People In Comas Showed 'Conscious-Like' Brain Activity As They Died, Study Says (theguardian.com) 65
An anonymous reader quotes a report from The Guardian: Some recall bright lights at the end of a tunnel, feeling the presence of loved ones or floating above their body after a near-death experience. Now, scientists say they have captured "conscious-like" brain activity in dying patients in findings that give new insights into the process of death. The study used data from four patients who had died in hospital while their brains were being monitored using EEG recordings because they had previously suffered suspected seizures. All four of the patients were comatose and unresponsive and had been deemed beyond medical help. With their families' permission, life support had been withdrawn and they had subsequently suffered cardiac arrest and died.
The scientists retrospectively analyzed the brain activity data in the moments after life support was withdrawn until the patients' deaths. Upon removal of ventilator support, two of the patients showed an increase in heart rate along with a surge of gamma wave activity, considered the fastest brain activity and associated with consciousness. The activity was detected in the so-called hot zone, an area in the back of the brain linked to conscious brain activity. This area has been correlated with dreaming, visual hallucinations in epilepsy, and altered states of consciousness in other brain studies. The other two patients did not display the same increase in heart rate or brain activity, according to the study published in the Proceedings of the National Academy of Sciences. Scientists said it was impossible to know exactly what the brain activity might correspond to as a subjective experience.
The scientists retrospectively analyzed the brain activity data in the moments after life support was withdrawn until the patients' deaths. Upon removal of ventilator support, two of the patients showed an increase in heart rate along with a surge of gamma wave activity, considered the fastest brain activity and associated with consciousness. The activity was detected in the so-called hot zone, an area in the back of the brain linked to conscious brain activity. This area has been correlated with dreaming, visual hallucinations in epilepsy, and altered states of consciousness in other brain studies. The other two patients did not display the same increase in heart rate or brain activity, according to the study published in the Proceedings of the National Academy of Sciences. Scientists said it was impossible to know exactly what the brain activity might correspond to as a subjective experience.
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No, Biden makes sense, not insults. Explains you.
whoaa I'm suffocating (Score:5, Insightful)
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that's what i was thinking.
seems like you would have a major flood of adrenaline and whatever other chemicals your body could bring to bear to try and get you started again.
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Prolonged cerebral hypoxia (through e.g. reduced blood flow) or anoxia induces neuronal cell death through apoptosis. An hour after drowning, the internal structure of your brain is gone.
Re:whoaa I'm suffocating (Score:4, Informative)
Prolonged cerebral hypoxia (through e.g. reduced blood flow) or anoxia induces neuronal cell death through apoptosis. An hour after drowning, the internal structure of your brain is gone.
Not (quite) always. The mammalian diving reflex can mitigate this to some extent. That's why a number of people have recovered after almost an hour underwater, and one very young kid who was under for 20 minutes recovered after 101 minutes of CPR, which would be more than two hours without a pulse.
That said, if you require more than half an hour of resuscitation, your odds aren't very good [bmj.com]. In that Dutch retrospective analysis, the 11% resuscitated for that long who survived were all either severely neurologically impaired or in a vegetative state afterwards. So that one case where the kid survived 20 minutes underwater and 101 minutes of CPR is probably bordering on lottery ticket odds. But things like that do happen every so often.
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Maybe provide some links, 'cause this [bmj.com] doesn't look good. Looks like 25 min is about tops.
Two hour without a natural pulse. CPR ventilates the lungs and circulates blood.
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Maybe provide some links, 'cause this [bmj.com] doesn't look good. Looks like 25 min is about tops.
You're misreading that. Those numbers are the number of minutes of resuscitation *after* they pull the victim out of the water. If you read that paper carefully (at least I think it was the same paper), you'll find out that the odds of survival are much higher in winter because of the cold temperatures, and that this results in lower resuscitation times, assuming all else is equal.
Basically, the amount of time spent resuscitating someone is usually a good indication of how brain damaged they are. But occ
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Re:whoaa I'm suffocating (Score:5, Informative)
I do wonder, why once someone say.. drowns. After about an hour, why you can not revive them?
Occasionally you can. The brain normally suffers permanent and irreversible damage after oxygen deprivation for about ten minutes at normal temperatures. But there's something called the mammalian diving reflex that triggers when your face is submerged in cold water, which triggers a bunch of physiological changes. One of those changes is a massive reduction in energy and oxygen consumption by the central nervous system to prolong survival in near-drowning situations.
This behavior is not universal — only about 15% of people exhibit this phenomenon [nih.gov], which is presumably a vestigial function from before our distant ancestors crawled out of the oceans — but for those who do, that is believed to be why so many people survive near-drowning for extended periods of time. As the expression goes, "You're not dead until you're warm and dead."
The record to date involved an infant who was submerged for twenty minutes followed by a whopping one hour, forty-one minutes of CPR performed by a chain of fifty people.
But there's more. Normally, cells die when they don't have oxygen, to make way for new cells. The problem is that central nervous system cells regrow too slowly for this to be a good idea, not to mention that the loss of those cells results in a loss of... well, what makes you you.
However, it may be possible to prevent, or at least reduce, the mass catastrophic apoptosis of central nervous system cells, allowing at least some of the cells to repair themselves. There's a chemical commonly used for dying laboratory slides called methylene blue. When injected intravenously, it triggers an uptick in adenosine triphosphate production, which has a neuroprotective effect. It also has an antioxidant behavior, which is apparently unusual in chemicals that stimulate ATP production.
Anyway, in one study involving rats, researchers triggered an ischemic stroke. The group of rats that got MB ended up with 30% less dead brain tissue [nih.gov] after an induced ischemic stroke than the group that got saline. Also, for all of the rats in the MB group, the size of the damaged area decreased between the initial observation and the final observation in the MB group, rather than increasing as it typically does in an ischemic stroke (and did for all of the rats in the non-MB group).
The truly remarkable thing is that this study has been repeated multiple times, and one recent study in 2021 even showed a dramatic reduction in brain damage when MB is given an entire day after [hindawi.com] the induced stroke. So there's at least a nonzero chance that that the right answer to your question might someday be "we can", though that's a subject for future studies. :-)
There have also been studies showing MB to be beneficial in cases of septic shock [jvsmedicscorner.com]. Also there was a study showing that it was helpful in cases of ifosfamide-induced encephalopathy [sagepub.com] (brain injury resulting from cancer treatment). And there have apparently been multiple studies on Alzheimer's, at least one of which was promising, at least in the early stages [nih.gov]. (It was sadly but unsurprisingly entirely useless at reducing the progression of COVID-19.)
But for some reason, as far as I can tell, there have still been no trials on MB in humans after ischemic strokes, drownings, heart attacks, etc., even though it is FDA approved for use in humans and could be off-label tested rather easily. We've known about its neuroprotective effects
Re:whoaa I'm suffocating (Score:5, Interesting)
Our brain is a pretty complex thing and very fragile. And very oxygen dependent. 20% of all the oxygen you breathe is exclusively for your brain. Which is about ten times of what its "share" is, by weight.
Oxygen is also something our body can't really "store" well. This is actually what we should ask, why can we store fat, water and even some vitamins for a couple days or even months (or in the case of fat, a lifetime...), but only a few minutes without air and we're dead.
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This is actually what we should ask, why can we store fat, water and even some vitamins for a couple days or even months (or in the case of fat, a lifetime...), but only a few minutes without air and we're dead.
I'm not an expert but I'm guessing a part of it is that air has such a low density, so storing any significant amount of it would require a lot of volume. I imagine trying to compress that air would be difficult and would have its own problems - I know that at above a certain concentration oxygen actually becomes toxic - probably because it's so reactive.
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I'm guessing that because O2 has been universally available on-demand for a geologically long time, there was never a need to store it once animals came along. That is, except for the mammals who spend significant time under water, and they develop strategies for such storage.
Food, on the other hand, is not universally available on-demand to individual organisms on an evolutionary scale, so a means of storage was critical to develop. That idea also explains why in mammals, fructose has an express lane to
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Oxygen is also something our body can't really "store" well. This is actually what we should ask, why can we store fat, water and even some vitamins for a couple days or even months (or in the case of fat, a lifetime...), but only a few minutes without air and we're dead.
Oxygen is a weird one. Although we require it to exist, it is extremely reactive and toxic. https://en.wikipedia.org/wiki/... [wikipedia.org]
Which is mind numbingly counterintuitive.
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Only at first glance, until you realize that Oxygen, and it becoming available in our atmosphere, is probably the most deadly event [wikipedia.org] in the history of our planet.
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Only at first glance, until you realize that Oxygen, and it becoming available in our atmosphere, is probably the most deadly event [wikipedia.org] in the history of our planet.
Exactly. While making present day life forms possible, it damn near turned the place sterile. It did give us concentrated iron deposits when the oceans rusted, so that was nice.
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Which is mind numbingly counterintuitive.
Is it?
I think I'd expect any good fuel source to be particularly.... unpleasant (reactive).
The trend generally follows for technological fuel sources as well.
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Which is mind numbingly counterintuitive.
Is it?
I think if we asked a hundred people if Oxygen was poisonous, 98 would say we were full of BS.
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That said, I get your point, but I consider it more of an indictment of the educational level of those hundred people.
Oxidation should have been covered in high school.
Re:whoaa I'm suffocating (Score:4, Interesting)
I do wonder, why once someone say.. drowns. After about an hour, why you can not revive them? What in the body changes an hour after drowning
There is nothing mystical or unknown about what happens when you drown. Your "one hour" number above is some kind of nonsense or old wives tale. (It could also be that someone was in the water -- not underwater -- for an hour, and the advice was to not bother trying to revive them.) The main problem is that your brain starts dying pretty quickly. After that, you're going to also have a (quite likely fatal) heart attack. This all happens within a few minutes, not an hour.
Your brain starts dying about one minute after you drown, and after 3 minutes you're probably going to have permanent brain damage. After 5 or 6 minutes, it's unlikely your brain will still work at all. The current record for survival is abut 8 minutes (female) and 11 minutes (male). That's with brain damage, though.
When you revive someone who was drowned for over 3 minutes, they're going to have very serious permanent brain damage.
If they are ever conscious again, they will probably have psychological and cognitive damage, perhaps a "vegetable". They may have trouble moving their body parts. They may have to be on artificial life support forever. Because, you see, what happened is that they died.
You may see a reference to a diver who survived 30 minutes after his oxygen line was cut. In that case, he still had a little oxygen in his suit and he tried to breathe very little. He did go unconscious and had to be revived when they finished pulling him up. He is apparently OK. But he was not actually without any oxygen for most of that time.
There have also been cases involving drowning in very, very cold water. That can cause the oxygen consumption to go way down, and stretch those numbers out a bit. When you see a story about someone who "survived 2 hours of drowning", that's a misleading headline. They were notunderwater for hours. It was really only a few minutes, and after they pulled them out they were almost dead (e.g. no pulse), but then with extraordinary life support measures, they woke them up 2 hours after they had fallen in the water.
Reperfusion injury (Score:5, Interesting)
Much of the damage to the brain after recovery from oxygen deprivation is actually a result of bringing oxygen back into the organ. It sets off waves of apoptosis. Until you do this, the damage to the brain is not quite so extreme as you're making out.
Drugs that suppress this apoptosis show great promise.
People who have had no heartbeat for an extended period may still be revivable with the right techniques, even at room temperature.
https://en.wikipedia.org/wiki/... [wikipedia.org]
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There is nothing mystical or unknown about what happens when you drown. Your "one hour" number above is some kind of nonsense or old wives tale. (It could also be that someone was in the water -- not underwater -- for an hour, and the advice was to not bother trying to revive them.) The main problem is that your brain starts dying pretty quickly. After that, you're going to also have a (quite likely fatal) heart attack. This all happens within a few minutes, not an hour.
Your brain starts dying about one minute after you drown, and after 3 minutes you're probably going to have permanent brain damage. After 5 or 6 minutes, it's unlikely your brain will still work at all. The current record for survival is abut 8 minutes (female) and 11 minutes (male). That's with brain damage, though.
When you revive someone who was drowned for over 3 minutes, they're going to have very serious permanent brain damage.
Are you just making up numbers? You speak with confidence but your numbers make no sense. 3 minutes? I can hold my breath for 3 minutes but you claim that causes permanent brain damage. You also claim the "record" for survival is 8/11 minutes but there are hundreds or thousands of cases where victims survived without air for longer than that. Heck, the world record for holding your breath is 11:35. Here's a case [wired.co.uk]where 7 teenagers drowned and were resuscitated up to SIX HOURS later, quite a bit longer
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Have a friend(?) hold your mouth/nose to keep you from cheating. A very, very different experience and one you can try right now without a great detriment.
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Are you just making up numbers? You speak with confidence but your numbers make no sense. 3 minutes?
To sum up, don't just make shit up on the internet, it's too easy to fact check. If you don't know then don't act like you know.
I got the information from medical sites on the Internet. Perhaps those materials were written by ChatGPT.
I didn't check Wikipedia but some other commenter seemed to think it agrees with me.
Note that "breath holding" is not the same thing as "brain has no oxygen" and it's also a different thing that drowning. I think I'm right and you're confused.
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Back in the 1990's we had a lone server, which the Disk failed. However it did one job, rather well, thus the task was running in Ram, and didn't need the disk. This was a cheap server, without hotswap drives. but it was on a UPS. So it was left running for about a year. Once finally the OS crashed, or was unpowered for long enough. The Computer would no longer boot back up, to do its thing, because when the power went out, it lost its instructions to operate.
When our cells begin to grow into specialized
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You'd be shocked how quickly living tissue starts breaking down from it's living state once it stops getting oxygen, some form of sustenance, and relief from its own waste. Especially the parts of you that make you you. A couple minutes? Maybe. An hour? Without something keeping the tissues alive without the infrastructure, nope. No way.
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Coagulation. No blood movement for an hour almost guarantees some. Even if you get the heart pumping, now you've got clots to worry about - probably many.
It's not like if you drown, things just stop and wait.
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Cell death.
After a certain amount of time, cells without oxygen undergo irreversible destruction.
I'd think if you were serious about trying to figure out if a soul were really needed, you'd be wondering why someone can be brought back with half the soul they used to have. Did it only partially depart?
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Re:whoaa I'm suffocating (Score:5, Insightful)
I'm not a physician but I'm pretty sure reaction to co2 increase (you don't detect lack of O2 that's why you can die peacefully by breathing helium) is not handled by "area in the back of the brain linked to conscious brain activity". I at least expect these scientists to detect a different activity.
Nitrogen asphyxiation works that way as well. To the point that it makes sense as a capital punishment method. The present methods are weird and inefficient, and sometimes ridiculously complicated. Perhaps they only serve as instruments of vengeance?
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Slowly declining serum O2 levels is a hideously unpleasant way to go.
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Anoxia, unless very rapid, is a very not-fun way to go.
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How is it a wive's tale?
Because it is.
This has been used for assisted suicide.
Breathing helium? Only if you breathe 100% helium, leading to very rapid loss of consciousness.
Panic is induced by co2 level not o2 deprivation.
Incorrect.
Look up the symptoms for anoxia. Low serum (and consequently tissue) O2 levels leads to severe panic.
Obviously living in an oxygen deprived atmosphere may lead to ugly and painful medical conditions.
Any time spent int he regime where your body is hypoxic becomes quickly "ugly".
Due to the way the lungs work, completely oxygen-less environments (with some kind of breathable replacement gas) can be quite humane, simply because the lungs will work in reverse and exchange their O2 with th
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Breathing helium? Only if you breathe 100% helium, leading to very rapid loss of consciousness.
Exactly, that's what i'm saying from the start 0% oxygen but you keep talking about chronic low oxygen level exposition. Maybe my statement was not clear, english is not my native language.
Look up the symptoms for anoxia. Low serum (and consequently tissue) O2 levels leads to severe panic. Your body is more than able to detect hypoxic conditions
Lack of panic and other obvious symptoms when breathing low oxygen air is exactly why it is a source of common accident when using a rebreather for diving .
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Lack of panic and other obvious symptoms when breathing low oxygen air is exactly why it is a source of common accident when using a rebreather for diving .
Incorrect.
You are conflating a real problem of a CCR with your perceived undetectable-hypoxia problem.
CCRs, particularly during ascent phase can supply an insufficient partial pressure of O2 to the diver. This, like the zero-oxygen atmospheric pressure example above, causes the lungs to work in reverse, and leads to *very* rapid unconsciousness, allowing the diver to skip the symptoms of hypoxia.
Hypoxic conditions are very reliably detected by divers, and very uncomfortable, and eventually panic inducin
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Plausible explaination. Its possible the brain has an "Oh shit, I'm dying right now!" reaction that attempts to wake up the body for a last ditch effort to survive. The problem of course is if the rest of the brain is utterly melted, its not going to succeed. So without sensory input it does what brains seem to do when deprived of input, it hallucinates, dreams. (I'm fairly convinced dreaming is just a signal to noise thing. Neurons adjust input weightings to normalize out signal strengths. The quieter the
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Actually it does - it's a part of the autonomous system. If your O2 saturation gets too low, your brain does a final stab at trying to wake up and get more air. It's why sleep apnea is a problem - the airways get blocked, the brain detects the lack of oxygen and then wakes up and tries to breathe. Of course, to go from sound asleep to wake up with a startle generally o
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So without sensory input it does what brains seem to do when deprived of input, it hallucinates, dreams. (I'm fairly convinced dreaming is just a signal to noise thing. Neurons adjust input weightings to normalize out signal strengths. The quieter the signal, the higher it turns up the input amplitude. Of course basic signal theory says the closer the signal to noise floor is, the more artefacts you get in the data, thus more misfiring = dreams. Somewhat like how if you introduce noise into a neural network trained on imagery you get surrealistic imagery coming out.)
Interesting to combine your theory with the CxG (Construction Grammar) theory of language.
Rather than the brain doing full word-by-word syllable-by-syllable sentence/semantic diagramming, perhaps it is constantly experiencing hundreds/thousands/millions of lifelong-recurrent and recently-primed possible Constructions of meaning all swirling around in there. And "intelligence" is the process by which the brain rapidly cycles through possible permutations of constructs. So the possible reality-Constructions a
That's crazy (Score:1)
Beats most users I've supported then.
It's not impossible (Score:2)
It's merely unlikely. You have to get enough people in that state who then miraculously recover and can tell you what they recall so you can look for the commonalities.
Also, for a while now science has been able to zap a specific part of your brain with a magnetic pulse and give you the "light at the end of the tunnel, friendly face, and sense of peace" feeling many people who have almost died describe. Since this can be deliberately induced, one would like to imagine the people who had it done also had t
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Sounds like a lot of work.
Someone pass the LSD.
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A potential treatment or test (Score:4, Interesting)
Bring the patient to the brink and then restore life support. If the activity is conscious in nature, it may take a few tries to bring them back. If there is no response then they were truly gone.
It may also be possible to determine the chemical storm that brings them back and reproduce that without half killing the patient.
Re:A potential treatment or test (Score:5, Interesting)
Bring the patient to the brink and then restore life support. If the activity is conscious in nature, it may take a few tries to bring them back. If there is no response then they were truly gone.
That's possibly not a terrible idea. I seem to vaguely recall that every so often, someone suddenly wakes up when someone shuts off the ventilator, and if they're actually brain-dead, presumably it can't hurt to try. Then again, if they're only mostly dead, it could just end up being a cruel, horrible way to die over and over again, so maybe not. Hard to say.
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Indeed...
Then again, if they're only mostly dead, it could just end up being a cruel, horrible way to die over and over again, so maybe not. Hard to say.
Whoo-hoo-hoo, look who knows so much. It just so happens that your friend here is only MOSTLY dead. There's a big difference between mostly dead and all dead. Mostly dead is slightly alive. With all dead, well, with all dead there's usually only one thing you can do ... Go through his clothes and look for loose change.“ -- Miracle Max (Princess Bride)
PS: Why doesn’t /. support Unicode still?
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I was thinking the same thing, especially for patients that might otherwise be bodily healthy enough to recover from the process. I suppose the biggest issue is cost, the machines that can perform these sorts of brainwave scans are expensive and exist in only a limited quantity.
So.... (Score:2)
...coma is not what we think - it's something even deeper than sleep used to repair damage to a greater extent than possible during sleep - but the consciousness is still there with an alarm set - until the patient is killed?
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"...they pressure families to turn off life support so that someone else can use the bed"
Interesting that you complain about emphasizing quality over quantity when commenting about the opposite.
Besides, people make decisions, not "modern medicine". "Modern medicine" is not a "they" and doesn't "pressure families" at all.
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My wife is a nurse, used to do end of life care. After the stories she has told me, I updated my directives. If I am in a coma like that, I do not WANT to be resuscitated. Same if my heart is stopped for an extended period of time. Its NOT like the movies where someone wakes up and they are A-OK, or are running a marathon the next day after CPR brought them back after being dead for a while. You are very very likely to end up in a care home for the rest of your life, shitting in your diapers and m
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Agreed, its sad that modern medicine is so focused on quantity and not quality that they pressure families to turn off life support so that someone else can use the bed. https://www.dailysabah.com/tur... [dailysabah.com]
Your argument isn't internally consistent because it ignores the fact that these people would already be well and truly dead if it weren't for modern medicine in the first place, they've just been given a postponement. That is all we can give them, we don't understand the human body well enough to work true miracles. Alas we as a society have decided to allocate a limited budget to medicine, so there is a limited number of beds (usually limited by staffing rather than equipment).
What you have in effect sugg
My laptop too (Score:5, Funny)
Same with my laptop. If left in sleep mode and battery runs (slowly) out, it wakes up, and it shuts down.
Anyone get a Murder-Mystery vibe reading that? (Score:2)
So who was it? The orderly, the zealous nurse, the attending physician, the family member of one of the patients who always visits, the documentary producer, or was it the representative of the giant research company? Gasp, or was it a combination of them?
Every Time Columbo Asked One More Thing | Season 1 | Columbo
https://youtu.be/sB-jlomZhHU [youtu.be]
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Notice the bad faith "journalism"? (Score:1)
First, start with a provacative comment, then suggest scientists have confirmed something they have not.... ..."
"Some recall bright lights at the end of a tunnel, feeling the presence of loved ones or floating above their body after a near-death experience. Now, scientists say they have
Then to cover your own ass...
"Scientists said it was impossible to know exactly what the brain activity might correspond to as a subjective experience."
Next thing, con men like William Lane Craig will intentionally misreprese
n=4 "study" (Score:1)
Final sync before umount/shutdown (Score:2)
If you're still connected to the Matrix you need to do a final sync before umount/shutdown. The 2 that didn't show activity probably weren't connected anymore.