SEBASTIAN JUNGER: The internet is sort of this crazy amazing and sometimes sort of bullying environment. In a way it's an exciting and a dangerous place. Because of the internet we can all of us now with a few clicks can watch video of incredible atrocities being committed against other people. That's new in human experience. I mean usually if you're watching someone's head get cut off you're in a situation where you're either part of that and you have some moral responsibility or your own head is about to get cut off. But either way your body goes into a sort of fight or flight reaction which is programmed by hundreds of thousands of years of evolution. When you see violence your body is ready, readies itself to deal with violence.
So now what we can do is watch violence from the safety of our couch. Our body doesn't know we're sitting on our couch. The moral debate in our minds isn't engaged the way it is when someone's head is actually getting cut off in front of you. That has real consequence psychologically for people and personally I just don't watch anything online that I wouldn't be okay with seeing in person. Seeing violence up close and personally I know the effect that it's had on my psyche, on me as a person and I don't want it. I just don't watch it. And I do worry about young people who have access to this. It has to be harming them and we haven't had the internet long enough to see how that harm will play out through the course of someone's life.
- "The internet is an exciting and a dangerous place," says journalist and documentarian Sebastian Junger.
- He argues that because of thousands of years of evolution, our bodies react to seeing decapitations on screens as if they were happening in front of or to us.
- According to Junger, the internet is too new for us to really understand the long-term effects it will have on our lives.
- Counteracting the Violent Media Effect: The Media Can Inspire Us to ... ›
- Why We Love Violence In Fiction - Big Think ›
In February 2021, Josh was in his room and looking at his phone when he was struck by a strange feeling.
"The room looked normal, nothing was moving, but I felt as though I was under the influence of a psychedelic," he told Big Think. As a teenager, Josh had experimented with LSD, mushrooms, and other psychedelics a couple dozen times. Now 25, he had been sober for about a year. He brushed off the incident.
But soon, Josh, which is not his real name, was struck again by the same strange feeling.
"I had no idea what was going on in my brain at that time and the anxiety and paranoia grew so intense that I became fearful I had developed everything from brain cancer to schizophrenia," he said. The physical and psychological symptoms he began suffering were "devastating."
"The world [looked] crooked and out of focus, pictures had an eerie quality to them, things would go in and out of focus, at night while falling asleep I would experience vivid and terrifying hypnagogic hallucinations that made rest impossible."
After three weeks, Josh said his visual symptoms amplified with "unbelievable intensity."
"The floors would [breathe], paint on the walls looked wet, visual snow was so intense [that] pure black looked like it was glowing, at night I would see tracers everywhere, halos appeared around text. [...] I did not sleep, my thoughts were anxious and at times deranged, I had unbelievably intense dereliction that made the world seem fake."
LSD flashbacks
What Josh experienced is commonly called an LSD flashback. It's a mysterious phenomenon in which someone who's previously taken a hallucinogenic drug suddenly and temporarily experiences the effects of that drug days, weeks, or even years after consuming it.
Flashbacks can occur after taking a wide range of psychedelic drugs. But compared to other hallucinogens, flashbacks seem to be most common among people who have consumed LSD, according to studies
Antique old clock abstract fractal spiral
Antique old clock abstract fractal spiralNewwup via Adobe Stock
People have reported acid flashbacks for decades. The earliest recorded case may be Havelock Ellis' 1898 report of taking mescaline and then experiencing sustained heightened sensitization to "the more delicate phenomena of light and shade and color."
But it wasn't until the 1950s, little more than a decade after Albert Hoffman first synthesized LSD, that scientists started researching LSD and its potential long-term effects. While studies have illuminated some aspects of how psychedelics affect the brain, scientists still have much to learn about the nature of acid flashbacks, what causes them, and how to treat them.
What's certain, however, is that a small percentage of people who consume psychedelics report bizarre and sometimes debilitating effects that emerge long after taking hallucinogens.
Symptoms of acid flashbacks
Among the most common symptoms of LSD flashbacks are visual distortions. In a 1983 study titled "Visual Phenomenology of the LSD Flashback," the psychiatrist and LSD researcher Dr. Henry David Abraham described 16 common visual disturbances reported by people with LSD flashbacks. To name a few:
- Acquired color confusion: The color of objects changed or presented a newly discovered problem of color confusion.
- Difficulty reading: Text may appear jumbled or leave afterimages of the type against the background of the page.
- Geometric phosphenes: Phosphenes, or eigengrau, are non-specific luminous perceptions that occur when the eyes are closed and may originate from entopic (i.e., arising from within the eye itself) stimuli in normal persons. They also may be induced by gentle pressure on the closed eyelid.
- Pareidolias: This is literally an image within an image. These were described when a subject gazed into a finely reticulated design in linoleum, veneer, or a cloud formation. Besides the abstract pattern of the linoleum, subjects often would be able to see a series of concrete images as well, such as "a fish," "a face," and "a little boy."
- Macropsia: Macropsia is the perception of an object larger than it really is. A characteristic description of this phenomenon came from a subject who noticed that his hand was enormous and then of normal size a few seconds later.
- Micropsia: Micropsia is the perception of an object smaller than reality. One subject said, "My feet looked so tiny, like they were a million miles away."
The effects of acid flashbacks aren't limited to visual distortions. In a 1970 study called "Analysis of the LSD Flashback," researchers sorted LSD flashbacks into three broad categories: perceptual, somatic (meaning of the body), and emotional.
The emotional flashback is "far more distressing" than the other two, the researchers wrote, providing a case study of a 21-year-old woman who was suffering from acid flashbacks:
"The patient had these frightening flashbacks during the day, while walking down the street, after smoking marijuana or drinking wine, during the night, and occasionally even while asleep. In one situation she awoke during the middle of the night with a feeling of panic and began running around her house fleeing an imagined threat she could not identify or comprehend. She had taken LSD a number of times, but her last few trips were bad ones with panic and fright followed by loneliness to the point of suicidal despair when she 'came down.' The combination of bad trips and emotional flashbacks made her seek professional help because of her fear that she would harm herself."
To be sure, acid flashbacks aren't always emotionally distressing. A 2010 survey of 600 hallucinogen users found that, of the minority of users who reported experiencing at least one flashback, only 3 percent described it as a negative experience. In fact, some people enjoyed their flashbacks. On the website Erowid, which promotes research of psychedelic drugs, one user wrote:
"After 2 years of my last acid trip, while on vacation in a very nice wilderness place I was sitting on a rock and then I experienced a clear acid high. I was looking at a very steep hill and suddenly it started moving in nice patterns, exactly as one sees patterns while on acid. It wasn't something uncomfortable. In fact it was really pleasant and there was absolutely no trace of the nasty anxiousness after effects common to LSD. It lasted approximately 2 minutes and I enjoyed it very much."
But some LSD flashbacks are neither brief nor pleasant. A subset of people who use psychedelics develop hallucinogen persisting perception disorder (HPPD), a rare and poorly understood condition in which people experience omnipresent or recurring flashbacks. While the symptoms of HPPD vary, the condition can cause intense pain, irreversible perceptual distortions, emotional and psychological distress, and even suicidal thoughts.
HPPD: The never-ending trip
HPPD is estimated to affect between one to five percent of LSD users, though the actual figure is impossible to determine without better data. The disorder was first described formally in 1986 by the American Psychiatric Association's Diagnostic & Statistical Manual of Mental Disorders, 3rd edition, revised (DSM-III-R). The current edition of the manual (DSM-5) says patients need to meet several criteria to be diagnosed with HPPD:
- Patients must reexperience perceptual symptoms they experienced while intoxicated with the hallucinogen.
- These symptoms must cause "significant distress or impairment in social, occupational, or other important areas of functioning."
- These symptoms aren't due to a separate medical condition or mental disorder.
So, what's the difference between a flashback and HPPD? Mainly frequency and duration. A 2017 review published in Frontiers in Psychiatry noted that while "a flashback is usually reported to be infrequent and episodic, HPPD is usually persisting and long-lasting."
A 2014 review published in the Israel Journal of Psychiatry and Related Sciences outlined two types of HPPD. The first, HPPD I, is the "flashback type," which is a generally short-term, non-distressing, benign and reversible state accompanied by a pleasant affect. The severity of HPPD I varies, with some people describing their mild flashbacks as annoying, while others say it's like getting "free trips."
But HPPD II is a different beast. The condition can be permanent, with perceptual distortions and other symptoms manifesting irregularly or almost constantly. "The symptoms usually include palinopsia (afterimages effects), the occurrence of haloes, trails, akinetopsia, visual snows, etc.," according to the aforementioned 2017 review. "Sounds and other perceptions are usually not affected. Visual phenomena have been reported to be uncontrollable and disturbing. Symptomatology may be accompanied by depersonalization, derealization, anxiety, and depression."
What causes flashbacks and HPPD?
When asked what causes flashbacks and HPPD, Dr. Abraham told Popular Science, "I've spent my life studying this problem and I don't know, is the short answer."
But researchers have proposed explanations. One centers on memory. Because psychedelics can cause extremely powerful and emotional experiences, it's theoretically possible that certain environmental stimuli can remind people of those experiences, and then memory "transports" them back into that subjective mindset — similar to how a soldier with post-traumatic stress disorder might suffer an episode after hearing a loud, sudden noise.
Another hypothesis involves how LSD interacts with the brain's visual processing center. Dr. Abraham proposed that HPPD may arise due to "disinhibition of visual processing related to a loss of serotonin receptors on inhibitory interneurons," which may be caused by consuming LSD.
The basic idea is that LSD somehow changes the way the brain interprets visual stimuli. That might explain why people with HPPD have difficulty properly "disengaging" from the things they see around them. For example, a red stoplight might appear as a discrete red circle but as a streak of red light painted across their field of vision; or a strobe light might not appear as a flickering light but a light that's constantly on.
LSD on paperYurok Aleksandrovich via Adobe Stock
"Such a locking of visual circuitry into an 'on' position following perception of a visual stimulus would explain such diverse complaints as trailing, color intensification, positive afterimages, phosphenes, and color confusions, each of which may represent a failure of the respective visual function to turn off the brain's response to the stimulus once the stimulus is gone," Dr. Abraham wrote.
It's also possible that people are genetically predisposed to HPPD and that ingesting LSD is the key that unlocks the disorder. This hypothesis would help explain why people have reportedly developed HPPD after taking a single, moderate dose of LSD.
Ultimately, the exact causes of HPPD are unclear. Partially as a result, there's currently no cure for the disorder, though studies show that people with HPPD have reported improvements in symptomatology after taking benzodiazepines. There's also anecdotal evidence that fasting can alleviate the disorder.
Despite uncertainty over the causes of HPPD, researchers do have a good idea of what can trigger "flare-ups" of HPPD. Dr. Abraham's 1983 study listed the most common triggers, some of which include:
- Emergence into a dark environment
- Intention (intentionally inducing visual aberrations by, say, staring at a blank wall)
- Marijuana
- Phenothiazines
- Anxiety
- Fatigue
People with HPPD describe the condition
To get a better understanding of HPPD, Big Think posted a questionnaire to the HPPD community on Reddit. Here are some of the responses:
How did HPPD first manifest for you?
IBeatMyGlied wrote:
"First I noticed highly enhanced creativity and intense visuals when [high on] weed and I really enjoyed that part. The realization that this is not going to go away soured the whole experience tho."
"My enhanced creativity left me after about a week and what I was left with was mild visual snow. I hardly knew anything about HPPD at the time and just didn't really care about my symptoms and still thought they were just going to vanish at some point, which they didn't. I kept taking drugs simply because I was addicted and felt like life is no fun without them. My HPPD got gradually worse over time and more symptoms appeared. First, I noticed mild tracers, which got worse over time (again due to continued drug use) and then tinnitus and brain fog. But primarily my symptoms are visual."
Are your symptoms episodic or constant?
"Both constant and episodic," wrote user LotsOfShungite. "A stressful event can trigger my symptoms off into the deep end."
Halven89 wrote:
"Except the brain fog and head pressure that varies, my visual disturbances are constant. The most debilitating ones are the visual snow, especially when I'm inside except if I watch the TV since it filters some of it out. It's also VERY frustrating that I no longer can focus on objects/details (can't stare) and the astigmatism-like symptoms that I got, like blurriness, especially in the distance and ghosting (double vision) plus starbursts from strong light sources. When I'm outside, the pattern glare is really annoying, same with the excessive amount of floaters that came with this. I also see halos from light sources."
IBeatMyGlied wrote:
"My symptoms are mostly constant and only change through rather obvious outside influences, such as certain drugs (almost all drugs), stress, lack of sleep, etc. Although my HPPD is quite pronounced, I have learned to accept it and almost only notice it when I pay attention to it. I always [know] it's there and it somewhat bugs me but I get along."
What are some common misconceptions about HPPD?
IBeatMyGlied wrote:
"One of if not the biggest 'misconception' is that many people believe that HPPD does not exist. But I guess there is no way to prove to another person that it does, so this is gonna stay the case until HPPD enters the public consciousness of the psychedelic community."
Halven89 wrote:
"They usually don't understand anything about it since most haven't heard about it, which really is crazy considering how debilitating this disorder is for many. And as Dr. Abraham said: in the medical field it's highly under- and misdiagnosed. Often as psychosis."
Futuristic view from inside of a fractalLopyriev via Adobe Stock
Hope for HPPD
Since experiencing his first flashback in February, Josh has found a few helpful strategies to minimize symptoms, including seeing a psychologist, staying sober, getting enough sleep, staying productive, and talking regularly with friends. He seemed optimistic about the future:
"The symptoms will lessen with time and sobriety, and HPPD provides an opportunity to improve yourself. That being said, because thoughts of suicide are apparently common with people that have HPPD, the medical community should take the condition seriously. Especially given how many people use psychedelics today."
While the future of HPPD research remains unclear, general psychedelic research is going through something of a renaissance. In recent years, researchers have published a growing body of studies showing how psychedelics like psilocybin, LSD, and MDMA can help treat conditions like depression, anxiety, post-traumatic stress disorder, and existential distress. But, among people with HPPD, opinions on the utility of psychedelics vary. Josh advised caution:
"I would not recommend [hallucinogenic] drugs be taken for recreational purposes. They are tools to help us treat illnesses and should be treated as such. If someone has depression or other mental health issue, maybe psychedelics administered in a clinical setting by a doctor is appropriate, but otherwise, playing with your brain like it's a chemistry playset is asking for trouble down the road."
The field of neurotheology continues to expand from its early origins several decades ago to the present day. In its simplest definition, neurotheology refers to the field of scholarship that seeks to understand the relationship between the brain and our religious and spiritual selves. As I always like to say, it is important to consider both sides of neurotheology very broadly. Thus, the "neuro" side includes brain imaging, psychology, neurology, medicine, and even anthropology. And the "theology" side includes theology itself, but also various aspects related to religious beliefs, attitudes, practices, and experiences.
The mental health benefits of spirituality
Neurotheology also ranges from considering very esoteric concepts including questions around free will, consciousness, and the soul, to very practical concepts such as understanding how the brain functions and the relationship between spirituality and physical and mental health. This latter topic might be called "applied neurotheology." Applied neurotheology, therefore, seeks to understand the health-related aspects pertaining to our brain and our spiritual selves. In particular, we can try to understand how being religious or spiritual, or performing various spiritual practices, might be beneficial to our overall health and well-being. In our latest book, entitled Brain Weaver, we consider this important dimension of human brain health.
Even for those who are not religious, pursuing practices such as meditation and prayer — even when secularized — can be beneficial for reducing stress and anxiety.
A growing number of studies have shown how spirituality and mental health are linked. Importantly, studies have shown that those who are religious and spiritual tend to have lower rates of depression, anxiety, and suicide. This is true across the age spectrum with studies of adolescents showing that religious and spiritual pursuits are protective against mental health problems. And many adults cite religious and spiritual beliefs as important for coping with various life stressors.
Indirect mechanisms
Credit: MOHAMMED SAWAF via Getty Images
If there is a relationship between spirituality and positive mental health, we might question what the mechanism of action might be. I have typically divided the mechanisms into indirect and direct ones. The indirect mechanisms have to do with specific aspects of a given tradition that end up having ancillary mental health benefits. For example, going to church or other social events that are part of a religious tradition can be beneficial because social support, in and of itself, is beneficial to our mental health. The more people that we have in our social support network, the better we are at coping with various life stressors including problems with jobs, relationships, or health.
Most religions also teach people to avoid a lot of high-risk behaviors that can be very detrimental to our mental health and well-being. For example, most religions teach us to avoid alcohol and drugs, to not be promiscuous, and to try to be compassionate and charitable to others. By following these teachings, people will naturally avoid mental health problems such as substance abuse and tend toward being more optimistic and less depressed. These effects have nothing to do with being religious per se and everything to do with following a religion's advice.
Another interesting indirect mechanism of action related to religion has to do with diet and nutrition. Diet and nutrition are frequently overlooked when it comes to good mental health, even though research increasingly indicates they are essential. Many traditions ask individuals to follow certain dietary guidelines. For example, Hindus tend to have vegetarian diets, and most research to date shows that eating a more plant-based diet with a lot of low-inflammatory foods is good not only for your body but for your brain as well. In fact, we are currently performing a study with patients who have chronic concussion symptoms to determine the effect of dietary improvements on overall brain function.
Direct mechanisms
Credit: MIGUEL MEDINA via Getty Images
The direct mechanisms of action have to do with specific spiritual practices and even a person's personal sense of spirituality. Much of my research over the past 30 years has been to study the brain while people engage in different practices such as meditation or prayer. We have even observed brain changes associated with unique spiritual practices such as speaking in tongues or trance states. The brain effects related to these practices are quite remarkable and diverse. It should come as no surprise since these practices affect people on many different levels, such as the way people think, feel, and experience the world around them. Thus, we should expect to observe physiological differences in the parts of the brain involved with these practices.
Meditation and prayer, for example, activate the frontal lobes as well as the language areas of the brain, and research demonstrates that this occurs not only while the practice is performed but over the long-term as well. Our study of Kirtan Kriya meditation showed improvements of about 10 to 15 percent in cognition as well as reductions in stress, anxiety, and depression. These were associated with baseline changes to the brain's frontal lobe functions, which regulate these cognitive processes and modulate emotional responses.
More recent research has been exploring the effects of these practices on larger brain networks, and perhaps more important, specific neurotransmitter systems. One of our recent studies of a spiritual retreat program showed significant changes to the areas of the brain that release dopamine and serotonin. These are areas known to be involved in both cognition and emotional health. And there are a growing number of clinical studies which have documented the value of various spiritual practices or religiously oriented therapies for helping people manage a variety of mental health conditions including depression, anxiety, and ADHD as well as neurological conditions like Alzheimer's and seizure disorders.
Credit: JEAN-FRANCOIS MONIER via Getty Images
Finally, a personal sense of spirituality may be protective in and of itself. When people feel connected to all of humanity, a higher power, or the entire universe, that experience gives people a sense of meaning and purpose in life and an optimistic perspective on what the future holds. A number of research studies have shown that having such faith can be beneficial to your overall physical and mental health.
Improving brain health with applied neurotheology
Applied neurotheology can teach us the value of exploring our religious and spiritual side as a way of improving our mental health and well-being. Even for those who are not religious, pursuing practices such as meditation and prayer — even when secularized — can be beneficial for reducing stress and anxiety. Connecting with the larger world — by going on a nature walk, socializing with friends and family, or trying to make your neighborhood a better place by helping others — leads to a greater sense of compassion and love, positive emotions that will make your brain healthier.
Dr. Andrew Newberg is a neuroscientist who studies the relationship between brain function and various mental states. He is a pioneer in the neurological study of religious and spiritual experiences, a field known as "neurotheology." His latest book is Brain Weaver.
The asteroid 2021 PDC was first spotted on April 19, 2021 by the Pan-STARRS project at the University of Hawaii. By May 2, astronomers were 100% certain it was going to strike Earth somewhere in Europe or northern Africa. On October 20, 2021, the asteroid plowed into Europe, taking countless lives.
There was absolutely nothing anyone could do to deflect it from its deadly course. Experts could only warn a panicking population to get out of the way as soon as possible, if it was possible.
The above scenario is the result of a recently concluded NASA thought experiment.
The question the agency sought to answer was this: If we discovered a potentially deadly asteroid destined to hit Earth in six months, was there anything we could do to prevent a horrifying catastrophe? The disturbing answer is "no," not with currently available technology.
While Europe can breathe easy for now, the simulation conducted by NASA/JPL's Center for Near Earth Object Studies and presented at the 7th IAA Planetary Defense Conference is troubling. Space agencies spot "near-Earth objects" (NEOs) all the time. Many are larger than 140 meters in size, which means they're potentially deadly.
Sitting Ducks
Credit: ImageBank4U / Adobe Stock
"The level [at] which we're finding the 140-meter and larger asteroids remains pretty stable, at about 500 a year. Our projection of the number of these objects out there is about 25,000, and we've only found a little over one-third of those so far, maybe 38% or so," NASA's Planetary Defense Office Lindley Johnson tells Space.com.
With our current technology, spotting an NEO comes down to whether we just happen to have a telescope pointing in its direction. To remove humanity's blind spot, the Planetary Society — the same organization that deployed Earth's first light sails — is developing the NEO Surveyor spacecraft, which they plan to deploy in 2025. According to the Planetary Society, it will be able to detect 90 percent of NEOs of 140 meters or larger, a vast improvement.
How to move an asteroid
The DART spacecraft will attempt to deflect an asteroid.Credit: NASA
The NASA/JPL exercise made clear that six months is just not enough time with our current technology to prepare and launch a mission in time to nudge an NEO off its course. (Small course adjustments become significant over great distances, which is why "nudging" an asteroid is a potential strategy.)
What would such a mission look like? Hollywood aside — remember Armageddon?— we know of no good way to redirect an NEO headed our way. Experts believe that shooting laser beams at an incoming rock, exciting as it might look, is not a realistic possibility. Targeted nuclear blasts might work, but forget about landing Bruce Willis, Ben Affleck, and Liv Tyler on an asteroid to set off a course-altering bomb, especially just a month after its discovery (as was the case in the movie).
Another thing that might work is crashing a spacecraft into an NEO hard enough to shift its course. That's the idea behind NASA's Double Asteroid Redirection Test (DART). This mission will shoot a spacecraft at the (non-threatening) asteroid Dimorphos in the fall of 2022 in the hope of changing its trajectory.
The deadly asteroid's journey
The asteroid "2021 PDC" hit Europe in NASA's simulation.Credit: NASA/JPL
The harrowing "tabletop exercise," as NASA/JPL called it, took place across four days at the conference:
- Day 1, "April 19" — The asteroid named "2021 PDC" is discovered 35 million miles away. Scientists calculate it has a 1-in-20 chance of striking Earth.
- Day 2, "May 2" — Now certain that 2021 PDC will hit Earth, space mission designers attempt to dream up a response. They conclude that with less than six months to impact, there's not enough time to realistically mount a mission to disrupt the NEO's course.
- Day 3, "June 30" — Images from the world's four largest telescopes reveal the area in Europe that will be hit. Space-based infrared measurements narrow the object's size to between 35 and 700 meters. This would pack a similar punch as a 1.2-megaton nuclear bomb.
- Day 4, "October 14" — Six days before impact, the asteroid is just 6.3 million km from Earth. Finally, the Goldstone Solar System Radar has been able to assess the size of 2021 PDC. Scientists calculate the blast from the asteroid will be primarily confined to the border region between Germany, Czechia, Austria, Slovenia, and Croatia. Disaster response experts develop plans for addressing the human toll.
"Each time we participate in an exercise of this nature," says Johnson, "we learn more about who the key players are in a disaster event, and who needs to know what information, and when."
Practically speaking, little can be done to hurry technological development along other than budgeting more money toward that goal. Maybe we should have Bruce Willis on call, just in case.
In the novel, technicians in charge of the hatcheries manipulate the nutrients they give the fetuses to make the newborns fit the desires of society. Two recent scientific developments suggest that Huxley's imagined world of functionally manufactured people is no longer far-fetched.
On March 17, 2021, an Israeli team announced that it had grown mouse embryos for 11 days – about half of the gestation period – in artificial wombs that were essentially bottles. Until this experiment, no one had grown a mammal embryo outside a womb this far into pregnancy. Then, on April 15, 2021, a U.S. and Chinese team announced that it had successfully grown, for the first time, embryos that included both human and monkey cells in plates to a stage where organs began to form.
As both a philosopher and a biologist I cannot help but ask how far researchers should take this work. While creating chimeras – the name for creatures that are a mix of organisms – might seem like the more ethically fraught of these two advances, ethicists think the medical benefits far outweigh the ethical risks. However, ectogenesis could have far-reaching impacts on individuals and society, and the prospect of babies grown in a lab has not been put under nearly the same scrutiny as chimeras.
Mouse embryos were grown in an artificial womb for 11 days, and organs had begun to develop.
Growing in an artificial womb
When in vitro fertilization first emerged in the late 1970s, the press called IVF embryos “test-tube babies," though they are nothing of the sort. These embryos are implanted into the uterus within a day or two after doctors fertilize an egg in a petri dish.
Before the Israeli experiment, researchers had not been able to grow mouse embryos outside the womb for more than four days – providing the embryos with enough oxygen had been too hard. The team spent seven years creating a system of slowly spinning glass bottles and controlled atmospheric pressure that simulates the placenta and provides oxygen.
This development is a major step toward ectogenesis, and scientists expect that it will be possible to extend mouse development further, possibly to full term outside the womb. This will likely require new techniques, but at this point it is a problem of scale – being able to accommodate a larger fetus. This appears to be a simpler challenge to overcome than figuring out something totally new like supporting organ formation.
The Israeli team plans to deploy its techniques on human embryos. Since mice and humans have similar developmental processes, it is likely that the team will succeed in growing human embryos in artificial wombs.
To do so, though, members of the team need permission from their ethics board.
CRISPR – a technology that can cut and paste genes – already allows scientists to manipulate an embryo's genes after fertilization. Once fetuses can be grown outside the womb, as in Huxley's world, researchers will also be able to modify their growing environments to further influence what physical and behavioral qualities these parentless babies exhibit. Science still has a way to go before fetus development and births outside of a uterus become a reality, but researchers are getting closer. The question now is how far humanity should go down this path.
Chimeras evoke images of mythological creatures of multiple species – like this 15th-century drawing of a griffin – but the medical reality is much more sober. (Martin Schongauer/WikimediaCommons)
Human-monkey hybrids
Human–monkey hybrids might seem to be a much scarier prospect than babies born from artificial wombs. But in fact, the recent research is more a step toward an important medical development than an ethical minefield.
If scientists can grow human cells in monkeys or other animals, it should be possible to grow human organs too. This would solve the problem of organ shortages around the world for people needing transplants.
But keeping human cells alive in the embryos of other animals for any length of time has proved to be extremely difficult. In the human-monkey chimera experiment, a team of researchers implanted 25 human stem cells into embryos of crab-eating macaques – a type of monkey. The researchers then grew these embryos for 20 days in petri dishes.
After 15 days, the human stem cells had disappeared from most of the embryos. But at the end of the 20-day experiment, three embryos still contained human cells that had grown as part of the region of the embryo where they were embedded. For scientists, the challenge now is to figure out how to maintain human cells in chimeric embryos for longer.
Regulating these technologies
Some ethicists have begun to worry that researchers are rushing into a future of chimeras without adequate preparation. Their main concern is the ethical status of chimeras that contain human and nonhuman cells – especially if the human cells integrate into sensitive regions such as a monkey's brain. What rights would such creatures have?
However, there seems to be an emerging consensus that the potential medical benefits justify a step-by-step extension of this research. Many ethicists are urging public discussion of appropriate regulation to determine how close to viability these embryos should be grown. One proposed solution is to limit growth of these embryos to the first trimester of pregnancy. Given that researchers don't plan to grow these embryos beyond the stage when they can harvest rudimentary organs, I don't believe chimeras are ethically problematic compared with the true test–tube babies of Huxley's world.
Few ethicists have broached the problems posed by the ability to use ectogenesis to engineer human beings to fit societal desires. Researchers have yet to conduct experiments on human ectogenesis, and for now, scientists lack the techniques to bring the embryos to full term. However, without regulation, I believe researchers are likely to try these techniques on human embryos – just as the now-infamous He Jiankui used CRISPR to edit human babies without properly assessing safety and desirability. Technologically, it is a matter of time before mammal embryos can be brought to term outside the body.
While people may be uncomfortable with ectogenesis today, this discomfort could pass into familiarity as happened with IVF. But scientists and regulators would do well to reflect on the wisdom of permitting a process that could allow someone to engineer human beings without parents. As critics have warned in the context of CRISPR-based genetic enhancement, pressure to change future generations to meet societal desires will be unavoidable and dangerous, regardless of whether that pressure comes from an authoritative state or cultural expectations. In Huxley's imagination, hatcheries run by the state grew a large numbers of identical individuals as needed. That would be a very different world from today.
Sahotra Sarkar, Professor of Philosophy and Integrative Biology, The University of Texas at Austin College of Liberal Arts
This article is republished from The Conversation under a Creative Commons license. Read the original article.
