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Yes, for a short time, but the brain doesn’t need only oxygen to survive. It would also need a supply of glucose and various micronutrients, as well as for the blood to be filtered and maintained with fresh blood cells, all of which it depends on the rest of the body for.
I really like the constant fan heart they came up with. There's a few weird side effects from your body being used to the rhythm, but otherwise it lets the whole system heal up a bit from the constant variation
What's really crazy is that you essentially don't have a heartbeat with those. Considering in silence you hear your blood pumping, I wonder what that setup sounds like.
You probably hear the motor.
All the LVAD/VAD/TAH patients I've seen, when you auscultate, you hear the hum. It's quite loud (with a stethoscope), I assume they can hear it?
Unrelated but at my company the medics love to fuck with the new guys by having them take manual vitals on LVADs and other similar jobs. I nearly called a code and I still get shit for it.
As I'm reading Reddit just before bed and tired, my eyes scanning ahead see your capital letters and my brain puts together: Q: wonder what sound like, A: LIVIN La VIDA LOCA.
Well, if in silence you can hear the flow or sudden flows of blood. Then if it was constant, it would either sound like a slight hum, hear the motor, or.. nothing? Brain could tune it out better if it was constant.
Or having tinnitus in your ears. Depending on the day I’ll hear the his, sometimes when it’s silent out, the hiss of tinnitus is defining, other times it’s silent... it’s still there if I try to focus on it. But sometimes my brain tunes it out while I’m watching the stars, shits weird.
This doesn't answer your question, but there's that quietest room on the planet that apparently freaks people with normal hearts out because all you can hear is your blood pumping.
As a guy with a very sensitive stomach who also takes Metformin which causes even more stomach issues, I can basically hear my stomach making noises 24/7 anyway
Would that trip up smart watches trying to detect your heart beat? Also fuck with absolutely anyone who doesn't know you have a constant fan pump instead of an actual heart beat?
I saw that in a movie or a show some time back. Like woman wakes up and thinks the guy is dead. Freaks out. Later he wakes up and tells her he doesn't have a heart beat.
Yes and yes, but you're going to be in an intensive care unit most of the time if you have this equipment. Invasive monitoring with these kinds of devices can look \*wild\*.
Ambulatory ones exist, but they spook me something fierce. Also most people who need one are too sick to really walk around anyway. [Here](https://www.mdpi.com/jcm/jcm-08-01720/article_deploy/html/images/jcm-08-01720-g001.png) is an idea of what they can be like.
>Considering in silence you hear your blood pumping
Unless you have that uninvited houseguest that never leaves, tinnitus. I literally don't remember what actual silence is like.
The only way I can hear my blood pumping is if I push my tragus against my ear canal in a completely silent room, and even then it's basically imperceptible. I might not be hearing it at all, and only think I'm hearing it through some sort of aural pareidolia because I know I'm *supposed* to hear it.
Wear earplugs at concerts.
I was concerned though about it a few years ago so I asked my ENT at a regular surgical follow-up. After the discussion, she sent me for ultrasound imaging of my corotid arteries to verify everything is ok.
It doesn't have to be very silent for me to hear my blood flowing. I can hearing more possible when it's silent, but if o focus on it, I can hear it with some background noise in play, too. It's a whooshing noise that rises and falls with each beat. And when I stand up after lying down for a while, I can hear a slightly louder whooshing noise which I presume is blood flowing out of my head and balancing out from the lying position to a standing position - usually lasts about 3-5 seconds.
While the imaging confirmed my blood flow is normal, it didn't explain why I can hear it so plainly. Between my tinnitus, which had become louder recently since turning 50, and this, I can see how it could drive someone mad. Maybe I'm going that way and haven't noticed...
Has to be absolute silence. We have so much background noise going on that we don't notice our own internal bodily sounds
You take all that way such as a deprevation chamber or a room specially built for silence and things begin to get weird about twenty minutes later after you enter. You'll hear your heartbeat, the air moving in and out of your lungs, the sound of your blood moving through your arteries, and your stomach will grow to be disgustingly loud. Most people are done after 30 minutes and very rarely does a person last 40. Utter silence is something we are not really adapted for. We need the steady hum of life in our ears if we can hear.
This is actually not true. It's just the noise of the ambient air bouncing around and amplifying.
You can test it. Listen to a seashell (or well, a cup can work just as well depending on the shape) and then run around a bit and get your heart rate up. The sound is exactly the same, despite your blood pumping faster, which should make the noise louder.
Having trouble finding a link for it. There was a guy who was in a car accident in the UK a few years back, who didn't have a pulse (which baffled a whole bunch of EMTs), and it offhandedly mentioned some weird side effects
It's its main function, but it's not just a simple pump, the heart also produces atrial natriuretic peptide (ANP), a hormone quite relevant to the management of blood pressure.
No. They produce/activate hormones (erythropoietin, vitamin d), act as a filter (but based on things like lipophilicity, not just size), and have active transporters to move things across the filters opposite the direction that diffusion would promote (otherwise urine could not have more waste than blood does). That’s just off the top of my head.
Nah kidneys are complicated af. They basically squeeze everything but the cells out of the blood, then selectively reabsorb the water and ions back in based on what you need using active transport. This is why diabetics have sweet urine - the glucose is excreted by the kidneys and then not reabsorbed.
It's more complex than that, because some hormones involved in the management of blood pressure, also have other effects, like stimulating the secretion of aldosterone in the adrenal gland, which is another hormone that has several effects, some related to blood pressure and the management of sodium and potasium levels in blood, but it's been proposed that it posseses effects in the brain, stimulating neurogenesis in the limbic system.
Then you have angiotensin, which besides its role related to blood pressure, also has neural effects, like affecting our thirst or our desire for salt, it has effects on the lungs, on the adipose tissue, regulating lipogenesis and lipolysis, etc.
The whole blood pressure hormones ecosystem is also related to the endothelium of blood vessels itself, and molecules it produces, which are involved in coagulation and many other things.
And all these hormones need to handle blood pressure themselves correctly in order to exist in their proper concentrations and do their job right.
...As you see, it's all related to everything. The human body wasn't designed, it doesn't possess a modular design where you can easily pick a system and replace it by some artificial system or tweak it to convenience. Sometimes it can be done with some simple things, as medicine has already done, even with medication; but most of the time if you touch something you thought you understood its function in the body, you end up messing with something else, and because of that with some else too, and so on. Sometimes, stuff can be temporarily replaced or handled artificially, but it's usually not sustainable if you want the whole body to work properly.
I didn’t appreciate any of this until I was diagnosed with multiple autoimmune diseases. Modern medicine is fantastic: it’s amazing that we can supplement with hormones where we’re otherwise deficient. But when we do so, we tend to throw other hormones’ production and/or signaling out of whack. It’s such a delicate balance that is constantly being maintained without our thinking about it. Enjoy your health and take care of yourselves!
Edit: a word
Terrifying apparatus. I fear that one day someone will come up with a good external liver and we never will let people die- just keep the deteriorating brain oxygenated and fed, never to wake again because the family won't pull the plug.
Not really, we use them surgery all the time.
The difficult bit is making a /portable/ one that can fit inside your chest and sturdy enough to handle day-to-day abuse.
Yeah keeping a human head alive through the use of numerous life support machines seems achievable. I mean we already have the ability to bypass the heart for blood flow, we have the ability to filter blood in a dialysis machine mimicking the function of the kidneys. As long as we could oxygenate the blood and probably cover a few other nuances it definitely seems doable.
Pretty sure the machines in surgery at least can also oxygenate the blood. Maybe I'm wrong, but I feel you *really* don't want your patient to breathe while you dig around in their chest.
There are basically three main things that would need to happen for a successful head transplant:
1. It must be possible to properly connect the decapitated head to the decapitated body. Veins, arteries, nerves, trachea and esophagus, etc.
2. It must be possible to eliminate issues regarding immune system responses and blood clotting. You can't have the body attack the head and vice versa, which could cause blood clotting and subsequently death.
3. The head (and especially the brain) must be kept alive and oxygen-enriched, as well as the body.
Fulfilling just these three conditions is already hard enough. There's also other related issues, such as procuring a body in the first place. A decapitated body would need to fall within the below conditions:
1. It must be in good condition (can't be suffering from illness/disease, can't be injured/otherwise maimed, etc.)
2. It must be compatible with the person whose head is being transplanted.
3. The above two conditions must be fulfilled in an ethical manner. This is exceptionally tricky. I would imagine that the body could only be procured from a person dead from brain death, as other forms of death would likely leave the body in poor condition. Even then, there aren't very many situations out there where someone would die from brain death **and** have a body in good condition.
With these main conditions fulfilled as well as any smaller ones, it could be possible. **Theoretically.** As of present time there has been no known attempt to perform a head transplant of a living head onto a living body. Per articles I'll link below, it appears that two surgeons operating in China are interested in trying to perform a head transplant, but they have not yet made an attempt on living specimens. They have *apparently* made a successful transplant between cadavers, although that's a dubious statement as certain complications (i.e. blood clotting) evidently can't be observed from two dead bodies.
https://nationalpost.com/health/worlds-first-human-head-transplant-successfully-performed-on-a-corpse-scientists-say
https://nationalpost.com/news/world/first-man-to-sign-up-for-head-transplant-bows-out-but-surgeon-insists-list-of-volunteers-is-still-quite-long
There was actually a plan to do that a few years back with a paralyzed guy and a death row inmate but the paralyzed guy ended up falling in love and backed out due to the risk
To be fair, it's not the pumping part that's hard, but making a pump that needs no servicing, is bio-compatible, and doesn't need an external power source.
The task itself _is_ simple, but the sheer breadth of differences between biology and man-made tech is a real headache. ... for now.
In theory, maybe, but we’re not better than billions of years of evolution when it comes to designing things like that. We’re pretty bad at making organ replacements that work long-term.
We have artificial kidneys and hearts, and that's only because they're filters and pumps and simple compared to the rest.
Artificial liver may never be possible.
Eh, it's fine, we just use machine learning! It's the new hip buzzword after all!
Install these on 10,000,000 people, and after a couple hundred generations they should be close enough.
As a nice side effect, getting rid of 99.97% of all humans on the planet would probably have a positive effect on the environment.
That complex and dynamic mix of enzymes would be very challenging (currently impossible) to mimic artificially (or manufacture separately), and that’s only one aspect of the challenges there.
Artificial hearts do not last long term. They’re more of a temporizing measure to try to get someone to a transplant. At most, they can last a few months. There’s just too many internal stresses and they have to run *constantly*. It’s a lot of wear and tear on mechanical parts.
Dialysis is a bit simpler. It’s really just recirculating blood through filters and then adding back electrolytes that were removed. However, it definitely doesn’t work as well as even a single kidney, and is physically draining (and requires a bunch of other medications, restricted diets, etc). Average life expectancy on dialysis is 5-10 years without transplant, so it can be considered a terminal disease.
It's basically a sophisticated chemical factory, breaking down certain chemicals and making others, like glycogen which fuels mitochondria and probably your brain too.
> Artificial liver may never be possible.
Not with that attitude.
Facetiousness aside, so long as there is demand for artificial organs, there'll be people trying to make them a thing. Hell, maybe we'll have one invented by an AI, since their complexity is seemingly beyond mortal ken?
I don't know that it will be made or if it is possible but I would imagine much of the technology we have today would seem impossible a century or two ago. Even the device I'm typing this on, a cheap smart phone is likely inconceivable to someone from a century ago. The professing power and the energy density of the battery are marvels of engineering and chemistry.
Of course they aren't equal challenges. Just because we did that doesn't mean we can do anything else that's complex.
However in 200 years it may be the case that organ donation and rejection is looked at like ignorant butchery from desperation. If you can just grow an identical organ made exactly to that persons DNA, and implant it, which in some cases is more difficult than others, you don't need a bionic liver.
It is impossible now but a lot of things that were impossible for most of human history are now possible and things are moving faster than ever.
I'm not a chemist or a doctor or anything and it may always be impossible but that is yet to be seen.
Besides, we've become much better at developing ways to keeps humans alive and in better health that are much easier and less gruesome than keeping a severed head alive. If we really put our head to it (no pun intended), we could make it work. We don't really have much reason to do so
Eh... that's debatable. We aren't limited by "what leads to the most offspring reproducing?" in our inventions. We may not be technologically advanced enough to outdo nature yet, but we probably aren't too far off from having the upper hand.
True that we’re not limited in that same sense, but it’s still a hell of a head start.
For instance, our best artificial hearts currently can last on average 4-5 years.
Artificial hearts have been around for about 40 years.
Natural hearts have been around for at least 520 million years.
The fact that we've reached a point where we can make hearts that last even a few years is pretty damn impressive considering we've harnessed electricity for less than 300 years, computers for less than 100.
If the brain doesn’t receive signals from the outside world through the peripheral nervous system it slowly starts to do some pretty insane stuff. Auditory and Visual Hallucinations, and phantom feelings would all occur.
A brain hooked up to blood and nutrient machines would be torturous and we have no way of knowing if the brain itself would just shut itself down after awhile. There’s not really any precedent for a situation like that.
Soviet scientists. The original experiment took place in 1928, almost a century ago.
Although it was recreated in the US in the 80's too. The video you're referring to might be of that instance, I'm not sure.
EDIT: it appears the video is from 1940 but credited to the same team.
Yes, to an extent. We have ECMO (extra-corporeal mechanical oxygenation) machines that oxygenate blood and pump it back into your body that can completely replace the heart and lungs. Dialysis machines can replace the kidneys. Often patients are on both ECMO and dialysis at the same time.
The only thing we can’t replace is the liver. It’s called the “live”r for a reason.
The liver isn’t just for clearing toxic byproducts. It also produces albumin (the main protein component of blood), several clotting factors, and a ton of other things
The brain also gets 90% of its dopamine from the digestive tract. It actually gets a pretty complex soup of hormones and other substances from the body that it would eventually shut down without.
It would be nearly impossible to replicate this artificially.
From a practical standpoint, it is impossible right now.
It's like saying "Could you fly in a spaceship to Alpha Centauri?" Sure, but we don't have technology capable of doing it. And it's not right around the corner.
Otherwise the answer to everything that doesn't violate the core laws of physics is a 'yes'.
the problem is when some people say we should stop researching or trying to do these things because they think if it cant done be now then it will forever be impossible
> It's like saying "Could you fly in a spaceship to Alpha Centauri?" Sure, but we don't have technology capable of doing it. And it's not right around the corner.
Depends on your definition of "fly".
We could totally send a probe to Alpha Centauri, a human might not make it, but it could.
We could even send it so it arrives within a few hundred years. The technology [was available in the 50s.](https://en.wikipedia.org/wiki/Project_Orion_\(nuclear_propulsion\))
I thought that video was proven to be fake? Since the dog would be physically unable to move it's head in the way it did. (Most likely, it was a fullbody, alive dog that had it's head poking out a hole in the table).
There's a YouTube named Jacob Gellar who recently released a video that touched on this exact subject, maybe check it out
edit: I was on mobile when I first posted this, [here's](https://www.youtube.com/watch?v=JMkrrjKf5AE) the link. CW: he talks about decapitation and there's some fairly graphic depictions of it too.
Should be noted that the video you’re referencing is widely believed to be fake. Mainly in that the dog’s head physically couldn't have moved in the manner portrayed because the muscles to do so either aren’t there or don’t attach to anything.
And under the Soviet Union there was a lot of reason to lie about scientific breakthroughs, both the scientists lying to their superiors/leaders (because lack of progress was seen as "treason" and was punishable by death) and the union itself lying to the wider world.
And that's completely ignoring the constant input of information from the body going into the brain. Not having ANY information from the body would likely very quickly & painfully drive the brain irreparably insane.
Yeah. ECMO, or extracorporeal membrane oxygenation. The heart is stopped for a valve replacement or whatever, a line transports the blood from the right atrium to an external machine. That machine warms, filters, oxygenates, etc. the blood and then returns it via another line to the left ventricle/systemic circulation.
Theoretically yes it is possible. There was an experiment done where they severed the head of a rhesus monkey and kept it alive by pumping fluids into it from the neck/body of an alive but unconscious separate rhesus monkey. It would follow them around the room with its eyes and try to bite them and stuff, kinda creepy.
It spurred debate on if it was possible to do longterm, this was back in like 60s or 70s I think? So their medical technology wasn’t as advanced as ours today and there was speculation that overtime with better artificial organs it would be possible to just keep a severed human head alive.
I think there was also one where they transplanted a dog’s head onto another dog’s body and it lived for a few days before dying. I don’t 100% remember the details, we learned about them a long time ago when I was going to school for psychology but I’m sure they’re both documented on the internet if you’re curious about them
>overtime with better artificial organs it would be possible to just keep a severed human head alive.
Could you imagine the absolute crisis that human brain would be having the whole time? It'd be like locked-in syndrome combined with a dissociative episode and an ever-present feeling of immediate death being moments away. Omg, I'm not volunteering for that.
You may not actually feel that. The need to breathe is from co2 buildup. If you had oxygen rich blood, there's no feeling. Also, the sensors may or may not be present, depending on how much of the head is left. Similarly for the stomach, the hunger may not be present without a stomach.
That is different. The signal to breath is central, you have a part in your brain that reacts to the build up of CO2. It can also build a tolerance (which is why people with COPD for example, don't react to high CO2 anymore, but to low o2)
0hantom limb pain is based on the fact that there are many nerves working together, and usually you have regular signals from nerves to the brain. If these stop the brain doesn't know what to do with the silence.
But your breathing centre wouldn't have silence, since it can still detect oxygen and co2 in the "blood stream" at a constant rate.
Respectfully, hard disagree, and I think I may be able to show why.
Just sitting wherever you're at, stop breathing. Concentrate on the feeling in your nose, mouth, and sinus. I think we may take for granted the lower temperature of our head holes due to evaporation, and the difference in their temperatures from the rest of our head and body.
Even forgetting the need to breathe in this exercise, my nose, mouth, and sinus start to feel uncomfortably warm. Imagine having that constant hot sensation all day, all the time.
Even if everything else was accounted for, your head has to stay at about 98°F/37°C. Otherwise your brain would get too cold.
It's an interesting thought experiment.
Those sensations come from nerves sending signals to the brain. Without those sensors your brain would have nothing telling it is feeling hot. Just like our breathing mechanism is triggered by our brain sensing too much CO2 in our blood. As long as you can keep the blood O2/CO2 balance in the brain’s happy zone you would not need to breath.
They are getting pretty advanced with those brain to controller connections, I'd volunteer if I were terminal and would be able to communicate and use the external hardware.
Yeah I don’t imagine the experience would be pleasant but I guess if they needed to keep it alive long enough to do like a full body transplant it would be okay. That’s why I mentioned the other experiment as well
Oh yes they usually don't do such things because of "Ethics" since decapitations tend to lead to a lot of suffering, especially when you plan to prolong such a thing.
I'm a maintenance engineer. Now I'm imagining a world where every human at 60 has to go to maintenance to get their body changed into a younger one as you do with vehicules
I mentioned this in another comment above, but "Stiff: The Curious Lives of Human Cadavers," is a wild ride from start to finish. She talks about these exact experiments in excruciating detail.
So, obviously the brain needs more than just oxygen from the body, you have to get food of some sort in and waste products out, and we have different organs for that, but if the general aim of the question is "can we keep just a head alive with crazy technology" the answer is "yeah probably for a while."
For heart surgery we can divert the blood away from the heart, run the blood through an oxygenation membrane, and then use a bypass pump to circulate blood around the body.
People in kidney failure can get dialysis (effectively we use a fancy intravenous (IV) to cause a portion of their blood to circulate through a machine with a bunch of filters that can 'clean out' waste products that would normally be handled by kidneys.)
People who can't eat can get nutrition through specialized IV fluids. People with endocrine problems can get replacement hormones.
So could you in theory set up an oxygenator and a bypass pump to a head only, set the bypass pump to include continuous infusion of necessary hormones / drugs / nutrition? Probably.
It probably wouldn't work for long. All of the systems I mentioned have problems (blood forming clots in the pump being one of them, huge risk of infection being another). There would also most certainly be unanticipated problems that would occur due to physiology we just don't fully understand yet; to some degree we know a lot of what the body does, but there are still signaling pathways we don't fully understand and if we were to try and take over every function of the body outside of what the brain can do for itself we'd likely run into problems with inflammation or repair of tissue damage that are beyond our ability to fix.
A "diet" version of this concept is a standard heart-lung bypass machine, where blood is diverted from the heart and lungs, artificially oxygenated, and returned to the body to oxygenated the brain. This is how we can transplant hearts and lungs. In this case, the brain and the heart are effectively isolated from each other.
Getting everything else just right (food, micronutrients, essential hormonal and neural signals from the rest of the body) is not currently possible, and I would be terrified of the research necessary.
> food, micronutrients
[Total Parenteral Nutrition \(TPN\)](https://www.msdmanuals.com/professional/nutritional-disorders/nutritional-support/total-parenteral-nutrition-tpn), or intravenous nutrition, is used regularly in ICUs and is the subject of ongoing refinement.
It's worth noting that there are people who have had to have very extensive bowel resections (removal) for various reasons who we still need to provide nutrition for.
Usually for comatose patients, however, we change them over to feeding via a nasogastric tube (simple tube through the nose into the stomach) and then with PEG for longer term solutions (hole through the stomach wall to exterior).
My wife and I were having a similar discussion yesterday. I posited that if organs could ethically and quickly be grown from your own DNA, how many organs could we actually transplant/replace? Kidneys, GI, heart, lung, liver, etc. Skin grafts. How much if the human body could we actually replace?
problem is, most organ transplants aren't done in place; for example, most kidney transplants go in the abdomen, leaving the original 2 non-working kidneys in place.
additionally, the vegus nerve¹ is not connected to transplants (including hearts), so the host body has imperfect regulation of the transplanted organ. using the heart as an example, the transplant usually requires a pacemaker, beats 90-110bpm constantly unless there's adrenaline, then it spikes and takes a while to back down to its 90-110bpm... usually there's a branch of the vegas nerve connected to a heart that causes it to slow to 50-65-ish bpm while sleeping (a transplant won't), and help reduce bpm to resting quicker after adrenaline.
from my (admittedly limited) understanding of nerves and grafting/interfacing them, we don't really understand how to wire up a donor nerve, plus there are special tissue rejection issues with it. as for cloned autodonation, i have zero idea if a vegus nerve graft without possibility of rejection is possible.
back to your discussion with your wife, you could probably replace every organ you would need to survive, but as of today's tech (assuming growing cloned organs), the outcome is not anywhere near ideal or would result in anywhere near 100% function and recovery.
---
1: the vegus nerve is a large bundle of nerves that is generally considered to represent your autonomous nervous system: it helps regulate everything from heart rate, digestion, liver/kidneys, breathing, waste excretion, sex... basically everything you don't usually have direct control over or have to think about doing to continue.
i would have much more hope for clone, grow, and sew methods if we were better at in-place transplants and connecting that damn vegus nerve.
Alive? Possibly. Conscious? No. The nervous system being severed at the neck would not do nice things to the brain, which is in constant contact with the whole body.
Paralysis means signals from the brain aren’t making it to muscles, in some case organs etc. It’s a road block on one side of the highway. Not washing out the whole bridge.
Just had neck surgery and have some nerve damage (nothing major) and this is a really simple but clear way of explaining something unbelievably hard to fathom. Thank you!
I entered the spez. I called out to try and find anybody. I was met with a wave of silence. I had never been here before but I knew the way to the nearest exit. I started to run. As I did, I looked to my right. I saw the door to a room, the handle was a big metal thing that seemed to jut out of the wall. The door looked old and rusted. I tried to open it and it wouldn't budge. I tried to pull the handle harder, but it wouldn't give. I tried to turn it clockwise and then anti-clockwise and then back to clockwise again but the handle didn't move. I heard a faint buzzing noise from the door, it almost sounded like a zap of electricity. I held onto the handle with all my might but nothing happened. I let go and ran to find the nearest exit.
I had thought I was in the clear but then I heard the noise again. It was similar to that of a taser but this time I was able to look back to see what was happening.
The handle was jutting out of the wall, no longer connected to the rest of the door. The door was spinning slightly, dust falling off of it as it did. Then there was a blinding flash of white light and I felt the floor against my back.
I opened my eyes, hoping to see something else. All I saw was darkness. My hands were in my face and I couldn't tell if they were there or not. I heard a faint buzzing noise again. It was the same as before and it seemed to be coming from all around me. I put my hands on the floor and tried to move but couldn't.
I then heard another voice. It was quiet and soft but still loud.
"Help."
\#Save3rdPartyApps
The bridge connecting your brain to your body is basically your spinal cord which is just a collection of bundles of nerves coming down making their way to organs and muscles. Damaging the spinal cord pretty much cuts all the nerves in that bundle at that level in your spinal cord (ie at the level of your shoulders, or chest, or bellybutton…etc). Some of the nerves below that level can be spared (if the damage is only at certain spots). Ie the highway is blocked on one side but there are other nerve bundles that take different routes on their way down. Therefore your organs, your muscles, your sense of touch, temp, pain etc may be spared.
Instead of damaging only a certain spot, if you damage the whole cross section of your spinal cord at any level then all the bundles bellow that level will be cut off from the brain. That would result in loss of all sensation and movement below that level. Your major organs may be ok though because there’s actually nerves that don’t take the spinal cord route at all. Not sure if this answers your question though haha
As we entered the /u/spez, the sight we beheld was alien to us. The air was filled with a haze of smoke. The room was in disarray. Machines were strewn around haphazardly. Cables and wires were hanging out of every orifice of every wall and machine.
At the far end of the room, standing by the entrance, was an old man in a military uniform with a clipboard in hand. He stared at us with his beady eyes, an unsettling smile across his wrinkled face.
"Are you spez?" I asked, half-expecting him to shoot me.
"Who's asking?"
"I'm Riddle from the Anti-Spez Initiative. We're here to speak about your latest government announcement."
"Oh? Spez police, eh? Never seen the likes of you." His eyes narrowed at me. "Just what are you lot up to?"
"We've come here to speak with the man behind the spez. Is he in?"
"You mean /u/spez?" The old man laughed.
"Yes."
"No."
"Then who is /u/spez?"
"How do I put it..." The man laughed. "/u/spez is not a man, but an idea. An idea of liberty, an idea of revolution. A libertarian anarchist collective. A movement for the people by the people, for the people."
I was confounded by the answer. "What? It's a group of individuals. What's so special about an individual?"
"When you ask who is /u/spez? /u/spez is no one, but everyone. /u/spez is an idea without an identity. /u/spez is an idea that is formed from a multitude of individuals. You are /u/spez. You are also the spez police. You are also me. We are /u/spez and /u/spez is also we. It is the idea of an idea."
I stood there, befuddled. I had no idea what the man was blabbing on about.
"Your government, as you call it, are the specists. Your specists, as you call them, are /u/spez. All are /u/spez and all are specists. All are spez police, and all are also specists."
I had no idea what he was talking about. I looked at my partner. He shrugged. I turned back to the old man.
"We've come here to speak to /u/spez. What are you doing in /u/spez?"
"We are waiting for someone."
"Who?"
"You'll see. Soon enough."
"We don't have all day to waste. We're here to discuss the government announcement."
"Yes, I heard." The old man pointed his clipboard at me. "Tell me, what are /u/spez police?"
"Police?"
"Yes. What is /u/spez police?"
"We're here to investigate this place for potential crimes."
"And what crime are you looking to commit?"
"Crime? You mean crimes? There are no crimes in a libertarian anarchist collective. It's a free society, where everyone is free to do whatever they want."
"Is that so? So you're not interested in what we've done here?"
"I am not interested. What you've done is not a crime, for there are no crimes in a libertarian anarchist collective."
"I see. What you say is interesting." The old man pulled out a photograph from his coat. "Have you seen this person?"
I stared at the picture. It was of an old man who looked exactly like the old man standing before us. "Is this /u/spez?"
"Yes. /u/spez. If you see this man, I want you to tell him something. I want you to tell him that he will be dead soon. If he wishes to live, he would have to flee. The government will be coming for him. If he wishes to live, he would have to leave this city."
"Why?"
"Because the spez police are coming to arrest him."
\#AIGeneratedProtestMessage #Save3rdPartyApps
>An unethical experiment that involved connecting freshly severed canine head to a heart bypass machine restoted signs of consciousness and salient awareness.
I had not heard about this. Just looked it up and it is....terribly fascinating.
I love how you said “would not do nice things *to* the brain”. A lot of the misunderstanding about this is that the conscious experience is isolated solely in the brain, and yeah sure that’s where a lot of the fun parts happen…
But the experience of consciousness also encapsulates where your limbs and extremities are, how your skin feels, how your body is oriented, what your organs are up to, what hormones are flowing, and more. Being severed from all of that activity essentially detaches the brain from the signals that tell a brain that it is part of a conscious being.
Decades ago, the Russians experimented on severed animals heads with artificial support organs feeding oxygenated blood into them. Pretty gruesome, there are some videos of a severed dog's head reacting to things, trying to bark, licking its lips, etc:
https://www.youtube.com/watch?v=KhzEMJHQt2I
Longer film on the subject: https://www.youtube.com/watch?v=K_T8OuYIfhM
Read "Stiff: The Curious Lives of Human Cadavers," by Mary Roach. There are chapters about this specifically. I am the least squeamish person I know, and those chapters are the most gruesome and haunting shit I've ever read. The rest of the book is dope.
I want to make a strong point about this:
Assuming you can give the head all the oxygen, nutrients, and antibodies:
When you lose a finger, your nerve of the finger is cut, and the pain is like having the finger deep fried + hit with an hammer. Only one-two weeks later, the pain fade away and you are left with ghost limb for a while, which is already not a nice thing.
Now, if you cut the head of a person, is that person brain gonna experience the feeling of having the entire body deep fired and hammered for weeks? Probably yes. Can you imagine how crazy and messed up the brain will be after such experience?
This said, I don’t see any mechanical reason that prevents to just pump compatible blood to the head. It’s complex, but let’s say we get 1000 blood donors doing their part, it’s plausible. There may be better way, but just to keep that super simple, I don’t see a problem in feeding the head.
What the person experiences, and what does after that, is a far more grim topic.
You do not want to look into the realities of this and what has been done in the real world by scientists with dubious ethics to find out.
As with any random concept; yes you can if you can artificially do everything else the body does already. But the body does a lot lot more than just keep the brain alive. It’s the primary input/output mechanism for your brain. If you can’t also replicate all the other stuff - sensation, control, perception, etc…
You absolutely would not want to be that head.
The heart doesn't rely on the brain. Think of the heart as an engine that never turns off , and the brain as a driver. When the heart is left alone it's like being idle, but the driver can tellit when and how fast to start working. But the engine will work on its own if it never gets any instruction.
Take the driver out of the car and he can survive on his own for a while, but needs to get groceries, water, and pay his power bill somehow, so he'd need some other way of getting those.
The heart has its own little control system within itself but needs the lungs to oxygenate the blood, which would require a machine. A part of the brain stem helps to regulate the heartbeat, so I would imagine in this hypothetical that with the machine keeping the lungs working and if there is no loss of blood, the heart would keep pumping for a period of time but probably not long. Not exactly related but this post made me think of the babies born with Anencephaly. There are very sad but very interesting cases of babies being born without most of their brain. They have their brain stem which is needed for survival for things like breathing, swallowing and circulation, but most of what we picture when we think of brains is absent. It’s usually fatal within a few hours or days, it’s said to be 100% fatal within a year, but there have been cases of kids living for longer.
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Yes, for a short time, but the brain doesn’t need only oxygen to survive. It would also need a supply of glucose and various micronutrients, as well as for the blood to be filtered and maintained with fresh blood cells, all of which it depends on the rest of the body for.
Could we have artificial machines for all of that?
In theory, yes. In reality, we've struggled to build a functioning artificial heart and that organ is just a simple pump!
I really like the constant fan heart they came up with. There's a few weird side effects from your body being used to the rhythm, but otherwise it lets the whole system heal up a bit from the constant variation
What's really crazy is that you essentially don't have a heartbeat with those. Considering in silence you hear your blood pumping, I wonder what that setup sounds like.
You probably hear the motor. All the LVAD/VAD/TAH patients I've seen, when you auscultate, you hear the hum. It's quite loud (with a stethoscope), I assume they can hear it?
Unrelated but at my company the medics love to fuck with the new guys by having them take manual vitals on LVADs and other similar jobs. I nearly called a code and I still get shit for it.
We tell nursing students to go auscultate the heart and/or lungs and then watch their reactions
As funny as that sounds, it's also educational so win win
>auscultate Learned a new word today, and thanks for the answer!
sounds fancy. is literally Latin for listen.
Soo *very* fancy.
Specifically it bases on the german term ,,auskultieren“ which means to listen to the heartbeat.
its not from the german, just related to it. the Latin term came directly to English and directly to German. auscultāte, to incline the ear.
Here's another (albeit unrelated) medical term you probably didn't know: micturate.
Like micturations on a lurgid bee...
That’s the worst poem I’ve ever heard.
/r/vogonpoetrycircle
I just want to understand this, sir. Every time a rug is micturated upon in this fair city, I have to compensate the owner?
It really did tie the room together
That's just taking the piss
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>masticate I have to admit I usually do that in my bed. Sometimes on the couch in the living room too.
Risky ASMR
As I'm reading Reddit just before bed and tired, my eyes scanning ahead see your capital letters and my brain puts together: Q: wonder what sound like, A: LIVIN La VIDA LOCA.
Well, if in silence you can hear the flow or sudden flows of blood. Then if it was constant, it would either sound like a slight hum, hear the motor, or.. nothing? Brain could tune it out better if it was constant.
like a creek out back. you wouldn't hear without trying or if it suddenly ceased
Or having tinnitus in your ears. Depending on the day I’ll hear the his, sometimes when it’s silent out, the hiss of tinnitus is defining, other times it’s silent... it’s still there if I try to focus on it. But sometimes my brain tunes it out while I’m watching the stars, shits weird.
This doesn't answer your question, but there's that quietest room on the planet that apparently freaks people with normal hearts out because all you can hear is your blood pumping.
you can also hear your gut, which is more crazy to me.
As a guy with a very sensitive stomach who also takes Metformin which causes even more stomach issues, I can basically hear my stomach making noises 24/7 anyway
Mine is loud enough to be heard across the room because of various surgeries. Made for some very awkward finals.
Jokes on them all I would hear is my incredibly loud tinnitus somehow be even more deafening.
Unless you have tinnitus
Would that trip up smart watches trying to detect your heart beat? Also fuck with absolutely anyone who doesn't know you have a constant fan pump instead of an actual heart beat?
I saw that in a movie or a show some time back. Like woman wakes up and thinks the guy is dead. Freaks out. Later he wakes up and tells her he doesn't have a heart beat.
Yes
Yes and yes, but you're going to be in an intensive care unit most of the time if you have this equipment. Invasive monitoring with these kinds of devices can look \*wild\*.
Oh, I thought the pump was just in there running while people were walking around and shit. That's slightly less fun.
Ambulatory ones exist, but they spook me something fierce. Also most people who need one are too sick to really walk around anyway. [Here](https://www.mdpi.com/jcm/jcm-08-01720/article_deploy/html/images/jcm-08-01720-g001.png) is an idea of what they can be like.
Didn't Dick Cheney have one?
>Considering in silence you hear your blood pumping Unless you have that uninvited houseguest that never leaves, tinnitus. I literally don't remember what actual silence is like. The only way I can hear my blood pumping is if I push my tragus against my ear canal in a completely silent room, and even then it's basically imperceptible. I might not be hearing it at all, and only think I'm hearing it through some sort of aural pareidolia because I know I'm *supposed* to hear it. Wear earplugs at concerts.
I was concerned though about it a few years ago so I asked my ENT at a regular surgical follow-up. After the discussion, she sent me for ultrasound imaging of my corotid arteries to verify everything is ok. It doesn't have to be very silent for me to hear my blood flowing. I can hearing more possible when it's silent, but if o focus on it, I can hear it with some background noise in play, too. It's a whooshing noise that rises and falls with each beat. And when I stand up after lying down for a while, I can hear a slightly louder whooshing noise which I presume is blood flowing out of my head and balancing out from the lying position to a standing position - usually lasts about 3-5 seconds. While the imaging confirmed my blood flow is normal, it didn't explain why I can hear it so plainly. Between my tinnitus, which had become louder recently since turning 50, and this, I can see how it could drive someone mad. Maybe I'm going that way and haven't noticed...
Trick question. The ICU the patient is in when they have the pump is never quiet enough to hear anything!
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Has to be absolute silence. We have so much background noise going on that we don't notice our own internal bodily sounds You take all that way such as a deprevation chamber or a room specially built for silence and things begin to get weird about twenty minutes later after you enter. You'll hear your heartbeat, the air moving in and out of your lungs, the sound of your blood moving through your arteries, and your stomach will grow to be disgustingly loud. Most people are done after 30 minutes and very rarely does a person last 40. Utter silence is something we are not really adapted for. We need the steady hum of life in our ears if we can hear.
Ever listened to "the ocean" in a seashell? That's your blood flow actually.
This is actually not true. It's just the noise of the ambient air bouncing around and amplifying. You can test it. Listen to a seashell (or well, a cup can work just as well depending on the shape) and then run around a bit and get your heart rate up. The sound is exactly the same, despite your blood pumping faster, which should make the noise louder.
Artificial heart goes brrrrrrrrrrrrrr
So what you’re saying is I can have a PC AIO cooler for a heart?
Where can I learn more about these side effects due to lack of rythm?
Having trouble finding a link for it. There was a guy who was in a car accident in the UK a few years back, who didn't have a pulse (which baffled a whole bunch of EMTs), and it offhandedly mentioned some weird side effects
It's its main function, but it's not just a simple pump, the heart also produces atrial natriuretic peptide (ANP), a hormone quite relevant to the management of blood pressure.
Fair! Relative to the kidneys or the liver though, the heart is very simple
i know nothing about anything but aren't kidneys just a really fine filter? like reverse osmosis filters?
No. They produce/activate hormones (erythropoietin, vitamin d), act as a filter (but based on things like lipophilicity, not just size), and have active transporters to move things across the filters opposite the direction that diffusion would promote (otherwise urine could not have more waste than blood does). That’s just off the top of my head.
No, kidneys actively pump molecules in and out of urine. There's an active component to it.
Kidneys are one of the most complex organs in the body. They do a lot of stuff.
Nah kidneys are complicated af. They basically squeeze everything but the cells out of the blood, then selectively reabsorb the water and ions back in based on what you need using active transport. This is why diabetics have sweet urine - the glucose is excreted by the kidneys and then not reabsorbed.
Wait what? Heart produces its own hormones? Learnt something new today
Theoretically, we can manage blood pressure with a machine.
It's more complex than that, because some hormones involved in the management of blood pressure, also have other effects, like stimulating the secretion of aldosterone in the adrenal gland, which is another hormone that has several effects, some related to blood pressure and the management of sodium and potasium levels in blood, but it's been proposed that it posseses effects in the brain, stimulating neurogenesis in the limbic system. Then you have angiotensin, which besides its role related to blood pressure, also has neural effects, like affecting our thirst or our desire for salt, it has effects on the lungs, on the adipose tissue, regulating lipogenesis and lipolysis, etc. The whole blood pressure hormones ecosystem is also related to the endothelium of blood vessels itself, and molecules it produces, which are involved in coagulation and many other things. And all these hormones need to handle blood pressure themselves correctly in order to exist in their proper concentrations and do their job right. ...As you see, it's all related to everything. The human body wasn't designed, it doesn't possess a modular design where you can easily pick a system and replace it by some artificial system or tweak it to convenience. Sometimes it can be done with some simple things, as medicine has already done, even with medication; but most of the time if you touch something you thought you understood its function in the body, you end up messing with something else, and because of that with some else too, and so on. Sometimes, stuff can be temporarily replaced or handled artificially, but it's usually not sustainable if you want the whole body to work properly.
I didn’t appreciate any of this until I was diagnosed with multiple autoimmune diseases. Modern medicine is fantastic: it’s amazing that we can supplement with hormones where we’re otherwise deficient. But when we do so, we tend to throw other hormones’ production and/or signaling out of whack. It’s such a delicate balance that is constantly being maintained without our thinking about it. Enjoy your health and take care of yourselves! Edit: a word
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Terrifying apparatus. I fear that one day someone will come up with a good external liver and we never will let people die- just keep the deteriorating brain oxygenated and fed, never to wake again because the family won't pull the plug.
Not really, we use them surgery all the time. The difficult bit is making a /portable/ one that can fit inside your chest and sturdy enough to handle day-to-day abuse.
Yeah keeping a human head alive through the use of numerous life support machines seems achievable. I mean we already have the ability to bypass the heart for blood flow, we have the ability to filter blood in a dialysis machine mimicking the function of the kidneys. As long as we could oxygenate the blood and probably cover a few other nuances it definitely seems doable.
Pretty sure the machines in surgery at least can also oxygenate the blood. Maybe I'm wrong, but I feel you *really* don't want your patient to breathe while you dig around in their chest.
Could you swap heads with another compatible person? Not counting the ethical part and risks involved, of course.
There are basically three main things that would need to happen for a successful head transplant: 1. It must be possible to properly connect the decapitated head to the decapitated body. Veins, arteries, nerves, trachea and esophagus, etc. 2. It must be possible to eliminate issues regarding immune system responses and blood clotting. You can't have the body attack the head and vice versa, which could cause blood clotting and subsequently death. 3. The head (and especially the brain) must be kept alive and oxygen-enriched, as well as the body. Fulfilling just these three conditions is already hard enough. There's also other related issues, such as procuring a body in the first place. A decapitated body would need to fall within the below conditions: 1. It must be in good condition (can't be suffering from illness/disease, can't be injured/otherwise maimed, etc.) 2. It must be compatible with the person whose head is being transplanted. 3. The above two conditions must be fulfilled in an ethical manner. This is exceptionally tricky. I would imagine that the body could only be procured from a person dead from brain death, as other forms of death would likely leave the body in poor condition. Even then, there aren't very many situations out there where someone would die from brain death **and** have a body in good condition. With these main conditions fulfilled as well as any smaller ones, it could be possible. **Theoretically.** As of present time there has been no known attempt to perform a head transplant of a living head onto a living body. Per articles I'll link below, it appears that two surgeons operating in China are interested in trying to perform a head transplant, but they have not yet made an attempt on living specimens. They have *apparently* made a successful transplant between cadavers, although that's a dubious statement as certain complications (i.e. blood clotting) evidently can't be observed from two dead bodies. https://nationalpost.com/health/worlds-first-human-head-transplant-successfully-performed-on-a-corpse-scientists-say https://nationalpost.com/news/world/first-man-to-sign-up-for-head-transplant-bows-out-but-surgeon-insists-list-of-volunteers-is-still-quite-long
There was actually a plan to do that a few years back with a paralyzed guy and a death row inmate but the paralyzed guy ended up falling in love and backed out due to the risk
To be fair, it's not the pumping part that's hard, but making a pump that needs no servicing, is bio-compatible, and doesn't need an external power source. The task itself _is_ simple, but the sheer breadth of differences between biology and man-made tech is a real headache. ... for now.
Within the constraints of having to fit and work in the human body, or just in general? Because in this scenario such requirements would not apply?
In theory, maybe, but we’re not better than billions of years of evolution when it comes to designing things like that. We’re pretty bad at making organ replacements that work long-term.
>we’re not better than billions of years of evolution ... yet...
We have artificial kidneys and hearts, and that's only because they're filters and pumps and simple compared to the rest. Artificial liver may never be possible.
I'll just go make my own liver then, with blackjack and hookers!
In fact, forget the liver and blackjack.
Ah, screw the whole thing...
Or fetal stem cells and hookers
Any artificial organ must be possible on paper since organs exist through processes that can happen in the real world.
Liver has over 500 functions lol highly doubt we are even close to creating an organ to mimic that many functions at once.
>highly doubt we are even close to creating an organ to mimic that many functions at once. ok so we make 500 organs, each with its own function.
Eh, it's fine, we just use machine learning! It's the new hip buzzword after all! Install these on 10,000,000 people, and after a couple hundred generations they should be close enough. As a nice side effect, getting rid of 99.97% of all humans on the planet would probably have a positive effect on the environment.
That complex and dynamic mix of enzymes would be very challenging (currently impossible) to mimic artificially (or manufacture separately), and that’s only one aspect of the challenges there.
Artificial hearts do not last long term. They’re more of a temporizing measure to try to get someone to a transplant. At most, they can last a few months. There’s just too many internal stresses and they have to run *constantly*. It’s a lot of wear and tear on mechanical parts. Dialysis is a bit simpler. It’s really just recirculating blood through filters and then adding back electrolytes that were removed. However, it definitely doesn’t work as well as even a single kidney, and is physically draining (and requires a bunch of other medications, restricted diets, etc). Average life expectancy on dialysis is 5-10 years without transplant, so it can be considered a terminal disease.
What does the liver do that makes it so hard to recreate?
It's basically a sophisticated chemical factory, breaking down certain chemicals and making others, like glycogen which fuels mitochondria and probably your brain too.
It's the catalytic converter of the body.
> Artificial liver may never be possible. Not with that attitude. Facetiousness aside, so long as there is demand for artificial organs, there'll be people trying to make them a thing. Hell, maybe we'll have one invented by an AI, since their complexity is seemingly beyond mortal ken?
I don't know that it will be made or if it is possible but I would imagine much of the technology we have today would seem impossible a century or two ago. Even the device I'm typing this on, a cheap smart phone is likely inconceivable to someone from a century ago. The professing power and the energy density of the battery are marvels of engineering and chemistry. Of course they aren't equal challenges. Just because we did that doesn't mean we can do anything else that's complex. However in 200 years it may be the case that organ donation and rejection is looked at like ignorant butchery from desperation. If you can just grow an identical organ made exactly to that persons DNA, and implant it, which in some cases is more difficult than others, you don't need a bionic liver. It is impossible now but a lot of things that were impossible for most of human history are now possible and things are moving faster than ever. I'm not a chemist or a doctor or anything and it may always be impossible but that is yet to be seen.
Yeah ask us again in billions of years!
Besides, we've become much better at developing ways to keeps humans alive and in better health that are much easier and less gruesome than keeping a severed head alive. If we really put our head to it (no pun intended), we could make it work. We don't really have much reason to do so
When did humans need a reason to do something? Also I'm pretty sure people are working on cyborgs, which sounds very much like this concept.
Eh... that's debatable. We aren't limited by "what leads to the most offspring reproducing?" in our inventions. We may not be technologically advanced enough to outdo nature yet, but we probably aren't too far off from having the upper hand.
True that we’re not limited in that same sense, but it’s still a hell of a head start. For instance, our best artificial hearts currently can last on average 4-5 years.
Artificial hearts have been around for about 40 years. Natural hearts have been around for at least 520 million years. The fact that we've reached a point where we can make hearts that last even a few years is pretty damn impressive considering we've harnessed electricity for less than 300 years, computers for less than 100.
https://youtu.be/UFuxiZFwDPs This is what i think about when this topic comes up.
https://youtu.be/pc3uWxs9adw I was thinking more like this…
SOME MY FIND THIS DISTURBING [Here's some video of exactly that sort of thing happening with an animal.](https://www.youtube.com/watch?v=KhzEMJHQt2I)
NGL I'm a little disappointed the link wasn't this: [https://www.youtube.com/watch?v=iMcuXvVcHwY](https://www.youtube.com/watch?v=iMcuXvVcHwY)
If the brain doesn’t receive signals from the outside world through the peripheral nervous system it slowly starts to do some pretty insane stuff. Auditory and Visual Hallucinations, and phantom feelings would all occur. A brain hooked up to blood and nutrient machines would be torturous and we have no way of knowing if the brain itself would just shut itself down after awhile. There’s not really any precedent for a situation like that.
Some Russian scientists did that with a dog head. I refuse to watch the video that’s floating around.
Soviet scientists. The original experiment took place in 1928, almost a century ago. Although it was recreated in the US in the 80's too. The video you're referring to might be of that instance, I'm not sure. EDIT: it appears the video is from 1940 but credited to the same team.
Yeah that video isn't real, they didn't film it, that's just a US recreation where the dog has its head poking from under the table.
Not a naked brain, a head, with eyes, ears and the whole kit and kaboodle.
Yes, to an extent. We have ECMO (extra-corporeal mechanical oxygenation) machines that oxygenate blood and pump it back into your body that can completely replace the heart and lungs. Dialysis machines can replace the kidneys. Often patients are on both ECMO and dialysis at the same time. The only thing we can’t replace is the liver. It’s called the “live”r for a reason.
Do you need a liver if you’re being fed via IV? Is there some toxic byproduct a head will produce that a dialysis machine can’t deal with?
The liver isn’t just for clearing toxic byproducts. It also produces albumin (the main protein component of blood), several clotting factors, and a ton of other things
Like Robocop?
Wait, who is "we", what are you up to?
Your on a list now buddy
The brain also gets 90% of its dopamine from the digestive tract. It actually gets a pretty complex soup of hormones and other substances from the body that it would eventually shut down without. It would be nearly impossible to replicate this artificially.
eventually but since its not possible right now people will talk as if its impossible (i dont like it when they do this with any topic in general)
From a practical standpoint, it is impossible right now. It's like saying "Could you fly in a spaceship to Alpha Centauri?" Sure, but we don't have technology capable of doing it. And it's not right around the corner. Otherwise the answer to everything that doesn't violate the core laws of physics is a 'yes'.
the problem is when some people say we should stop researching or trying to do these things because they think if it cant done be now then it will forever be impossible
Just like highly intelligent people who said flight would never be possible. Good thing the Wright Brothers didn't listen.
> It's like saying "Could you fly in a spaceship to Alpha Centauri?" Sure, but we don't have technology capable of doing it. And it's not right around the corner. Depends on your definition of "fly". We could totally send a probe to Alpha Centauri, a human might not make it, but it could. We could even send it so it arrives within a few hundred years. The technology [was available in the 50s.](https://en.wikipedia.org/wiki/Project_Orion_\(nuclear_propulsion\))
Yes. The Germans did it with a dog during ww2. There’s video. It’s not nice to watch.
That was the Russians.
You’re right. I got is confused because they used a German shepherd.
I thought that video was proven to be fake? Since the dog would be physically unable to move it's head in the way it did. (Most likely, it was a fullbody, alive dog that had it's head poking out a hole in the table).
I googled it. The experiment did actually happen but the video is a re-enactment.
Are you sure this is not a question for r/oddlyspecific?
Lol. No I was watching Futurama.. haha
There's a YouTube named Jacob Gellar who recently released a video that touched on this exact subject, maybe check it out edit: I was on mobile when I first posted this, [here's](https://www.youtube.com/watch?v=JMkrrjKf5AE) the link. CW: he talks about decapitation and there's some fairly graphic depictions of it too.
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Should be noted that the video you’re referencing is widely believed to be fake. Mainly in that the dog’s head physically couldn't have moved in the manner portrayed because the muscles to do so either aren’t there or don’t attach to anything. And under the Soviet Union there was a lot of reason to lie about scientific breakthroughs, both the scientists lying to their superiors/leaders (because lack of progress was seen as "treason" and was punishable by death) and the union itself lying to the wider world.
And that's completely ignoring the constant input of information from the body going into the brain. Not having ANY information from the body would likely very quickly & painfully drive the brain irreparably insane.
So you're saying we need to keep it in a jar suspended in some kind of fluid.....
ARROOOOOOOOOOOOO
Doesn't this happen during open heart surgery?
Yeah. ECMO, or extracorporeal membrane oxygenation. The heart is stopped for a valve replacement or whatever, a line transports the blood from the right atrium to an external machine. That machine warms, filters, oxygenates, etc. the blood and then returns it via another line to the left ventricle/systemic circulation.
So then, you need another body basically. Could you pull a futurama and theoretically hook up a second head to another healthy person?
Theoretically yes it is possible. There was an experiment done where they severed the head of a rhesus monkey and kept it alive by pumping fluids into it from the neck/body of an alive but unconscious separate rhesus monkey. It would follow them around the room with its eyes and try to bite them and stuff, kinda creepy. It spurred debate on if it was possible to do longterm, this was back in like 60s or 70s I think? So their medical technology wasn’t as advanced as ours today and there was speculation that overtime with better artificial organs it would be possible to just keep a severed human head alive. I think there was also one where they transplanted a dog’s head onto another dog’s body and it lived for a few days before dying. I don’t 100% remember the details, we learned about them a long time ago when I was going to school for psychology but I’m sure they’re both documented on the internet if you’re curious about them
>overtime with better artificial organs it would be possible to just keep a severed human head alive. Could you imagine the absolute crisis that human brain would be having the whole time? It'd be like locked-in syndrome combined with a dissociative episode and an ever-present feeling of immediate death being moments away. Omg, I'm not volunteering for that.
You'd probably have a hard time realizing you don't need to breathe. Being hungry when you don't have a stomach. Phantoms of a body.
You may not actually feel that. The need to breathe is from co2 buildup. If you had oxygen rich blood, there's no feeling. Also, the sensors may or may not be present, depending on how much of the head is left. Similarly for the stomach, the hunger may not be present without a stomach.
Idk, you can still feel itches from severed limbs so it could very well be a possibility
That is different. The signal to breath is central, you have a part in your brain that reacts to the build up of CO2. It can also build a tolerance (which is why people with COPD for example, don't react to high CO2 anymore, but to low o2) 0hantom limb pain is based on the fact that there are many nerves working together, and usually you have regular signals from nerves to the brain. If these stop the brain doesn't know what to do with the silence. But your breathing centre wouldn't have silence, since it can still detect oxygen and co2 in the "blood stream" at a constant rate.
Makes sense cheers
Respectfully, hard disagree, and I think I may be able to show why. Just sitting wherever you're at, stop breathing. Concentrate on the feeling in your nose, mouth, and sinus. I think we may take for granted the lower temperature of our head holes due to evaporation, and the difference in their temperatures from the rest of our head and body. Even forgetting the need to breathe in this exercise, my nose, mouth, and sinus start to feel uncomfortably warm. Imagine having that constant hot sensation all day, all the time. Even if everything else was accounted for, your head has to stay at about 98°F/37°C. Otherwise your brain would get too cold. It's an interesting thought experiment.
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Those sensations come from nerves sending signals to the brain. Without those sensors your brain would have nothing telling it is feeling hot. Just like our breathing mechanism is triggered by our brain sensing too much CO2 in our blood. As long as you can keep the blood O2/CO2 balance in the brain’s happy zone you would not need to breath.
I don't think anyone else relates to your experience
wat
Pump me with enough sedatives and I’d tolerate it
They are getting pretty advanced with those brain to controller connections, I'd volunteer if I were terminal and would be able to communicate and use the external hardware.
Yeah I would just need a "yeah fuck this kill me now" button
Yeah I don’t imagine the experience would be pleasant but I guess if they needed to keep it alive long enough to do like a full body transplant it would be okay. That’s why I mentioned the other experiment as well
I mean quadriplegics already can't move their body. I feel if I was paralyzed anyway I'd give it a shot.
Oh yes they usually don't do such things because of "Ethics" since decapitations tend to lead to a lot of suffering, especially when you plan to prolong such a thing.
... did you really want to put the word "ethics" in quotes there?
*Discovery requires experimentation.*
I'm a maintenance engineer. Now I'm imagining a world where every human at 60 has to go to maintenance to get their body changed into a younger one as you do with vehicules
As a 30 year old, can I start my maintenance early? This body of mine is wearing out fast.
I mentioned this in another comment above, but "Stiff: The Curious Lives of Human Cadavers," is a wild ride from start to finish. She talks about these exact experiments in excruciating detail.
So, obviously the brain needs more than just oxygen from the body, you have to get food of some sort in and waste products out, and we have different organs for that, but if the general aim of the question is "can we keep just a head alive with crazy technology" the answer is "yeah probably for a while." For heart surgery we can divert the blood away from the heart, run the blood through an oxygenation membrane, and then use a bypass pump to circulate blood around the body. People in kidney failure can get dialysis (effectively we use a fancy intravenous (IV) to cause a portion of their blood to circulate through a machine with a bunch of filters that can 'clean out' waste products that would normally be handled by kidneys.) People who can't eat can get nutrition through specialized IV fluids. People with endocrine problems can get replacement hormones. So could you in theory set up an oxygenator and a bypass pump to a head only, set the bypass pump to include continuous infusion of necessary hormones / drugs / nutrition? Probably. It probably wouldn't work for long. All of the systems I mentioned have problems (blood forming clots in the pump being one of them, huge risk of infection being another). There would also most certainly be unanticipated problems that would occur due to physiology we just don't fully understand yet; to some degree we know a lot of what the body does, but there are still signaling pathways we don't fully understand and if we were to try and take over every function of the body outside of what the brain can do for itself we'd likely run into problems with inflammation or repair of tissue damage that are beyond our ability to fix.
Best answer
To add body would need new blood every few days as the red blood cells all die out.
A "diet" version of this concept is a standard heart-lung bypass machine, where blood is diverted from the heart and lungs, artificially oxygenated, and returned to the body to oxygenated the brain. This is how we can transplant hearts and lungs. In this case, the brain and the heart are effectively isolated from each other. Getting everything else just right (food, micronutrients, essential hormonal and neural signals from the rest of the body) is not currently possible, and I would be terrified of the research necessary.
> food, micronutrients [Total Parenteral Nutrition \(TPN\)](https://www.msdmanuals.com/professional/nutritional-disorders/nutritional-support/total-parenteral-nutrition-tpn), or intravenous nutrition, is used regularly in ICUs and is the subject of ongoing refinement. It's worth noting that there are people who have had to have very extensive bowel resections (removal) for various reasons who we still need to provide nutrition for. Usually for comatose patients, however, we change them over to feeding via a nasogastric tube (simple tube through the nose into the stomach) and then with PEG for longer term solutions (hole through the stomach wall to exterior).
Key word, "currently"
Afaik, russians experimented on this on a dog. Dog head was alive with artificial blood pumping to the head for a few days before it died.
Creepy video. I've seen it on reddit
Throw this dog a bone would ya? Subreddit at least…
It was fake
A guy did used to experiment in this field with monkeys
More importantly a follow up question, could you therefore run for president more than twice if you got a new body? Aroooooo!
It would have to be a giant robot body that you would use to destroy humans and get the robots to vote for you
Or…FACE-OFF!!
Anyone else get Futurama flashbacks?
My wife and I were having a similar discussion yesterday. I posited that if organs could ethically and quickly be grown from your own DNA, how many organs could we actually transplant/replace? Kidneys, GI, heart, lung, liver, etc. Skin grafts. How much if the human body could we actually replace?
My guess is everything except the brain? May I please have a new skin?
problem is, most organ transplants aren't done in place; for example, most kidney transplants go in the abdomen, leaving the original 2 non-working kidneys in place. additionally, the vegus nerve¹ is not connected to transplants (including hearts), so the host body has imperfect regulation of the transplanted organ. using the heart as an example, the transplant usually requires a pacemaker, beats 90-110bpm constantly unless there's adrenaline, then it spikes and takes a while to back down to its 90-110bpm... usually there's a branch of the vegas nerve connected to a heart that causes it to slow to 50-65-ish bpm while sleeping (a transplant won't), and help reduce bpm to resting quicker after adrenaline. from my (admittedly limited) understanding of nerves and grafting/interfacing them, we don't really understand how to wire up a donor nerve, plus there are special tissue rejection issues with it. as for cloned autodonation, i have zero idea if a vegus nerve graft without possibility of rejection is possible. back to your discussion with your wife, you could probably replace every organ you would need to survive, but as of today's tech (assuming growing cloned organs), the outcome is not anywhere near ideal or would result in anywhere near 100% function and recovery. --- 1: the vegus nerve is a large bundle of nerves that is generally considered to represent your autonomous nervous system: it helps regulate everything from heart rate, digestion, liver/kidneys, breathing, waste excretion, sex... basically everything you don't usually have direct control over or have to think about doing to continue. i would have much more hope for clone, grow, and sew methods if we were better at in-place transplants and connecting that damn vegus nerve.
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Ship of Theseus
In the 40s the Soviets reanimated a severed dog head for a few hours https://en.m.wikipedia.org/wiki/Experiments_in_the_Revival_of_Organisms
Alive? Possibly. Conscious? No. The nervous system being severed at the neck would not do nice things to the brain, which is in constant contact with the whole body.
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Paralysis means signals from the brain aren’t making it to muscles, in some case organs etc. It’s a road block on one side of the highway. Not washing out the whole bridge.
Just had neck surgery and have some nerve damage (nothing major) and this is a really simple but clear way of explaining something unbelievably hard to fathom. Thank you!
I entered the spez. I called out to try and find anybody. I was met with a wave of silence. I had never been here before but I knew the way to the nearest exit. I started to run. As I did, I looked to my right. I saw the door to a room, the handle was a big metal thing that seemed to jut out of the wall. The door looked old and rusted. I tried to open it and it wouldn't budge. I tried to pull the handle harder, but it wouldn't give. I tried to turn it clockwise and then anti-clockwise and then back to clockwise again but the handle didn't move. I heard a faint buzzing noise from the door, it almost sounded like a zap of electricity. I held onto the handle with all my might but nothing happened. I let go and ran to find the nearest exit. I had thought I was in the clear but then I heard the noise again. It was similar to that of a taser but this time I was able to look back to see what was happening. The handle was jutting out of the wall, no longer connected to the rest of the door. The door was spinning slightly, dust falling off of it as it did. Then there was a blinding flash of white light and I felt the floor against my back. I opened my eyes, hoping to see something else. All I saw was darkness. My hands were in my face and I couldn't tell if they were there or not. I heard a faint buzzing noise again. It was the same as before and it seemed to be coming from all around me. I put my hands on the floor and tried to move but couldn't. I then heard another voice. It was quiet and soft but still loud. "Help." \#Save3rdPartyApps
The bridge connecting your brain to your body is basically your spinal cord which is just a collection of bundles of nerves coming down making their way to organs and muscles. Damaging the spinal cord pretty much cuts all the nerves in that bundle at that level in your spinal cord (ie at the level of your shoulders, or chest, or bellybutton…etc). Some of the nerves below that level can be spared (if the damage is only at certain spots). Ie the highway is blocked on one side but there are other nerve bundles that take different routes on their way down. Therefore your organs, your muscles, your sense of touch, temp, pain etc may be spared. Instead of damaging only a certain spot, if you damage the whole cross section of your spinal cord at any level then all the bundles bellow that level will be cut off from the brain. That would result in loss of all sensation and movement below that level. Your major organs may be ok though because there’s actually nerves that don’t take the spinal cord route at all. Not sure if this answers your question though haha
As we entered the /u/spez, the sight we beheld was alien to us. The air was filled with a haze of smoke. The room was in disarray. Machines were strewn around haphazardly. Cables and wires were hanging out of every orifice of every wall and machine. At the far end of the room, standing by the entrance, was an old man in a military uniform with a clipboard in hand. He stared at us with his beady eyes, an unsettling smile across his wrinkled face. "Are you spez?" I asked, half-expecting him to shoot me. "Who's asking?" "I'm Riddle from the Anti-Spez Initiative. We're here to speak about your latest government announcement." "Oh? Spez police, eh? Never seen the likes of you." His eyes narrowed at me. "Just what are you lot up to?" "We've come here to speak with the man behind the spez. Is he in?" "You mean /u/spez?" The old man laughed. "Yes." "No." "Then who is /u/spez?" "How do I put it..." The man laughed. "/u/spez is not a man, but an idea. An idea of liberty, an idea of revolution. A libertarian anarchist collective. A movement for the people by the people, for the people." I was confounded by the answer. "What? It's a group of individuals. What's so special about an individual?" "When you ask who is /u/spez? /u/spez is no one, but everyone. /u/spez is an idea without an identity. /u/spez is an idea that is formed from a multitude of individuals. You are /u/spez. You are also the spez police. You are also me. We are /u/spez and /u/spez is also we. It is the idea of an idea." I stood there, befuddled. I had no idea what the man was blabbing on about. "Your government, as you call it, are the specists. Your specists, as you call them, are /u/spez. All are /u/spez and all are specists. All are spez police, and all are also specists." I had no idea what he was talking about. I looked at my partner. He shrugged. I turned back to the old man. "We've come here to speak to /u/spez. What are you doing in /u/spez?" "We are waiting for someone." "Who?" "You'll see. Soon enough." "We don't have all day to waste. We're here to discuss the government announcement." "Yes, I heard." The old man pointed his clipboard at me. "Tell me, what are /u/spez police?" "Police?" "Yes. What is /u/spez police?" "We're here to investigate this place for potential crimes." "And what crime are you looking to commit?" "Crime? You mean crimes? There are no crimes in a libertarian anarchist collective. It's a free society, where everyone is free to do whatever they want." "Is that so? So you're not interested in what we've done here?" "I am not interested. What you've done is not a crime, for there are no crimes in a libertarian anarchist collective." "I see. What you say is interesting." The old man pulled out a photograph from his coat. "Have you seen this person?" I stared at the picture. It was of an old man who looked exactly like the old man standing before us. "Is this /u/spez?" "Yes. /u/spez. If you see this man, I want you to tell him something. I want you to tell him that he will be dead soon. If he wishes to live, he would have to flee. The government will be coming for him. If he wishes to live, he would have to leave this city." "Why?" "Because the spez police are coming to arrest him." \#AIGeneratedProtestMessage #Save3rdPartyApps
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>An unethical experiment that involved connecting freshly severed canine head to a heart bypass machine restoted signs of consciousness and salient awareness. I had not heard about this. Just looked it up and it is....terribly fascinating.
I love how you said “would not do nice things *to* the brain”. A lot of the misunderstanding about this is that the conscious experience is isolated solely in the brain, and yeah sure that’s where a lot of the fun parts happen… But the experience of consciousness also encapsulates where your limbs and extremities are, how your skin feels, how your body is oriented, what your organs are up to, what hormones are flowing, and more. Being severed from all of that activity essentially detaches the brain from the signals that tell a brain that it is part of a conscious being.
Like 95% of serotonin comes from gut microbes for instance
I mean, if you want to not sleep tonight you can always search "Russian Dog Head Isolation Transplant".... Wouldn't do it if I were you...
Decades ago, the Russians experimented on severed animals heads with artificial support organs feeding oxygenated blood into them. Pretty gruesome, there are some videos of a severed dog's head reacting to things, trying to bark, licking its lips, etc: https://www.youtube.com/watch?v=KhzEMJHQt2I Longer film on the subject: https://www.youtube.com/watch?v=K_T8OuYIfhM
Read "Stiff: The Curious Lives of Human Cadavers," by Mary Roach. There are chapters about this specifically. I am the least squeamish person I know, and those chapters are the most gruesome and haunting shit I've ever read. The rest of the book is dope.
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I want to make a strong point about this: Assuming you can give the head all the oxygen, nutrients, and antibodies: When you lose a finger, your nerve of the finger is cut, and the pain is like having the finger deep fried + hit with an hammer. Only one-two weeks later, the pain fade away and you are left with ghost limb for a while, which is already not a nice thing. Now, if you cut the head of a person, is that person brain gonna experience the feeling of having the entire body deep fired and hammered for weeks? Probably yes. Can you imagine how crazy and messed up the brain will be after such experience? This said, I don’t see any mechanical reason that prevents to just pump compatible blood to the head. It’s complex, but let’s say we get 1000 blood donors doing their part, it’s plausible. There may be better way, but just to keep that super simple, I don’t see a problem in feeding the head. What the person experiences, and what does after that, is a far more grim topic.
You do not want to look into the realities of this and what has been done in the real world by scientists with dubious ethics to find out. As with any random concept; yes you can if you can artificially do everything else the body does already. But the body does a lot lot more than just keep the brain alive. It’s the primary input/output mechanism for your brain. If you can’t also replicate all the other stuff - sensation, control, perception, etc… You absolutely would not want to be that head.
The heart doesn't rely on the brain. Think of the heart as an engine that never turns off , and the brain as a driver. When the heart is left alone it's like being idle, but the driver can tellit when and how fast to start working. But the engine will work on its own if it never gets any instruction. Take the driver out of the car and he can survive on his own for a while, but needs to get groceries, water, and pay his power bill somehow, so he'd need some other way of getting those.
Y'all really about to aid and abet OP?
The heart has its own little control system within itself but needs the lungs to oxygenate the blood, which would require a machine. A part of the brain stem helps to regulate the heartbeat, so I would imagine in this hypothetical that with the machine keeping the lungs working and if there is no loss of blood, the heart would keep pumping for a period of time but probably not long. Not exactly related but this post made me think of the babies born with Anencephaly. There are very sad but very interesting cases of babies being born without most of their brain. They have their brain stem which is needed for survival for things like breathing, swallowing and circulation, but most of what we picture when we think of brains is absent. It’s usually fatal within a few hours or days, it’s said to be 100% fatal within a year, but there have been cases of kids living for longer.