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Neurotechnology today: What’s real, what’s coming
A balanced discussion of the realities, the mythologies, and the concerns surrounding cutting-edge brain research.
- A new film, I AM HUMAN, takes a comprehensive look at the realities of neurotechnology today.
- The film follows three patients for whom experimental treatment may be the best option.
- Experts weigh in on the difficulties and the promise of neurotech.
We hear a lot these days about a coming convergence between man and machine. Nowhere are more promises being made than in the area of the brain. From Elon Musk's brain interface to the promise of enhanced minds to home-brewed brain "stimulators," neurotechnology seems poised to carry us across a threshold into a new and glorious world. Or a new and terrifying one. There's robust debate over the potential impact, dangers, and value of such disruptive technology, as there should be. The problem is that we're not so good at thoughtful, reasonable debate.
We don't often write on Big Think about individual movies, but there's a new one, I AM HUMAN, directed and produced by Taryn Southern and Elena Gaby. It provides an unusually intelligent, wide-ranging, and balanced overview of where the research stands, and it's a compelling and thought-provoking experience. This being an area of such keen interest to Big Think readers, we recommend being on the lookout for this film.
Bill, Anne, and Stephen
One of the great hopes for brain research, of course, is that we'll discover the mechanisms behind brain disorders and learn how they can be cured. The World Health Organization has estimated that about 1 in 6 people have a brain disorder of some sort — that's a billion-plus people. As our visionaries fuel our imaginations regarding the eventual possibilities, it's easy to forget there are people here and now for whom the restorative potential of brain technology is no sci-fi daydream — it's a source of hope that their health can be restored. As doctors and technicians embark on this journey, they're accompanied by people you'd never imagine meeting at the cutting edge. People for whom such wildly experimental therapies are their best, and maybe only, hope.
I AM HUMAN introduces us to three such people. It's in following them through their procedures that we see the latest technologies being explored. Our emotional investment in this brave trio viscerally reminds us of the stakes involved.
- Bill recalls, "I was riding a bicycle in a charity event. It was raining really badly and I was following a mail truck. And then all of a sudden, it stopped and I didn't." A tetraplegic, Bill has no feeling below his mid-chest and longs to be able to one day regain enough movement simply to feed himself without assistance.
- Anne has Parkinson's disease. "I'm not really sure what's happening in my brain. Anxiety. Insomnia. Paralysis," says Anne. In addition to her fear of becoming nothing but a burden to her family as her symptoms worsen, "One of the Parkinson's symptoms I was always afraid of was that you couldn't smile and when you smiled you had a stony expression," she says. "It's hard to connect with people. I'm just way too exhausted and way too disorganized mentally to be with people the way I used to."
- Stephen was born with a condition he knew nothing about until his world world turned white: " When I lost my vision, the whole world collapsed." He lives alone, aided by his sister, with whom he's close, helping him get through life. "I just miss being independent."
The challenge of the human brain
Connective ports provide access to electrodes implanted in Bill's brain.
Image source: Luca del Puppo
None of the many experts interviewed in I AM HUMAN believe that a fundamental understanding is imminent of that three-pound object that has so much to do with who we are. Southern tells Big Think that, "The one consistent thing I've learned about a lot of neuroscientists is they have a very sober and humble view of just how complex and difficult of a problem they are tackling."
The current estimate is that the brain contains 100 billions neurons. As neuroscientist Miguel Nicolelis notes, "100 billion was the old estimate of the number of galaxies in the universe." And even that number doesn't convey the true mathematical complexity involved. David Eagleman, also a neuroscientist, says that each of those neurons "is as complicated as the city of Los Angeles. It's connecting to 10,000 of its neighbors — so you have, you know, 500 trillion connections" to identify if you're trying to understand the human brain. Computer scientist Ramez Naam says it simply: "The brain is the most complicated object we've ever encountered in nature."
It's also a black box. Alongside each movement we make are lightning-fast instructions exchanged between these many neurons in some internal language we don't speak. Researchers use a range of technologies to eavesdrop on the brain's chatter — as Southern says, "You have methods like EEG, which uses electrical impulses to read brain activity; deep-brain electrodes also use electricity. But then you've got magnetic resonance imaging (MRI) to read blood flow and sound waves through ultrasound. Of course, the non-invasive methods are more palatable. I'm sure that soon in the future, neuroscientists will see all of our methods now as crude."
Just as daunting, when neuroscientists attempt to manipulate individual neurons, the precision required is astounding, with each procedure a white-knuckle procedure. Surgeon Andres Lozano tells the filmmakers, "This is a game where you have to be within one millimeter. That one millimeter means a difference between success and failure."
Or stumbling into another area of the brain. One doctor told the filmmakers of a case in which an interface was implanted into the hypothalamus of a patient weighing 420 pounds "to see if they could regulate hunger or appetite." No dice. On the other hand, "To their surprise, the patient had vivid flashes of memory from 30 years earlier. When they left the stimulator on for a period of time, at a lower current, the patient had huge increases in memory capacity and being able to remember lists of words."
So for all of the fever-dreams of any-time-now cyber-brains, neurotech investor Bryan Johnson offers a reality check: "It's extraordinarily difficult to make breakthroughs in neuroscience. Scientists are tackling these really complicated problems, trying to do things that other people consider to be impossible. And it makes it both an extremely exciting time but also, it's daunting because there is no clear path to success."
Visions of the neurotech future
Anne must remain conscious during her deep brain surgery.
Image source: Joel Froome, ACS
The film presents' a range of advocates' visions of the possibilities should we finally be able to master the workings of the brain.
"We are about to enter into the most consequential revolution in the history of the human race," says Johnson, "where we can take control of our cognitive evolution. If we can make breakthroughs in the brain, we can overcome our biological limitations. We can reject the things that stop us from moving forward. My hope is that we get to a point in tech advancement that we're not limited by our technology, we're empowered by it, so it's a matter of choice of what we want to become."
While Southern says coverage of research is often focused on the enhancement of people to be "smarter, better, faster," she suggests that this may merely be a reflection of "our own sort-of Western bias to favor productivity and efficiency. But perhaps in other Eastern cultures they would orient the use of an interface to induce greater states of calm or create more empathy."
Johnson offers up how this could work: "Imagine I had a tool to interface with my brain where I could walk a mile in someone else's shoes. What if I could feel what it was like to be you? What if I could understand your contextual framework? What if I understand your memories and your emotions? Would that change the way we deal with each other? The way we cooperate, the way we make decisions?" Or, he adds, "Would that change our creative ability?"
Philosophical question arise
Retinal implants such as Stephen's are created in Second Sight's lab in Sylmar, CA.
Image source: Credit: Joel Froome, ACS
Of course, not everyone is embracing neurotechnology. According to a recent Pew study for example, people are more worried than enthusiastic when it comes to brain chip implants designed to boost a person's natural abilities — only 34% would be interested in getting one. (About half are okay with implants' use for therapeutic value.)
It's not just a fear of change — there are genuine philosophical and ethical issues. As Naam says in the film, "As we have this ability to change who we are, change our personality, what's at the core of us? What does that do to our sense of where we belong in the universe?"
Professor of philosophy and law Nita Farahany sums up the question this way: "If we start tinkering with the brain, if we start changing it….What does that mean? Are we about to fundamentally change what it means to be human? And if so, are we okay with that?" Seeing that, "We're at the moment where there are a lot of very rapidly emerging technologies, and brain computer interfaces are starting to become part of mainstream society,"' she warns that we'd better start figuring out where we want all this research to go before it's too late.
Southern tells us, "My biggest concern around the ethics is the lack of basic knowledge that we have as a society about science and tech. Scientists are so great at science, but sometimes lack the time or ability to connect that information to a larger audience. I think information is power, and the first step is education."
As far as the ethics of experimenting on living patients goes, the decisions of Bill, Anne, and Stephen to participate reflect their lack of better options. "People are worried, you know, 'Will I be the same, coming out, as I was going in?'" says Lozano. "There's a tremendous amount of anxiety about whether they are going to change in their outlook, in their personality, in their motivation, in their drive. You know, this is brain surgery. It's invasive. It is a scary thought."
The doctors involved, says Southern, are "incredibly conscientious about the impact of their work on the world, and those that we worked with on the film have a real drive to help people and improve lives. I don't think many people would argue that restoring function to someone with a disease as a resort of a brain interface is a bad thing. The ethical questions come down the road from there, when adoption becomes more widespread and normalized and people start to seek 'cosmetic' applications of these currently medical devices."
In the end
Southern says she was drawn to this topic as a storyteller. "I see what they're doing, and I think it's just incredible." Her goal in making I AM HUMAN she says, is that, "It's their job to be understated, and my job to hopefully translate the awe and I wonder I feel about what they're doing with the world."
In their experiences creating this film, Southern and Gaby gained a uniquely comprehensive overview of where things stand. We asked Southern what she dreams of humanity gaining from neurotechnology. "I'm really intrigued by the ideas of expanding our sensory abilities and processing. We know that our brains receive data through our given senses — sight, tough, taste, sound, etc. But that data isn't necessarily reflective of reality, and other animals can receive data into their brains differently. For instance, bats have a sense called echolocation that allows them to use sound waves and echoes to determine where they are in space. What if we had that ability? Or what if we could sense electromagnetic waves or ultraviolet light? I'd be pretty excited to see some of these things come to fruition."
Such capabilities could allow us to understand the true nature of physical reality in ways we currently lack the tools to even image. On a more day-to-day level, she adds, "I'd also love to just be able to turn off that pesky and unnecessary fight-or-flight survival response to mundane stress."
The experience has left Southern feeling "Optimistic. Every new technology has been fraught with incredible advantages and drawbacks. I see this being no different. We're just so often uncomfortable with changing the status quo — but ultimately we collectively adopt what is valuable to us. Pessimism around technology," she says, may just reflect issues with our values and systems. "When the foundation of those are broken, it's hard to imagine not building things on top that wreak some degree of havoc. Ultimately, however, having our ability to see and understand the mechanics of our own minds — the creation force of our reality — offers us unparalleled potential beyond our wildest imaginations."
I AM HUMAN will be screened at the Tribeca Film Festival in early May.
"Deepfakes" and "cheap fakes" are becoming strikingly convincing — even ones generated on freely available apps.
- A writer named Magdalene Visaggio recently used FaceApp and Airbrush to generate convincing portraits of early U.S. presidents.
- "Deepfake" technology has improved drastically in recent years, and some countries are already experiencing how it can weaponized for political purposes.
- It's currently unknown whether it'll be possible to develop technology that can quickly and accurately determine whether a given video is real or fake.
After former U.S. President William Henry Harrison delivered his inaugural speech on March 4, 1841, he posed for a daguerreotype, the first widely available photographic technology. It became the first photo taken of a sitting American president.
As for the eight presidents before Harrison, history can see them only through artistic renderings. (The exception is a handful of surviving daguerreotypes of John Quincy Adams, taken after he left office. In his diary, Adams described them as "hideous" and "too true to the original.")
But a recent project offers a glimpse of what early presidents might've looked like if photographed through modern cameras. Using FaceApp and Airbrush, Magdalene Visaggio, author of books such as "Eternity Girl" and "Kim & Kim," generated a collection of convincing portraits of the nation's first presidents, from George Washington to Ulysses S. Grant.
Modern Presidents George Washington https://t.co/CURJQB0kap— Magdalene Visaggio (@Magdalene Visaggio)1611952243.0
What might be surprising is that Visaggio was able to generate the images without a background in graphic design, using freely available tools. She wrote on Twitter:
"A lot of people think I'm a digital artist or whatever, so let me clarify how I work. Everything you see here is done in Faceapp+Airbrush on my phone. On the outside, each takes between 15-30 mins. Washington was a pretty simple one-and-done replacement."
Ulysses S Grant https://t.co/L1IGXLI3Vl— Magdalene Visaggio (@Magdalene Visaggio)1611959480.0
"Other than that? I am not a visual artist in any sense, just a hobbyist using AI tools see what she can make. I'm actually a professional comics writer."
Did another pass at Lincoln. https://t.co/PdT4QVpMbn— Magdalene Visaggio (@Magdalene Visaggio)1611973947.0
Of course, Visaggio isn't the first person to create deepfakes (or "cheap fakes") of politicians.
In 2017, many people got their first glimpse of the technology through a video depicting former President Barack Obama warning: "We're entering an era in which our enemies can make it look like anyone is saying anything at any point in time." The video quickly reveals itself to be fake, with comedian Jordan Peele speaking for the computer-generated Obama.
While deepfakes haven't yet caused significant chaos in the U.S., incidents in other nations may offer clues of what's to come.
The future of deepfakes
In 2018, Gabon's president Ali Bongo had been out of the country for months receiving medical treatment. After Bongo hadn't been seen in public for months, rumors began swirling about his condition. Some suggested Bongo might even be dead. In response, Bongo's administration released a video that seemed to show the president addressing the nation.
But the video is strange, appearing choppy and blurry in parts. After political opponents declared the video to be a deepfake, Gabon's military attempted an unsuccessful coup. What's striking about the story is that, to this day, experts in the field of deepfakes can't conclusively verify whether the video was real.
The uncertainty and confusion generated by deepfakes poses a "global problem," according to a 2020 report from The Brookings Institution. In 2018, the U.S. Department of Defense released some of the first tools able to successfully detect deepfake videos. The problem, however, is that deepfake technology keeps improving, meaning forensic approaches may forever be one step behind the most sophisticated forms of deepfakes.
As the 2020 report noted, even if the private sector or governments create technology to identify deepfakes, they will:
"...operate more slowly than the generation of these fakes, allowing false representations to dominate the media landscape for days or even weeks. "A lie can go halfway around the world before the truth can get its shoes on," warns David Doermann, the director of the Artificial Intelligence Institute at the University of Buffalo. And if defensive methods yield results short of certainty, as many will, technology companies will be hesitant to label the likely misrepresentations as fakes."
Ancient corridors below the French capital have served as its ossuary, playground, brewery, and perhaps soon, air conditioning.
- People have been digging up limestone and gypsum from below Paris since Roman times.
- They left behind a vast network of corridors and galleries, since reused for many purposes — most famously, the Catacombs.
- Soon, the ancient labyrinth may find a new lease of life, providing a sustainable form of air conditioning.
Ancient mining areas below Paris for limestone (red) and gypsum (green).Credit: Émile Gérards (1859–1920) / Public domain
"If you're brave enough to try, you might be able to catch a train from UnLondon to Parisn't, or No York, or Helsunki, or Lost Angeles, or Sans Francisco, or Hong Gone, or Romeless."
China Miéville's fantasy novel Un Lun Dun is set in an eerie mirror version of London. In it, he hints that other cities have similar doubles. On the list that he offhandedly rattles off, Paris stands out. Because the City of Light really does have a twisted sister. Below Paris Overground is Paris Underground, the City of Darkness.
Most people will have heard of the Catacombs of Paris: subterranean charnel houses for the bones of around six million dead Parisians. They are one of the French capital's most famous tourist attractions – and undoubtedly its grisliest.
But they constitute only a small fragment of what the locals themselves call les carrières de Paris ("the mines of Paris"), a collection of tunnels and galleries up to 300 km (185 miles) long, most of which are off-limits to the public, yet eagerly explored by so-called cataphiles.
The Grand Réseau Sud ("Great Southern Network") takes up around 200 km beneath the 5th, 6th, 14th, and 15th arrondissements (administrative districts), all south of the river Seine. Smaller networks run beneath the 12th, 13th, and 16th arrondissements. How did they get there?
Paris stone and plaster of Paris
It all starts with geology. Sediments left behind by ancient seas created large deposits of limestone in the south of the city, mostly south of the Seine; and gypsum in the north, particularly in the hills of Montmartre and Ménilmontant. Highly sought after as building materials, both have been mined since Roman times.
The limestone is also known as Lutetian limestone (Lutetia is the Latin name for ancient Paris) or simply "Paris stone." It has been used for many famous Paris landmarks, including the Louvre and the grand buildings erected during Georges-Eugène Haussmann's large-scale remodelling of the city in the mid-19th century. The stone's warm, yellowish color provides visual unity and a bright elegance to the city.
The fine-powdered gypsum of northern Paris, used for making quick-setting plaster, was so famed for its quality that "plaster of Paris" is still used as a term of distinction. However, as gypsum is very soluble in water, the underground cavities left by its extraction were extremely vulnerable to collapse.
Like living on top of a rotting tooth: subsidence starts far below the surface, but it can destroy your house.Credit : Delavanne Avocats
In previous centuries, a road would occasionally open up to swallow a chariot, or even a whole house would disappear down a sinkhole. In 1778, a catastrophic subsidence in Ménilmontant killed seven. That's why the Montmartre gypsum quarries were dynamited rather than just left as they were. The remaining gypsum caves were to be filled up with concrete.
The official body governing Paris down below is the Inspection Générale des Carrières (IGC), founded in the late 1770s by King Louis XVI. The IGC was tasked with mapping and, where needed, propping up the current and ancient (and sometimes forgotten) mining corridors and galleries hiding beneath Paris.
A delightful hiding place
Also around that time, the dead of Paris were getting in the way of the living. At the end of the 18th century, their final destination consisted of about 200 small cemeteries, scattered throughout the city — all bursting at the seams, so to speak. There was no room to bury the newly dead, and the previously departed were fouling up both the water and air around their respective churchyards.
Something radical had to happen. And it did. From 1785 until 1814, the smaller cemeteries were emptied of their bones, which were transported with full funerary pomp to their final resting place in the ancient limestone quarries at Tombe-Issoire. Three large and modern cemeteries were opened to receive the remains of subsequent generations of Parisians: Montparnasse, Père-Lachaise, and Passy.
The six million dead Parisians in the Catacombs, from all corners of the capital and across many centuries, together form the world's largest necropolis — their now anonymized skulls and bones methodically stacked, occasionally into whimsical patterns. The Catacombs are fashioned into a memorial to the brevity of life. The message above the entrance reads: Arrête! C'est ici l'empire de la Mort. ("Halt! This is the empire of Death.")
That has not stopped the Catacombs, accessible via a side door to a classicist building on the Avenue du Colonel Henri Rol-Tanguy, making just about every Top 20 list of things to see in Paris.
An underground economy
However, while the Catacombs certainly are the most famous part of the centuries-old network beneath Paris, and in non-pandemic times draw thousands of tourists each day, they constitute just 1.7 km (1 mile) of the 300-km (185-mile) tunneling total.
Subterranean Paris wasn't just used for mining and storing dead people. In the 17th century, Carthusian monks converted the ancient quarries under their monastery into distilleries for the green or yellow liqueur that still carries their name, chartreuse.
Because the mines generally keep a constant cool temperature of around 15° C (60° F), they were also ideal for brewing beer, as happened on a large scale from the end of the 17th century until well into the 20th century. Several caves were dug especially for establishing breweries, and not just because of the ambient temperature: going underground allowed brewers to remain close to their customers without having to pay a premium for real estate up top.
Overview of the Paris Catacombs.Credit: Inspection Générale des Carrières, 1857 / Public domain.
At the end of the 19th century, the underground breweries of the 14th arrondissement alone produced more than a million hectoliters (22 million gallons) per year. One of the most famous of Paris' underground breweries, Dumesnil, stayed in operation until the late 1960s.
In that decade, the network of corridors and galleries south of the Seine, long since abandoned by miners, became the unofficial playground for the young people of Paris. They explored the fantastical world beneath their feet, in some cases via entry points located in their very schools. Fascinated, these cataphiles ("catacomb lovers") read up on old books, explored the subterranean labyrinth, and drew up schematics that were passed around among fellow initiates as reverently as treasure maps.
As Robert Macfarlane writes in Underland, Paris-beneath-their-feet became "a place where people might slip into different identities, assume new ways of being and relating, become fluid and wild in ways that are constrained on the surface."
Some larger caves turned into notorious party zones: a 7-meter-tall gallery below the Val-de-Grâce hospital is widely known as "Salle Z." Over the last few decades, various other locations in subterranean Paris have hosted jazz and rock concerts and rave parties — like no other city, Paris really has an "underground music scene."
Hokusai's Great Wave as the backdrop to the "beach" under Paris.Credit: Reddit
Cataphiles vs. cataphobes
With popularity came increased reports of nuisance and crime — the tunnels provided easy access to telephone cables, which were stolen for the resale value of their copper.
The general public's "discovery" of the underground network led the city of Paris to officially interdict all access by non-authorized persons. That decree dates back to 1955, but the "underground police" have an understanding with seasoned cataphiles. Their main targets are so-called tourists, who by their lack of knowledge expose themselves to risk of injuries or worse, and degrade their surroundings, often leaving loads of litter in their wake.
The understanding does not extend to the IGC. Unlike in the 19th century, when weak cavities were shored up by purpose-built pillars, the policy now is to inject concrete to fill up endangered spaces — thus progressively blocking off parts of the network. That procedure has also been used to separate the Catacombs to prevent "infiltration" of the site by cataphiles.
Many subterranean streets have their own names, signs and all. This is the Rue des Bourguignons (Street of the Burgundians) below the Champs des Capucins (Capuchin Field), neither of which exists on the surface.Credit: Jean-François Gornet via Wikimedia and licensed under
The cataphiles, however, are fighting back. In a game of cat and mouse with the authorities, they are reopening blocked passages and creating chatières ("cat flaps") through which they can squeeze into chambers no longer accessible via other underground corridors.
Catacomb climate control
Alone against the unstoppable tide of concrete, the amateurs of Underground Paris would be helpless. But the fight against climate change may turn the subterranean labyrinths from a liability into an asset — and the City of Paris into an ally.
The UN's 2015 Climate Plan — concluded in Paris, by the way — requires the world to reduce greenhouse gas emissions by 75 percent by 2050. And Paris itself wants to be Europe's greenest city by 2030. More sustainable climate control of our living spaces would be a great help toward both targets. A lot of energy is spent heating houses in winter and cooling them in summer.
This is where the constant temperature of the Parisian tunnels comes in. It's not just good for brewing beer; it's a source of geothermal energy, says Fieldwork, an architectural firm based in Paris. It can be used to temper temperatures, helping to cool houses in summer and warming them in winter.
One catch for the cataphiles: it also works when the underground cavities are filled up with concrete. So perhaps one day, Paris Underground, fully filled up with concrete, will completely fall off the map, reducing the city's formerly real doppelgänger into an air conditioning unit.
Cool in summer, warm in winter: Paris Underground could become Paris A/C.Credit: Fieldwork
Strange Maps #1083
Got a strange map? Let me know at email@example.com.
Meconium contains a wealth of information.
- A new study finds that the contents of an infants' first stool, known as meconium, can predict if they'll develop allergies with a high degree of accuracy.
- A metabolically diverse meconium, which indicates the initial food source for the gut microbiota, is associated with fewer allergies.
- The research hints at possible early interventions to prevent or treat allergies just after birth.
The prevalence of allergies arising in childhood has increased over the last 50 years, with 30 percent of the human population now having some kind of atopic disease such as eczema, food allergies, or asthma. The cause of this increase is still subject to debate, though it has been associated with a number of factors, including changes to the gut microbiomes of infants.
A new study by Canadian researchers published in Cell Reports Medicine may shed further light on how these allergies develop in children by examining the contents of their first diaper.
The things you do for science
The research team examined the first stool of 100 infants from the CHILD Cohort Study. The first stool of an infant is a thick, green, horrid-looking substance called meconium. It consists of various things that the infant ingests during the second half of gestation. Additionally, it provides not only a snapshot of what the infant was exposed to during that time, but it also reveals what the food sources will be for the initial gut bacteria that colonize the baby's digestive tract.
The content of the meconium was examined and found to contain such varied elements as amino acids, lipids, carbohydrates, and myriad other substances.
A graph of the comparative, summed abundance of different elements in a metabolic pathway after scaling to median abundance of each metabolite. The blue figures are those children without atopy, the yellow ones show the data for those with an atopic condition. Petersen et al.
The authors fed this information into an algorithm that used this data, along with the identities of the bacteria present as well as the baby's overall health, to predict which infants would go on to develop allergies within one year. The algorithm got it right 76 percent of the time.
A way to prevent childhood allergies?
Infants whose meconium had a less diverse metabolic niche the initial microbes to settle in the gut were at the highest risk of developing allergies a year later. Many of these elements were associated with the presence or absence of different bacterial groups in the digestive system of the child, which play an increasingly appreciated role in our overall health and development. The findings were summarized by senior co-author Dr. Brett Finlay:
"Our analysis revealed that newborns who developed allergic sensitization by one year of age had significantly less 'rich' meconium at birth, compared to those who didn't develop allergic sensitization."
The findings could be used to help understand how allergies form and even how to prevent them. Co-author Dr. Stuart Turvey commented on this possibility:
"We know that children with allergies are at the highest risk of also developing asthma. Now we have an opportunity to identify at-risk infants who could benefit from early interventions before they even begin to show signs and symptoms of allergies or asthma later in life."
A model for early childhood allergies
Petersen et al.
As shown above, the authors constructed a model of how they believe metabolites and bacterial diversity help prevent allergies. Increased diversity of metabolic products in the meconium encourage the development of "healthy" families of bacteria, like Peptostreptococcaceae, which in turn promote the development of a healthy and diverse gut microbiome. Ultimately, such diversity decreases the likelihood that a child will develop allergies.