Yale scientists restore cellular function in 32 dead pig brains
Researchers hope the technology will further our understanding of the brain, but lawmakers may not be ready for the ethical challenges.
- Researchers at the Yale School of Medicine successfully restored some functions to pig brains that had been dead for hours.
- They hope the technology will advance our understanding of the brain, potentially developing new treatments for debilitating diseases and disorders.
- The research raises many ethical questions and puts to the test our current understanding of death.
The image of an undead brain coming back to live again is the stuff of science fiction. Not just any science fiction, specifically B-grade sci fi. What instantly springs to mind is the black-and-white horrors of films like Fiend Without a Face. Bad acting. Plastic monstrosities. Visible strings. And a spinal cord that, for some reason, is also a tentacle?
But like any good science fiction, it's only a matter of time before some manner of it seeps into our reality. This week's Nature published the findings of researchers who managed to restore function to pigs' brains that were clinically dead. At least, what we once thought of as dead.
What's dead may never die, it seems
The researchers did not hail from House Greyjoy — "What is dead may never die" — but came largely from the Yale School of Medicine. They connected 32 pig brains to a system called BrainEx. BrainEx is an artificial perfusion system — that is, a system that takes over the functions normally regulated by the organ. The pigs had been killed four hours earlier at a U.S. Department of Agriculture slaughterhouse; their brains completely removed from the skulls.
BrainEx pumped an experiment solution into the brain that essentially mimic blood flow. It brought oxygen and nutrients to the tissues, giving brain cells the resources to begin many normal functions. The cells began consuming and metabolizing sugars. The brains' immune systems kicked in. Neuron samples could carry an electrical signal. Some brain cells even responded to drugs.
The researchers have managed to keep some brains alive for up to 36 hours, and currently do not know if BrainEx can have sustained the brains longer. "It is conceivable we are just preventing the inevitable, and the brain won't be able to recover," said Nenad Sestan, Yale neuroscientist and the lead researcher.
As a control, other brains received either a fake solution or no solution at all. None revived brain activity and deteriorated as normal.
The researchers hope the technology can enhance our ability to study the brain and its cellular functions. One of the main avenues of such studies would be brain disorders and diseases. This could point the way to developing new of treatments for the likes of brain injuries, Alzheimer's, Huntington's, and neurodegenerative conditions.
"This is an extraordinary and very promising breakthrough for neuroscience. It immediately offers a much better model for studying the human brain, which is extraordinarily important, given the vast amount of human suffering from diseases of the mind [and] brain," Nita Farahany, the bioethicists at the Duke University School of Law who wrote the study's commentary, told National Geographic.
An ethical gray matter
Before anyone gets an Island of Dr. Moreau vibe, it's worth noting that the brains did not approach neural activity anywhere near consciousness.
The BrainEx solution contained chemicals that prevented neurons from firing. To be extra cautious, the researchers also monitored the brains for any such activity and were prepared to administer an anesthetic should they have seen signs of consciousness.
Even so, the research signals a massive debate to come regarding medical ethics and our definition of death.
Most countries define death, clinically speaking, as the irreversible loss of brain or circulatory function. This definition was already at odds with some folk- and value-centric understandings, but where do we go if it becomes possible to reverse clinical death with artificial perfusion?
"This is wild," Jonathan Moreno, a bioethicist at the University of Pennsylvania, told the New York Times. "If ever there was an issue that merited big public deliberation on the ethics of science and medicine, this is one."
One possible consequence involves organ donations. Some European countries require emergency responders to use a process that preserves organs when they cannot resuscitate a person. They continue to pump blood throughout the body, but use a "thoracic aortic occlusion balloon" to prevent that blood from reaching the brain.
The system is already controversial because it raises concerns about what caused the patient's death. But what happens when brain death becomes readily reversible? Stuart Younger, a bioethicist at Case Western Reserve University, told Nature that if BrainEx were to become widely available, it could shrink the pool of eligible donors.
"There's a potential conflict here between the interests of potential donors — who might not even be donors — and people who are waiting for organs," he said.
It will be a while before such experiments go anywhere near human subjects. A more immediate ethical question relates to how such experiments harm animal subjects.
Ethical review boards evaluate research protocols and can reject any that causes undue pain, suffering, or distress. Since dead animals feel no pain, suffer no trauma, they are typically approved as subjects. But how do such boards make a judgement regarding the suffering of a "cellularly active" brain? The distress of a partially alive brain?
The dilemma is unprecedented.
Setting new boundaries
Another science fiction story that comes to mind when discussing this story is, of course, Frankenstein. As Farahany told National Geographic: "It is definitely has [sic] a good science-fiction element to it, and it is restoring cellular function where we previously thought impossible. But to have Frankenstein, you need some degree of consciousness, some 'there' there. [The researchers] did not recover any form of consciousness in this study, and it is still unclear if we ever could. But we are one step closer to that possibility."
She's right. The researchers undertook their research for the betterment of humanity, and we may one day reap some unimaginable medical benefits from it. The ethical questions, however, remain as unsettling as the stories they remind us of.
- Why Cryogenics Is Bogus - Big Think ›
- Factory farm death rate of pig sows increases sharply - Big Think ›
Dominique Crenn, the only female chef in America with three Michelin stars, joins Big Think Live this Thursday at 1pm ET.
Welcome to the world's newest motorsport: manned multicopter races that exceed speeds of 100 mph.
- Airspeeder is a company that aims to put on high-speed races featuring electric flying vehicles.
- The so-called Speeders are able to fly at speeds of up to 120 mph.
- The motorsport aims to help advance the electric vertical take-off and landing (eVTOL) sector, which could usher in the age of air taxis.
Credit: Airspeeder<p>To prevent crashes, Airspeeder is working with the companies Acronis and Teknov8 to develop "high-speed collision avoidance" systems for its Speeders.</p><p style="margin-left: 20px;">"As they compete, Speeders will utilise cutting-edge LiDAR and Machine Vision technology to ensure close but safe racing, with defined and digitally governed no-fly areas surrounding spectators and officials," Airspeeder wrote in a <a href="https://airspeeder.com/news/2020/9/7/airspeeder-worlds-first-flying-electric-car-racing-series-partners-with-cyber-protection-leader-acronis-34g4k" target="_blank">blog post</a>.</p>
Credit: Airspeeder<p>Beyond motorsports, Airspeeder hopes to help advance the electric vertical take-off and landing (eVTOL) sector. This sector is where companies like <a href="https://www.ainonline.com/aviation-news/business-aviation/2020-01-07/hyundai-and-uber-announce-evtol-air-taxi-partnership" target="_blank">Uber, Hyundai</a>, and Airbus are working to develop air taxis, which could someday take the ridesharing industry into the skies. By 2040, the autonomous urban aircraft industry could be worth $1.5 trillion, according to a <a href="https://www.morganstanley.com/ideas/autonomous-aircraft" target="_blank">2019 report</a> from Morgan Stanley.</p><p>Still, many technical and regulatory hurdles remain. Matt Pearson, Airspeeder's founder and CEO, thinks the futuristic motorsport will help to not only speed up that process, but also pave the way for self-driving cars.</p>
Astronomers spot an object heading into Earth orbit.
Minimoons<p>Scientists have confirmed just two prior minimoons. One was <a href="https://en.wikipedia.org/wiki/2006_RH120" target="_blank">2006 RH120</a>, which orbited us from September 2006 to June 2007. The other was <a href="https://en.wikipedia.org/wiki/2020_CD3" target="_blank">2020 CD3</a>, which got stuck in the 2015–2016 timeframe, and is believed to gotten away in May 2020.</p><p>2020 SO, the new kid on the block, is expected to arrive in October 2020 and pop out of orbit in May 2021.</p><div id="37962" class="rm-shortcode" data-rm-shortcode-id="f4c0fc8a2cba6536ea4cd960ebed3e6e"><blockquote class="twitter-tweet twitter-custom-tweet" data-twitter-tweet-id="1307729521869611008" data-partner="rebelmouse"><div style="margin:1em 0">Asteroid 2020 SO may get captured by Earth from Oct 2020 - May 2021. Current nominal trajectory shows shows capture… https://t.co/F5utxRvN6Z</div> — Tony Dunn (@Tony Dunn)<a href="https://twitter.com/tony873004/statuses/1307729521869611008">1600621989.0</a></blockquote></div>
Identifying 2020 SO<p>The first clue 2020 SO isn't your ordinary asteroid is its exceptionally low velocity. It's traveling much more slowly that a typical asteroid — their <a href="https://www.lpi.usra.edu/exploration/training/illustrations/craterMechanics/" target="_blank">average rate of travel</a> <a href="https://www.lpi.usra.edu/exploration/training/illustrations/craterMechanics/" target="_blank" rel="noopener noreferrer"></a>is 18 kilometers (58,000 feet) per second. Even <a href="https://en.wikipedia.org/wiki/Moon_rock" target="_blank">moon rocks</a> sent careening into Earth orbit by impacts on the lunar surface outpace pokey 2020 SO.</p><p>For another thing, 2020 SO has an orbital path very similar to Earth's, lasting about one Earth year. It's also just slightly less circular than our own orbit, from which it's barely tilted off-axis.</p><p>So, what is it? <a href="https://cneos.jpl.nasa.gov/ca/" target="_blank">NASA estimates</a> that the object has dimensions very reminiscent of a discarded Centaur rocket stage from the <a href="https://en.wikipedia.org/wiki/Surveyor_2" target="_blank" rel="noopener noreferrer">Surveyor 2 mission</a> that landed an unmanned craft on the moon. Back in the day, rocket stages were jettisoned as craft were aimed toward their desired position. This stuff, if released high enough, remains in space. It appears that this Centaur rocket, launched in September 1966, is now making its way back homeward, at least for a little bit.</p><p>When 2020 SO arrives at its closest point in December, the rocket is expected to be about 50,000 kilometers from Earth. Its next closest approach is much further: 220,000 kilometers, in February 2010.</p><img type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8yNDQzMDk3NC9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTYyODg1MTQ1MX0.HGknDwqp0GmeuczKY_AS7vrPG7KMFUc_XO95tNoI2xo/img.jpg?width=980" id="e5cda" class="rm-shortcode" data-rm-shortcode-id="85eb1f790d8c3ee5b261f7ba13eaa5e1" data-rm-shortcode-name="rebelmouse-image" alt="Centaur rocket stage" />
Centaur rocket stage
What we may be able to learn<p>Earthly space programs being as young as they are, scientists would love to know what's happened to our rocket during a half century in space.</p><p>While 2020 SO won't get close enough to drop into our atmosphere, its slow progress has scientists hopeful that they'll still get some kind of a decent look at it.</p><p>Spectroscopy may be able to reveal what the rocket's surface is like now — has any of its paint survived, for example? Of course, being out in space, it's likely to have been hit by lots of dust and micrometeorites, so the current state of its surfaces is also of interest. Experts are curious to know how reflective the rocket is at this point, valuable information that can help planners of future long-term missions anticipate how well a craft out in space for extended periods will remain able to reflect sunlight.</p>
From cryonics to time travel, here are some of the (highly speculative) methods that might someday be used to bring people back to life.
- Alexey Turchin and Maxim Chernyakov, researchers belonging to the transhumanism movement, wrote a paper outlining the main ways technology might someday make resurrection possible.
- The methods are highly speculative, ranging from cryonics to digital reconstruction of individual personalities.
- Surveys suggest most people would not choose to live forever if given the option.
Immortality and identity<p>The paper defines life as a "continued stream of subjective experiences" and death as the permanent end of that stream. Immortality, to them, is a "life stream without end," and resurrection is the "continuation of that same stream of experiences after an arbitrarily long gap."</p><p>Another key clarification is the identity problem: How would you know that a downloaded copy of yourself really was going to be <em>you? </em>Couldn't it just be a convincing yet incomplete and fundamentally distinct representation of your brain?</p><p>If you believe that your copy is not <em>you</em>, that implies you believe there's something more to your identity than the (currently) quantifiable information contained within your brain and body, according to the researchers. In other words, your "informational identity" does not constitute your true identity.</p><p>In this scenario, there must exist what the researchers call a "non-informational identity carrier" (NIIC). This could be something like a "soul." It could be "qualia," which are the unmeasurable "subjective experiences which could be unique to every person." Or maybe it doesn't exist at all.</p><p>It's no matter: The researchers say resurrection, in some form, should be possible in either scenario.</p><p style="margin-left: 20px;">"If no 'soul' exist[s], resurrection is possible via information preservation; if soul[s] exist, resurrection is possible via returning of the "soul" into the new body. But some forms of NIIC are also very fragile and mortal, like continuity," the researchers noted.</p><p style="margin-left: 20px;">"The problem of the nature of human identity could be solved by future superintelligent AI, but for now it cannot be definitively solved. This means that we should try to preserve as much identity as possible and not refuse any approaches to life extension and resurrection even if they contradict our intuitions about identity, as our notions of identity could change later."</p>
Potential resurrection methods<p>Turchin and Chernyakov outline seven broad categories of potential resurrection methods, ranked from the most plausible to most speculative.<br></p><p>The first category includes methods practiced while the person is alive, like cryonics, plastination, and preserving brain tissue through processes like chemical fixation. The researchers noted that there have been "suggestions that the claustrum, hypothalamus, or even a single neuron is the neural correlate of consciousness," so it may be possible to preserve just that part of a person, and later implant it into another organism.</p><p>Other methods get far stranger. For example, one method includes super-intelligent AI that uses a <a href="https://en.wikipedia.org/wiki/Dyson_sphere#:~:text=A%20Dyson%20sphere%20is%20a,percentage%20of%20its%20power%20output." target="_blank">Dyson sphere</a> to harness the power of the sun to "power enormous calculation engines" that would "reconstruct" people who collected a sufficient amount of data on their identities.</p>
Turchin<p style="margin-left: 20px;">"The main idea of a resurrection-simulation is that if one takes the DNA of a past person and subjects it to the same developmental condition, as well as correcting the development based on some known outcomes, it is possible to create a model of a past person which is very close to the original," the researchers wrote.</p><p style="margin-left: 20px;">"DNA samples of most people who lived in past 1 to 2 centuries could be extracted via global archeology. After the moment of death, the simulated person is moved into some form of the afterlife, perhaps similar to his religious expectations, where he meets his relatives."</p><p>Delving further into sci-fi territory, another resurrection method would use time-travel technology.</p><p style="margin-left: 20px;">"If there will at some point be technology that allows travel to the past, then our future descendants will be able to directly save people dying in the past by collecting their brains at the moment of death and replacing them with replicas," the paper states.</p><p>How? Sending tiny robots back in time.</p><p style="margin-left: 20px;">"A nanorobot could be sent several billion years before now, where it could secretly replicate and sow nanotech within all living being[s] without affecting the course of history. At the moment of death, such nanorobots could be activated to collect data about the brain and preserve it somewhere until its future resurrection; thus, there would be no need for forward time travel."</p>
Pixabay<p>The paper <a href="https://www.academia.edu/36998733/Classification_of_the_approaches_to_the_technological_resurrection" target="_blank">goes on to outline some more resurrection methods</a>, including ones that involve parallel worlds, aliens, and clones, along with a good, old-fashioned possibility: God exists and one day he resurrects us. </p><p>In short, it's all extremely speculative.</p><p>But the aim of the paper was to catalogue known potential ways humans might be able to cheat death. For Turchin, that's not some far-off project: In addition to studying global risks and transhumanism, the Russian researcher heads the <a href="http://immortality-roadmap.com/" target="_blank">Immortality Roadmap</a>, which, similar to the 2018 paper, outlines various ways in which we might someday achieve immortality.</p><p>Although it may take centuries before humans come close to "digital immortality," Turchin believes that life-extension technology could allow some modern people to survive long enough to see it happen. </p><p>Want a shot at being among them? Beyond the obvious, like staying healthy, the Immortality Roadmap suggests you start collecting extensive data on yourself: diaries, video recordings, DNA information, EEGs, complex creative objects — all of which could someday be used to digitally "reconstruct" your identity.</p>But odds are you're not interested. Although Turchin and other scientists are bent on finding ways to avoid death and extend life indefinitely, <a href="https://www.theguardian.com/uk/2011/may/16/dying-still-taboo-subject-poll" target="_blank" rel="noopener noreferrer">surveys</a> <a href="https://quillette.com/2018/03/02/would-you-opt-for-immortality/" target="_blank" rel="noopener noreferrer">repeatedly</a> <a href="https://www.cbsnews.com/news/60-minutesvanity-fair-poll-the-afterlife/" target="_blank" rel="noopener noreferrer">show</a> that most people would not opt to live forever if given the choice.