6 ms·

Electrical signatures of consciousness in the dying brain

33 points by daegloe 13y ago

D9u 13y ago
How are we to know what happens after death? If electrical energy is what constitutes brain activity, then what happens to that energy when death occurs? http://en.wikipedia.org/wiki/First_law_of_thermodynamics http://en.wikipedia.org/wiki/First_law_of_thermodynamics What is the transformation that takes place, if any? Is there more to existence than we are capable of understanding?
- narag 13y ago
  If electrical energy is what constitutes brain activity, then what happens to that energy when death occurs? What happens to electrical energy in a computer when we switch it off? I'd say that nothing very interesting. "Constitutes" is also somewhat ambiguous. It's the structure of that electrical currents that depends on neural connections what I would say brain activity is. Once the neurons are unusable, the energy by itself is just dispersed, mere electrons with no shape. So we... die.
- andyjohnson0 13y ago
  "what happens to that energy when death occurs?" It's lost as heat. The brain is an electro-chemical system [1][2]. That is, signals propagate via potential differences created by the presence of charged ions. In the prolonged absence of oxygen, the biochemistry of the brain ceases at a cellular level. Electrical potential differences smooth-out to the level of thermal noise. Anything left radiates out as heat until the body reaches the ambient temperature of its environment. The radiated energy still exists in the universe, but the second law of thermodynamics implies that it is unlikely to be participating in a low-entropy system like a brain again. [1] http://psychology.wikia.com/wiki/Chemical_synapse http://psychology.wikia.com/wiki/Chemical_synapse [2] http://science.howstuffworks.com/life/human-biology/human-body-make-electricity.htm http://science.howstuffworks.com/life/human-biology/human-bo... EDIT I have a hard time with talking of "transformation" of electrical patterns in dying brains and "Is there more to existence than we are capable of understanding?". I don't really know what these questions mean. I've seen a couple of people die in front of me and its a deeply upsetting experience that is charged with meaning. But thats on the level of human emotional experience. On a physical level, death is just something that bodies do at some point before their constituent matter and energy goes off to do other things in the universe. Trying to unload human emotional baggage relating to human existence (principally, fear of death) onto physical processes that are pretty well understood (biochemistry) gets us nowhere, because really where do you stop?
  - cryofan 13y ago
    however, if the structure of the brain is preserved in liquid nitrogen for hundreds of years, the brain may then be revived and placed into another body, repaired and restarted, and the person may live again. After death, autolysis destroys the structure of the brain if the brain is left at room temp for a day or so. However, the application of ice to the brain soon after death will prevent this by lowering temps to near zero C, which slows autolysis greatly. The brain may then be taken down to liquid nitrogen temps and preserved in a dewar or cryostat for hundreds or even thousands of years.
  - D9u 13y ago
    Thanks for your comment, as I clearly had erroneous preconceived notions regarding this subject.
gfody 13y ago
I don't know if they can claim "the first scientific framework for the near-death experience". Dr. Strassman (http://www.rickstrassman.com http://www.rickstrassman.com) experimented on humans in the mid 90's could consistently reproduce near-death experiences by administering DMT intravenously.
- girvo 13y ago
  Having administered DMT intravenously to myself... an NDE isn't a bad way of putting it, to be honest.
  - delluminatus 13y ago
    Would you recommend the experience? How does it compare to more traditional DMT administration (i.e. smoking)?
    - girvo 13y ago
      Depends on what sort of grip you have on your world. I'd suggest it, but only if you've already crossed the line into Needles anyway: once you have gone there, if you take drugs recreationally at all, you will start doing it with everything. So, no, not really worth it, unless you're willing to make that choice.
- spurgu 13y ago
  I would be curious to see a comparison of the electrical activity of an NDE with someone taking DMT.
megfitz 13y ago
"“It will form the foundation for future human studies investigating mental experiences occurring in the dying brain, including seeing light during cardiac arrest,” she says." I am a big fan of science and research - and I think we should always be questioning everything. But I'm curious to know what benefits this research has. I genuinely don't know where this kind of research could lead so I'm not naive enough to suggest it's not a good use of time or resources, but how can this help us improve our lives, health and world? Does it matter? Not to be crass, but are those last vestiges of electrical energy in a dying brain going to be of any use?
- jbri 13y ago
  Demanding that research show immediate practicality is a good way to end up doing no meaningful research whatsoever. Virtually every major discovery in the past hundred years (if not more) stems from research that had no obvious direct application. The biggest benefit of the post-industrial society is being able to spend time on things that aren't immediately useful, but potentially have greater benefits further down the road.
  - apl 13y ago
    Keep in mind that "All breakthroughs are derived from basic research" (if true) doesn't entail "All basic research leads to breakthroughs". We still need to judge the merit of basic research; in this case I'm slightly more skeptical as to its potential to unravel, well, anything about the mind at all.
    - jbri 13y ago
      I'm not saying that it is - but research for its own sake is worthwhile, even if you don't know beforehand how earthshaking the results will be. Sure, sometimes you swing and you miss, but if that makes you too scared to swing at all then you're never going to hit anything.
    - andyjohnson0 13y ago
      I agree with you on the need to use judgement. In this case though, while the research might not tell us much about the mind, knowing more about the regions of the brain that are active during an NDE could provide more insight into how the brain is physically affected by oxygen starvation. It might also help with designing physical and psychological therapies for the negative consequences [1] of near death experiences for survivors. It does seen like a lot of the discussion about this subject is (often implicitly) trying to address a religious/afterlife aspect of nde. For example, the article says 'The "near-death experience" reported by cardiac arrest survivors worldwide may be grounded in science'. The brain is a physical object that is subject to the laws of physics, so that "grounding" is inevitable whether we know how it works or not. This shouldn't be surprising and there isn't an alternative, short of admitting religion or parapsychology. [1] http://en.wikipedia.org/wiki/Near-death_experience#Effects http://en.wikipedia.org/wiki/Near-death_experience#Effects
narag 13y ago
That's very interesting. But I can't help feeling sorry for the poor asphyxiated rats.
adventured 13y ago
My favorite brain tale: http://en.wikipedia.org/wiki/Lavoisier http://en.wikipedia.org/wiki/Lavoisier Specifically: http://msgboard.snopes.com/message/ultimatebb.php?/ubb/get_topic/f/36/t/000797.html http://msgboard.snopes.com/message/ultimatebb.php?/ubb/get_t...
Tichy 13y ago
I dunno - isn't this the most useless experiment ever? The brain reacts to death throes of the body. Who would have thought? I would imagine being killed would be a pretty significant experience for the brain, and usually a completely new one. Also I was under the impression that clinical death implied that there are no more brain waves.

33 points by daegloe 13y ago

D9u 13y ago

How are we to know what happens after death? If electrical energy is what constitutes brain activity, then what happens to that energy when death occurs? http://en.wikipedia.org/wiki/First_law_of_thermodynamics http://en.wikipedia.org/wiki/First_law_of_thermodynamics What is the transformation that takes place, if any? Is there more to existence than we are capable of understanding?

narag 13y ago
If electrical energy is what constitutes brain activity, then what happens to that energy when death occurs? What happens to electrical energy in a computer when we switch it off? I'd say that nothing very interesting. "Constitutes" is also somewhat ambiguous. It's the structure of that electrical currents that depends on neural connections what I would say brain activity is. Once the neurons are unusable, the energy by itself is just dispersed, mere electrons with no shape. So we... die.
andyjohnson0 13y ago
"what happens to that energy when death occurs?" It's lost as heat. The brain is an electro-chemical system [1][2]. That is, signals propagate via potential differences created by the presence of charged ions. In the prolonged absence of oxygen, the biochemistry of the brain ceases at a cellular level. Electrical potential differences smooth-out to the level of thermal noise. Anything left radiates out as heat until the body reaches the ambient temperature of its environment. The radiated energy still exists in the universe, but the second law of thermodynamics implies that it is unlikely to be participating in a low-entropy system like a brain again. [1] http://psychology.wikia.com/wiki/Chemical_synapse http://psychology.wikia.com/wiki/Chemical_synapse [2] http://science.howstuffworks.com/life/human-biology/human-body-make-electricity.htm http://science.howstuffworks.com/life/human-biology/human-bo... EDIT I have a hard time with talking of "transformation" of electrical patterns in dying brains and "Is there more to existence than we are capable of understanding?". I don't really know what these questions mean. I've seen a couple of people die in front of me and its a deeply upsetting experience that is charged with meaning. But thats on the level of human emotional experience. On a physical level, death is just something that bodies do at some point before their constituent matter and energy goes off to do other things in the universe. Trying to unload human emotional baggage relating to human existence (principally, fear of death) onto physical processes that are pretty well understood (biochemistry) gets us nowhere, because really where do you stop?
- cryofan 13y ago
  however, if the structure of the brain is preserved in liquid nitrogen for hundreds of years, the brain may then be revived and placed into another body, repaired and restarted, and the person may live again. After death, autolysis destroys the structure of the brain if the brain is left at room temp for a day or so. However, the application of ice to the brain soon after death will prevent this by lowering temps to near zero C, which slows autolysis greatly. The brain may then be taken down to liquid nitrogen temps and preserved in a dewar or cryostat for hundreds or even thousands of years.
- D9u 13y ago
  Thanks for your comment, as I clearly had erroneous preconceived notions regarding this subject.

gfody 13y ago

I don't know if they can claim "the first scientific framework for the near-death experience". Dr. Strassman (http://www.rickstrassman.com http://www.rickstrassman.com) experimented on humans in the mid 90's could consistently reproduce near-death experiences by administering DMT intravenously.

girvo 13y ago
Having administered DMT intravenously to myself... an NDE isn't a bad way of putting it, to be honest.
- delluminatus 13y ago
  Would you recommend the experience? How does it compare to more traditional DMT administration (i.e. smoking)?
  - girvo 13y ago
    Depends on what sort of grip you have on your world. I'd suggest it, but only if you've already crossed the line into Needles anyway: once you have gone there, if you take drugs recreationally at all, you will start doing it with everything. So, no, not really worth it, unless you're willing to make that choice.
spurgu 13y ago
I would be curious to see a comparison of the electrical activity of an NDE with someone taking DMT.

megfitz 13y ago

"“It will form the foundation for future human studies investigating mental experiences occurring in the dying brain, including seeing light during cardiac arrest,” she says." I am a big fan of science and research - and I think we should always be questioning everything. But I'm curious to know what benefits this research has. I genuinely don't know where this kind of research could lead so I'm not naive enough to suggest it's not a good use of time or resources, but how can this help us improve our lives, health and world? Does it matter? Not to be crass, but are those last vestiges of electrical energy in a dying brain going to be of any use?

jbri 13y ago
Demanding that research show immediate practicality is a good way to end up doing no meaningful research whatsoever. Virtually every major discovery in the past hundred years (if not more) stems from research that had no obvious direct application. The biggest benefit of the post-industrial society is being able to spend time on things that aren't immediately useful, but potentially have greater benefits further down the road.
- apl 13y ago
  Keep in mind that "All breakthroughs are derived from basic research" (if true) doesn't entail "All basic research leads to breakthroughs". We still need to judge the merit of basic research; in this case I'm slightly more skeptical as to its potential to unravel, well, anything about the mind at all.
  - jbri 13y ago
    I'm not saying that it is - but research for its own sake is worthwhile, even if you don't know beforehand how earthshaking the results will be. Sure, sometimes you swing and you miss, but if that makes you too scared to swing at all then you're never going to hit anything.
  - andyjohnson0 13y ago
    I agree with you on the need to use judgement. In this case though, while the research might not tell us much about the mind, knowing more about the regions of the brain that are active during an NDE could provide more insight into how the brain is physically affected by oxygen starvation. It might also help with designing physical and psychological therapies for the negative consequences [1] of near death experiences for survivors. It does seen like a lot of the discussion about this subject is (often implicitly) trying to address a religious/afterlife aspect of nde. For example, the article says 'The "near-death experience" reported by cardiac arrest survivors worldwide may be grounded in science'. The brain is a physical object that is subject to the laws of physics, so that "grounding" is inevitable whether we know how it works or not. This shouldn't be surprising and there isn't an alternative, short of admitting religion or parapsychology. [1] http://en.wikipedia.org/wiki/Near-death_experience#Effects http://en.wikipedia.org/wiki/Near-death_experience#Effects

narag 13y ago

That's very interesting. But I can't help feeling sorry for the poor asphyxiated rats.

adventured 13y ago

My favorite brain tale: http://en.wikipedia.org/wiki/Lavoisier http://en.wikipedia.org/wiki/Lavoisier Specifically: http://msgboard.snopes.com/message/ultimatebb.php?/ubb/get_topic/f/36/t/000797.html http://msgboard.snopes.com/message/ultimatebb.php?/ubb/get_t...

Tichy 13y ago

I dunno - isn't this the most useless experiment ever? The brain reacts to death throes of the body. Who would have thought? I would imagine being killed would be a pretty significant experience for the brain, and usually a completely new one. Also I was under the impression that clinical death implied that there are no more brain waves.