Few images are more uncanny than that of a brain without a body, fully sentient but afloat in sterile isolation. Such specters have spooked the speculatively-minded since the seventeenth century, when René Descartes declared, "I think, therefore I am."
Since August 29, 2019, the prospect of a bodiless but functional brain has begun to seem far less fantastical.
In Meditations on First Philosophy (1641), the French penseur spins a chilling thought experiment: he imagines "having no hands or eyes, or flesh, or blood or senses," but being tricked by a demon into believing he has all these things, and a world to go with them. A disembodied brain itself becomes a demon in the classic young-adult novel A Wrinkle in Time (1962), using mind control to subjugate a planet called Camazotz. In the sci-fi blockbuster The Matrix (1999), most of humanity endures something like Descartes' nightmare—kept in womblike pods by their computer overlords, who fill the captives' brains with a synthetized reality while tapping their metabolic energy as a power source.
Since August 29, 2019, however, the prospect of a bodiless but functional brain has begun to seem far less fantastical. On that date, researchers at the University of California, San Diego published a study in the journal Cell Stem Cell, reporting the detection of brainwaves in cerebral organoids—pea-size "mini-brains" grown in the lab. Such organoids had emitted random electrical impulses in the past, but not these complex, synchronized oscillations. "There are some of my colleagues who say, 'No, these things will never be conscious,'" lead researcher Alysson Muotri, a Brazilian-born biologist, told The New York Times. "Now I'm not so sure."
Alysson Muotri has no qualms about his creations attaining consciousness as a side effect of advancing medical breakthroughs.
(Credit: ZELMAN STUDIOS)
Muotri's findings—and his avowed ambition to push them further—brought new urgency to simmering concerns over the implications of brain organoid research. "The closer we come to his goal," said Christof Koch, chief scientist and president of the Allen Brain Institute in Seattle, "the more likely we will get a brain that is capable of sentience and feeling pain, agony, and distress." At the annual meeting of the Society for Neuroscience, researchers from the Green Neuroscience Laboratory in San Diego called for a partial moratorium, warning that the field was "perilously close to crossing this ethical Rubicon and may have already done so."
Yet experts are far from a consensus on whether brain organoids can become conscious, whether that development would necessarily be dreadful—or even how to tell if it has occurred.
So how worried do we need to be?
An organoid is a miniaturized, simplified version of an organ, cultured from various types of stem cells. Scientists first learned to make them in the 1980s, and have since turned out mini-hearts, lungs, kidneys, intestines, thyroids, and retinas, among other wonders. These creations can be used for everything from observation of basic biological processes to testing the effects of gene variants, pathogens, or medications. They enable researchers to run experiments that might be less accurate using animal models and unethical or impractical using actual humans. And because organoids are three-dimensional, they can yield insights into structural, developmental, and other matters that an ordinary cell culture could never provide.
In 2006, Japanese biologist Shinya Yamanaka developed a mix of proteins that turned skin cells into "pluripotent" stem cells, which could subsequently be transformed into neurons, muscle cells, or blood cells. (He later won a Nobel Prize for his efforts.) Developmental biologist Madeline Lancaster, then a post-doctoral student at the Institute of Molecular Biotechnology in Vienna, adapted that technique to grow the first brain organoids in 2013. Other researchers soon followed suit, cultivating specialized mini-brains to study disorders ranging from microcephaly to schizophrenia.
Muotri, now a youthful 45-year-old, was among the boldest of these pioneers. His team revealed the process by which Zika virus causes brain damage, and showed that sofosbuvir, a drug previously approved for hepatitis C, protected organoids from infection. He persuaded NASA to fly his organoids to the International Space Station, where they're being used to trace the impact of microgravity on neurodevelopment. He grew brain organoids using cells implanted with Neanderthal genes, and found that their wiring differed from organoids with modern DNA.
Like the latter experiment, Muotri's brainwave breakthrough emerged from a longtime obsession with neuroarchaeology. "I wanted to figure out how the human brain became unique," he told me in a phone interview. "Compared to other species, we are very social. So I looked for conditions where the social brain doesn't function well, and that led me to autism." He began investigating how gene variants associated with severe forms of the disorder affected neural networks in brain organoids.
Tinkering with chemical cocktails, Muotri and his colleagues were able to keep their organoids alive far longer than earlier versions, and to culture more diverse types of brain cells. One team member, Priscilla Negraes, devised a way to measure the mini-brains' electrical activity, by planting them in a tray lined with electrodes. By four months, the researchers found to their astonishment, normal organoids (but not those with an autism gene) emitted bursts of synchronized firing, separated by 20-second silences. At nine months, the organoids were producing up to 300,000 spikes per minute, across a range of frequencies.
He shared his vision for "brain farms," which would grow organoids en masse for drug development or tissue transplants.
When the team used an artificial intelligence system to compare these patterns with EEGs of gestating fetuses, the program found them to be nearly identical at each stage of development. As many scientists noted when the news broke, that didn't mean the organoids were conscious. (Their chaotic bursts bore little resemblance to the orderly rhythms of waking adult brains.) But to some observers, it suggested that they might be approaching the borderline.
Shortly after Muotri's team published their findings, I attended a conference at UCSD on the ethical questions they raised. The scientist, in jeans and a sky-blue shirt, spoke rhapsodically of brain organoids' potential to solve scientific mysteries and lead to new medical treatments. He showed video of a spider-like robot connected to an organoid through a computer interface. The machine responded to different brainwave patterns by walking or stopping—the first stage, Muotri hoped, in teaching organoids to communicate with the outside world. He described his plans to develop organoids with multiple brain regions, and to hook them up to retinal organoids so they could "see." He shared his vision for "brain farms," which would grow organoids en masse for drug development or tissue transplants.
Muotri holds a spider-like robot that can connect to an organoid through a computer interface.
(Credit: ROLAND LIZARONDO/KPBS)
Yet Muotri also stressed the current limitations of the technology. His organoids contain approximately 2 million neurons, compared to about 200 million in a rat's brain and 86 billion in an adult human's. They consist only of a cerebral cortex, and lack many of a real brain's cell types. Because researchers haven't yet found a way to give organoids blood vessels, moreover, nutrients can't penetrate their inner recesses—a severe constraint on their growth.
Another panelist strongly downplayed the imminence of any Rubicon. Patricia Churchland, an eminent philosopher of neuroscience, cited research suggesting that in mammals, networked connections between the cortex and the thalamus are a minimum requirement for consciousness. "It may be a blessing that you don't have the enabling conditions," she said, "because then you don't have the ethical issues."
Christof Koch, for his part, sounded much less apprehensive than the Times had made him seem. He noted that science lacks a definition of consciousness, beyond an organism's sense of its own existence—"the fact that it feels like something to be you or me." As to the competing notions of how the phenomenon arises, he explained, he prefers one known as Integrated Information Theory, developed by neuroscientist Giulio Tononi. IIT considers consciousness to be a quality intrinsic to systems that reach a certain level of complexity, integration, and causal power (the ability for present actions to determine future states). By that standard, Koch doubted that brain organoids had stepped over the threshold.
One way to tell, he said, might be to use the "zap and zip" test invented by Tononi and his colleague Marcello Massimini in the early 2000s to determine whether patients are conscious in the medical sense. This technique zaps the brain with a pulse of magnetic energy, using a coil held to the scalp. As loops of neural impulses cascade through the cerebral circuitry, an EEG records the firing patterns. In a waking brain, the feedback is highly complex—neither totally predictable nor totally random. In other states, such as sleep, coma, or anesthesia, the rhythms are simpler. Applying an algorithm commonly used for computer "zip" files, the researchers devised a scale that allowed them to correctly diagnose most patients who were minimally conscious or in a vegetative state.
If scientists could find a way to apply "zap and zip" to brain organoids, Koch ventured, it should be possible to rank their degree of awareness on a similar scale. And if it turned out that an organoid was conscious, he added, our ethical calculations should strive to minimize suffering, and avoid it where possible—just as we now do, or ought to, with animal subjects. (Muotri, I later learned, was already contemplating sensors that would signal when organoids were likely in distress.)
During the question-and-answer period, an audience member pressed Churchland about how her views might change if the "enabling conditions" for consciousness in brain organoids were to arise. "My feeling is, we'll answer that when we get there," she said. "That's an unsatisfying answer, but it's because I don't know. Maybe they're totally happy hanging out in a dish! Maybe that's the way to be."
Muotri himself admits to no qualms about his creations attaining consciousness, whether sooner or later. "I think we should try to replicate the model as close as possible to the human brain," he told me after the conference. "And if that involves having a human consciousness, we should go in that direction." Still, he said, if strong evidence of sentience does arise, "we should pause and discuss among ourselves what to do."
"The field is moving so rapidly, you blink your eyes and another advance has occurred."
Churchland figures it will be at least a decade before anyone reaches the crossroads. "That's partly because the thalamus has a very complex architecture," she said. It might be possible to mimic that architecture in the lab, she added, "but I tend to think it's not going to be a piece of cake."
If anything worries Churchland about brain organoids, in fact, it's that Muotri's visionary claims for their potential could set off a backlash among those who find them unacceptably spooky. "Alysson has done brilliant work, and he's wonderfully charismatic and charming," she said. "But then there's that guy back there who doesn't think it's exciting; he thinks you're the Devil incarnate. You're playing into the hands of people who are going to shut you down."
Koch, however, is more willing to indulge Muotri's dreams. "Ten years ago," he said, "nobody would have believed you can take a stem cell and get an entire retina out of it. It's absolutely frigging amazing. So who am I to say the same thing can't be true for the thalamus or the cortex? The field is moving so rapidly, you blink your eyes and another advance has occurred."
The point, he went on, is not to build a Cartesian thought experiment—or a Matrix-style dystopia—but to vanquish some of humankind's most terrifying foes. "You know, my dad passed away of Parkinson's. I had a twin daughter; she passed away of sudden death syndrome. One of my best friends killed herself; she was schizophrenic. We want to eliminate all these terrible things, and that requires experimentation. We just have to go into it with open eyes."
Jessica Ware is obsessed with bugs.
My guest today is a leading researcher on insects, the president of the Entomological Society of America and a curator at the American Museum of Natural History. Learn more about her here.
You may not think that insects and human health go hand-in-hand, but as Jessica makes clear, they’re closely related. A lot of people care about their health, and the health of other creatures on the planet, and the health of the planet itself, but researchers like Jessica are studying another thing we should be focusing on even more: how these seemingly separate areas are deeply entwined. (This is the theme of an upcoming event hosted by Leaps.org and the Aspen Institute.)
Listen to the Episode
Entomologist Jessica Ware
D. Finnin / AMNH
Maybe it feels like a core human instinct to demonize bugs as gross. We seem to try to eradicate them in every way possible, whether that’s with poison, or getting out our blood thirst by stomping them whenever they creep and crawl into sight.
But where did our fear of bugs really come from? Jessica makes a compelling case that a lot of it is cultural, rather than in-born, and we should be following the lead of other cultures that have learned to live with and appreciate bugs.
The truth is that a healthy planet depends on insects. You may feel stung by that news if you hate bugs. Reality bites.
Jessica and I talk about whether learning to live with insects should include eating them and gene editing them so they don’t transmit viruses. She also tells me about her important research into using genomic tools to track bugs in the wild to figure out why and how we’ve lost 50 percent of the insect population since 1970 according to some estimates – bad news because the ecosystems that make up the planet heavily depend on insects. Jessica is leading the way to better understand what’s causing these declines in order to start reversing these trends to save the insects and to save ourselves.
The first thing Jeroen Perk saw after he partially regained his sight nearly a decade ago was the outline of his guide dog Pedro.
“There was a white floor, and the dog was black,” recalls Perk, a 43-year-old investigator for the Dutch customs service. “I was crying. It was a very nice moment.”
Perk was diagnosed with retinitis pigmentosa as a child and had been blind since early adulthood. He has been able to use the implant placed into his retina in 2013 to help identify street crossings, and even ski and pursue archery. A video posted by the company that designed and manufactured the device indicates he’s a good shot.
Less black-and-white has been the journey Perk and others have been on after they were implanted with the Argus II, a second-generation device created by a Los Angeles-based company called Second Sight Medical Devices.
The Argus II uses the implant and a video camera embedded in a special pair of glasses to provide limited vision to those with retinitis pigmentosa, a genetic disease that causes cells in the retina to deteriorate. The camera feeds information to the implant, which sends electrical impulses into the retina to recapitulate what the camera sees. The impulses appear in the Argus II as a 60-pixel grid of blacks, grays and whites in the user’s eye that can render rough outlines of objects and their motion.
Smartphone and computer manufacturers typically stop issuing software upgrades to their devices after two or three years, eventually rendering them bricks. But is the smartphone approach acceptable for a device that helps restore the most crucial sense a human being possesses?
Ross Doerr, a retired disability rights attorney in Maine who received an Argus II in 2019, describes the field of vision as the equivalent of an index card held at arm’s length. Perk often brings objects close to his face to decipher them. Moreover, users must swivel their heads to take in visual data; moving their eyeballs does not work.
Despite its limitations, the Argus II beats the alternative. Perk no longer relies on his guide dog. Doerr was uplifted when he was able to see the outlines of Christmas trees at a holiday show.
“The fairy godmother department sort of reaches out and taps you on the shoulder once in a while,” Doerr says of his implant, which came about purely by chance. A surgeon treating his cataracts was partnered with the son of another surgeon who was implanting the devices, and he was referred.
Doerr had no reason to believe the shower of fairy dust wouldn’t continue. Second Sight held out promises that the Argus II recipients’ vision would gradually improve through upgrades to much higher pixel densities. The ability to recognize individual faces was even touted as a possibility. In the winter of 2020, Doerr was preparing to travel across the U.S. to Second Sight’s headquarters to receive an upgrade. But then COVID-19 descended, and the trip was canceled.
The pandemic also hit Second Sight’s bottom line. Doerr found out about its tribulations only from one of the company’s vision therapists, who told him the entire department was being laid off. Second Sight cut nearly 80% of its workforce in March 2020 and announced it would wind down operations.
Ross Doerr has mostly stopped using his Argus II, the result of combination of fear of losing its assistance from wear and tear and disdain for the company that brought it to market.
Second Sight’s implosion left some 350 Argus recipients in the metaphorical dark about what to do if their implants failed. Skeleton staff seem to have rarely responded to queries from their customers, at least based on the experiences of Perk and Doerr. And some recipients have unfortunately returned to the actual dark as well, as reports have surfaced of Argus II failures due to aging or worn-down parts.
Product support for complex products is remarkably uneven. Although the iconic Ford Mustang ceased production in the late 1960s, its parts market is so robust that it’s theoretically possible to assemble a new vehicle from recently crafted components. Conversely, smartphone and computer manufacturers typically stop issuing software upgrades to their devices after two or three years, eventually rendering them bricks. Consumers have accepted both extremes.
But is the smartphone approach acceptable for a device that helps restore the most crucial sense a human being possesses?
Margaret McLean, a senior fellow at the Markkula Center for Applied Ethics at Santa Clara University in California, notes companies like Second Sight have a greater obligation for product support than other consumer product ventures.
“In this particular case, you have a great deal of risk that is involved in using this device, the implant, and the after care of this device,” she says. “You cannot, like with your car, decide that ‘I don’t like my Mustang anymore,’ and go out and buy a Corvette.”
And, whether the Argus II implant works or not, its physical presence can impact critical medical decisions. Doerr’s doctor wanted him to undergo an MRI to assist in diagnosing attacks of vertigo. But the physician was concerned his implant might interfere. With the latest available manufacturer advisories on his implant nearly a decade old, the procedure was held up. Doerr spent months importuning Second Sight through phone calls, emails and Facebook postings to learn if his implant was contraindicated with MRIs, which he never received. Although the cause of his vertigo was found without an MRI, Doerr was hardly assured.
“Put that into context for a minute. I get into a serious car accident. I end up in the emergency room, and I have a tag saying I have an implanted medical device,” he says. “You can’t do an MRI until you get the proper information from the company. Who’s going to answer the phone?”
Second Sight’s management did answer the call to revamp its business. It netted nearly $78 million through a private stock placement and an initial public offering last year. At the end of 2021, Second Sight had nearly $70 million in cash on hand, according to a recent filing with the Securities and Exchange Commission.
And while the Argus II is still touted at length on Second Sight’s home page, it appears little of its corporate coffers are earmarked toward its support. These days, the company is focused on obtaining federal approvals for Orion, a new implant that would go directly into the recipient’s brain and could be used to remedy blindness from a variety of causes. It obtained a $6.4 million grant from the National Institutes of Health in May 2021 to help develop Orion.
Presented with a list of written questions by email, Second Sight’s spokesperson, Dave Gentry of the investor relations firm Red Chip Companies, copied a subordinate with an abrupt message to “please handle.” That was the only response from a company representative. A call to Second Sight acting chief executive officer Scott Dunbar went unreturned.
Whether or not the Orion succeeds remains to be seen. The company’s SEC filings suggest a viable and FDA-approved device is years away, and that operational losses are expected for the “foreseeable future.” Second Sight reported zero revenue in 2020 or 2021.
Moreover, the experiences of the Argus II recipients could color the reception of future Second Sight products. Doerr notes that his insurer paid nearly $500,000 to implant his device and for training on how to use it.
“What’s the insurance industry going to say the next time this crops up?” Doerr asks, noting that the company’s reputation is “completely shot” with the recipients of its implants.
Perk, who made speeches to praise the Argus II and is still featured in a video on the Second Sight website, says he also no longer supports the company.
Jeroen Perk, an investigator for the Dutch customs service, cried for joy after partially regaining his sight, but he no longer trusts Second Sight, the company that provided his implant.
Nevertheless, Perk remains highly reliant on the technology. When he dropped an external component of his device in late 2020 and it broke, Perk briefly debated whether to remain blind or find a way to get his Argus II working again. Three months later, he was able to revive it by crowdsourcing parts, primarily from surgeons with spare components or other Argus II recipients who no longer use their devices. Perk now has several spare parts in reserve in case of future breakdowns.
Despite the frantic efforts to retain what little sight he has, Perk has no regrets about having the device implanted. And while he no longer trusts Second Sight, he is looking forward to possibly obtaining more advanced implants from companies in the Netherlands and Australia working on their own products.
Doerr suggests that biotech firms whose implants are distributed globally be bound to some sort of international treaty requiring them to service their products in perpetuity. Such treaties are still applied to the salvage rights for ships that sunk centuries ago, he notes.
“I think that in a global tech economy, that would be a good thing,” says McLean, the fellow at Santa Clara, “but I am not optimistic about it in the near term. Business incentives push toward return on share to stockholders, not to patients and other stakeholders. We likely need to rely on some combination of corporately responsibility…and [international] government regulation. It’s tough—the Paris Climate Accord implementation at a slow walk comes to mind.”
Unlike Perk, Doerr has mostly stopped using his Argus II, the result of combination of fear of losing its assistance from wear and tear and disdain for the company that brought it to market. At 70, Doerr says he does not have the time or energy to hold the company more accountable. And with Second Sight having gone through a considerable corporate reorganization, Doerr believes a lawsuit to compel it to better serve its Argus recipients would be nothing but an extremely costly longshot.
“It’s corporate America at its best,” he observes.