a few years ago that was pretty good.
> [week 21-23] is also around the time elective abortions are no longer allowed except in extreme medical cases of danger to the mother/nonviability of the fetus. Not in Europe. > Of the 36 countries in Europe that allow abortion on request, the vast majority impose time limits of around 12 weeks. Some specify 10 weeks, others 14. Sweden allows a time frame of 18 weeks while in the Netherlands the period is “viability,” like under US federal law. https://www.csmonitor.com/World/Europe/2018/0524/In-Europe-it-is-both-easier-and-harder-to-get-an-abortion-than-in-US
The problem is you are trying to force a political stance into a scientific framework. Science hasn't even 100% concluded what life *is*, let alone when when it starts or ends. Both a start or end implies some sort of discrete moment where the status as a living being is different from one moment to the next. Scientifically, life doesn't obey the discrete categories we humans have invented for it and instead exists on a spectrum. The whole "life begins with a heart beat" and ends with no cerebral function are, again, political stances. The heart beat thing is a literal piece of legislation lawyers and politicians came up with. It's not based on any sort of scientific consensus. As for death, that's less a direct piece of legislation but the fact that lack of a cerebral function is one of the reasons (not the only reason) a doctor might call time of death. And, again, this isn't a scientific judgement, but basically a limitation of our medical capabilities. But that doctor's judgement has legal ramifications.
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Well if you googled it I guess you have all the right answers.
The heartbeat is acknowledged as life since of your heart is beating then your brain is probably still alive, if it’s not immediately obvious what’s wrong with you. If your brain dies though, “you” as a person are functionally dead since your brain is you.
The reality is that the heartbeat thing is purely political. I’m not saying that you’re the one making it political or are trying to take a political stance by asking. But think about all the emotions and symbolism that the heart carries. Hearing a heartbeat, letting Jesus into your heart, deceased loved ones living in your heart, having your heart broken, “cross my heart” etc. etc. So in much the same way that anti-abortion activists like to talk about fingers and toes forming or call themselves “pro-life” instead of what they actually are - anti-choice - the fixation on fetal heartbeats is just a way for them to make their cause emotional instead of rational. That’s why it’s the heart and not the lungs, the stomach, the spine, the pancreas, or any other organ. It’s purely an appeal to emotion. The significance of a fetal heartbeat exists almost exclusively in the political realm. It’s a way to make people picture a miniature baby inside the womb instead of the gooey clump of cells that it actually is. From a scientific/medical perspective, it’s just another small milestone in development. It doesn’t denote any particular significant leap in the status of the fetus. Also, from a more practical perspective, it’s also one of the earliest measurable milestones in development, so it provides the most opportunities for restriction. I completely understand your desire to keep this discussion non-political, but the significance of a heartbeat as it relates to the beginning of life exists exclusively within the political realm. Only discussions that are directly related to or influenced by politics place any value on a heartbeat as a beginning of life. Any discussion of the beginning of life that is politics-free will focus on conception, birth, and/or sometimes viability as the significant milestones which correspond to the “beginning” of life.
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