Big Think's Top 25 +1 Videos


Mama, Don't Let Your Babies Grow Up To Deny Evolution

If adults want to deny evolution, sure. That’s fine. Whatever. But those adults better not make their kids follow in step because we as society need them to be better. Bill Nye, everyone's favorite Science Guy, explains the importance of promoting evolution education for America's future voters and lawmakers.

My Man, Sir Isaac Newton

Are you at least 26 years-old? If so, you are older than Isaac Newton was when he invented calculus... on a dare! (If you're younger than 26, better hurry up.) Big Think expert and overall cool guy Neil deGrasse Tyson explains why Newton is the greatest physicist who ever and likely will ever live.

Will Mankind Destroy Itself?

Theoretical physicist Michio Kaku sees two major trends today. One eventually leads to a multicultural, scientific, tolerant society that will expand beyond Earth in the name of human progress. The other trend leads to fundamentalism, monoculturalism, and -- eventually -- civilizational ruin. Whichever of these two trends wins out will determine the fate of mankind. No pressure, everyone.

Ricky Gervais on the Principles of Comedy

Comedy isn't just about making people laugh, says actor Ricky Gervais. It's about making people think. And while different forms of comedy require different approaches, the crux of any good performance will always be rhythm.

Reading the Bible (Or the Koran, Or the Torah) Will Make You an Atheist

Author and magician Penn Jillette was asked to leave his Christian youth group by a pastor who told his parents: "He's no longer learning about the Bible from me. He is now converting everyone in the class to atheism." The reason? Jillette did his homework and was turned off by the hostilities of the text. It can be intimidating to come out as an atheist, especially in a religious community. Jillette found that having "out" atheist role models helped him feel unalone.

Henry Rollins: The One Decision that Changed My Life Forever

Punk legend Henry Rollins describes the biggest turning point in his life: the moment he decided to leave his job as manager of a Häagen-Dazs store and eventually become the lead singer of Black Flag. It was the courage to take a risk, plus a whole lot of luck, that got Rollins to where he is today.

5 Programming Languages Everyone Should Know

Java is "heavyweight, verbose, and everyone loves to hate it," but programmer Larry Wall still thinks you should know it. In this video, he offers suggestions for people interested in learning languages, as well as suggestions for those significantly less invested in computer programming.

The Importance of Unbelief

If you assume there’s no afterlife, Stephen Fry says, you’ll likely have a fuller, more interesting "now" life. The actor and comedian details the positive influence philosophers have had on his life, as well as his journey of understanding both what he believes and why he believes it.

Why be happy when you could be interesting?

We don't really want what we think we desire, says philosopher Slavoj Žižek.

James Gleick on the Common Character Traits of Geniuses

This video is part of a series on female genius, in proud collaboration with 92Y's 7 Days of Genius Festival.


The personalities of Isaac Newton and Richard Feynman were, on one level, extremely different. Biographer and former New York Times reporter James Gleick says Newton was argumentative, had few friends, and likely died a virgin. Feynman, on the other hand, loved dancing and going to parties, and had many friends in the scientific community. But in regards to their working habits, both men were solitary and had the ability to concentrate with a sort of intensity that is hard for mortals to grasp. At bottom, Gleick says geniuses tend to have a yearning for solitude which, though fruitful for their professional work, made the task of daily living more burdensome.

The Importance of Doing Useless Things

From poetry and ballet to mathematics and being clever, life is laden with frivolous pursuits that hold no bearing on our ability to survive. Yet, insists Richard Dawkins, if it weren’t for the development of these impractical activities, we wouldn’t be here.

Why monogamy is ridiculous

Dan Savage: the idea that one instance of infidelity should ruin a relationship is a new—and misguided—notion.

Dan Harris: Hack Your Brain's Default Mode With Meditation

Dan Harris explains the neuroscience behind meditation, but reminds us that the ancient practice isn't magic and likely won't send one floating into the cosmic ooze. He predicts that the exercise will soon become regularly scheduled maintenance, as commonplace as brushing your teeth or eating your veggies. Harris, an ABC News correspondent, was turned on to mediation after a live, on-air panic attack. His latest book is 10% Happier: How I Tamed the Voice in My Head, Reduced Stress Without Losing My Edge, and Found Self-Help That Actually Works--A True Story.

How Intellectuals Betrayed the Poor

For 40 years academics were duped into idolizing the idea of unfettered markets, says Cornel West, and now our society is paying a terrible price.

Why Some Races Outperform Others

A psychologist explains the latest research into education disparity.

Why It's So Hard for Scientists to Believe in God

Some scientists see religion as a threat to the scientific method that should be resisted. But faith "is really asking a different set of questions," says Collins.

Why Facebook Isn't Free

Internet pioneer Jaron Lanier argues that free technologies like Facebook come with a hidden and heavy cost – the livelihoods of their consumers.

How to Tell if You’re a Writer

For John Irving, the need for a daily ration of solitude was his strongest "pre-writing" moment as a child.

Your Behavior Creates Your Gender

Nobody is born one gender or the other, says the philosopher. "We act and walk and speak and talk in ways that consolidate an impression of being a man or being a woman."

Are You a Liberal Snob? Take The Quiz

Charles Mrray designed this quiz to have a salutary effect on bringing to people’s attention the degree to which they live in a bubble that seals them off from an awful lot of their fellow American citizens.

Why You Should Watch Filth

John Waters defends the creation and consumption of obscene films, and recommends some of his personal favorites.

What Are You Worth? Getting Past Status Anxiety.

Writer Alain De Botton says that status anxiety is more pernicious and destructive than most of us can imagine, and recommends getting out of the game altogether.

Sheila Heen on the Psychology of Happiness and Feedback

Sheila Heen, a Partner at Triad Consulting Group and a lecturer on Law at Harvard Law School, explains the psychology behind feedback and criticism. Heen is co-author of "Thanks for the Feedback: The Science and Art of Receiving Feedback Well."

Are You a Psychopath? Take the Test.

Psychologist Kevin Dutton presents the classic psychological test known as "the trolley problem" with a variation. Take the test and measure you response on the psychopathic spectrum.

Here's How to Catch a Liar, If You Really Want To

It’s very complex as to whether or not we really want to catch a liar. We think we do. What if we find out that both of our presidential candidates are lying? Then what do we do? I’m not saying they are; I never comment on anyone in office or running for office. Only after they’re out that they’re fair game. . . . Clinton said, "I didn’t have sex with that woman" and then gave her name. "That woman" is putting her at a distance from himself.

Why I Came Out at Age 81

As a teenager in the '40s, James Randi "would have gotten stoned" for being gay. But when he outed himself to the world in 2010, the reaction was "wonderful."

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  • The Chinese Room thought experiment is designed to show how understanding something cannot be reduced to an "input-process-output" model.
  • Artificial intelligence today is becoming increasingly sophisticated thanks to learning algorithms but still fails to demonstrate true understanding.
  • All humans demonstrate computational habits when we first learn a new skill, until this somehow becomes understanding.

It's your first day at work, and a new colleague, Kendall, catches you over coffee.

"You watch the game last night?" she says. You're desperate to make friends, but you hate football.

"Sure, I can't believe that result," you say, vaguely, and it works. She nods happily and talks at you for a while. Every day after that, you live a lie. You listen to a football podcast on the weekend and then regurgitate whatever it is you hear. You have no idea what you're saying, but it seems to impress Kendall. You somehow manage to come across as an expert, and soon she won't stop talking football with you.

The question is: do you actually know about football, or are you imitating knowledge? And what's the difference? Welcome to philosopher John Searle's "Chinese Room."

The Chinese Room

Credit: http://america.pink/ via Wikipedia and licensed under CC0 1.0

Searle's argument was designed as a critique of what's called a "functionalist" view of mind. This is the philosophy that argues that our mind can be explained fully by what role it plays, or in other words, what it does or what "function" it has.

One form of functionalism sees the human mind as following an "input-process-output" model. We have the input of our senses, the process of our brains, and a behavioral output. Searle thought this was at best an oversimplification, and his Chinese Room thought experiment goes to show how human minds are not simply biological computers. It goes like this:

Imagine a room, and inside is John, who can't speak a word of Chinese. Outside the room, a Chinese person sends a message into the room in Chinese. Luckily, John has an "if-then" book for Chinese characters. For instance, if he gets <你好吗>, the proper reply is <我还好>. All John has to do is follow his instruction book.

The Chinese speaker outside of the room thinks they're talking to someone inside who knows Chinese. But in reality, it's just John with his fancy book.

What is understanding?

Does John understand Chinese? The Chinese Room is, by all accounts, a computational view of the mind, yet it seems that something is missing. Truly understanding something is not an "if-then" automated response. John is missing that sinking in feeling, the absorption, the bit of understanding that's so hard to express. Understanding a language doesn't work like this. Humans are not Google Translate.

And yet, this is how AIs are programmed. A computer system is programmed to provide a certain output based on a finite list of certain inputs. If I double click the mouse, I open a file. If you type a letter, your monitor displays tiny black squiggles. If we press the right buttons in order, we win at Mario Kart. Input — Process — Output.

Can imitation become so fluid or competent that it is understanding.

But AIs don't know what they're doing, and Google Translate doesn't really understand what it's saying, does it? They're just following a programmer's orders. If I say, "Will it rain tomorrow?" Siri can look up the weather. But if I ask, "Will water fall from the clouds tomorrow?" it'll be stumped. A human would not (although they might look at you oddly).

A fun way to test just how little an AI understands us is to ask your maps app to find "restaurants that aren't McDonald's." Unsurprisingly, you won't get what you want.

The Future of AI

To be fair, the field of artificial intelligence is just getting started. Yes, it's easy right now to trick our voice assistant apps, and search engines can be frustratingly unhelpful at times. But that doesn't mean AI will always be like that. It might be that the problem is only one of complexity and sophistication, rather than anything else. It might be that the "if-then" rule book just needs work. Things like "the McDonald's test" or AI's inability to respond to original questions reveal only a limitation in programming. Given that language and the list of possible questions is finite, it's quite possible that AI will be able to (at the very least) perfectly mimic a human response in the not too distant future.

Credit: Oli Scarff via Getty Images

What's more, AIs today have increasingly advanced learning capabilities. Algorithms are no longer simply input-process-output but rather allow systems to search for information and adapt anew to what they receive.

A notorious example of this occurred when a Microsoft chat bot started spouting bigotry and racism after "learning" from what it read on Twitter. (Although, this might just say more about Twitter than AI.) Or, more sinister perhaps, two Facebook chat bots were shut down after it was discovered that they were not only talking to each other but were doing so in an invented language. Did they understand what they were doing? Who's to say that, with enough learning and enough practice, an AI "Chinese Room" might not reach understanding?

Can imitation become understanding?

We've all been a "Chinese Room" at times — be it talking about sports at work, cramming for an exam, using a word we didn't entirely know the meaning of, or calculating math problems. We can all mimic understanding, but it also begs the question: can imitation become so fluid or competent that it is understanding.

The old adage "fake it, 'till you make it" has been proven true over and over. If you repeat an action enough times, it becomes easy and habitual. For instance, when you practice a language, musical instrument, or a math calculation, then after a while, it becomes second nature. Our brain changes with repetition.

    So, it might just be that we all start off as Chinese Rooms when we learn something new, but this still leaves us with a pertinent question: when, how, and at what point does John actually understand Chinese? More importantly, will Siri or Alexa ever understand you?

    Jonny Thomson teaches philosophy in Oxford. He runs a popular Instagram account called Mini Philosophy (@philosophyminis). His first book is Mini Philosophy: A Small Book of Big Ideas.

    • A treasure trove of mobility data from devices like smartphones has allowed the field of "city science" to blossom.
    • I recently was part of team that compared mobility patterns in Brazilian and American cities.
    • We found that, in many cities, low-income and high-income residents rarely travel to the same geographic locations. Such segregation has major implications for urban design.

    Almost 55 percent of the world's seven billion people live in cities. And unless the COVID-19 pandemic puts a serious — and I do mean serious — dent in long-term trends, the urban fraction will climb almost to 70 percent by midcentury. Given that our project of civilization is staring down a climate crisis, the massive population shift to urban areas is something that could really use some "sciencing."

    Is urbanization going to make things worse? Will it make things better? Will it lead to more human thriving or more grinding poverty and inequality? These questions need answers, and a science of cities, if there was such a thing, could provide answers.

    Good news. There already is one!

    The science of cities

    With the rise of Big Data (for better or worse), scientists from a range of disciplines are getting an unprecedented view into the beating heart of cities and their dynamics. Of course, really smart people have been studying cities scientifically for a long time. But Big Data methods have accelerated what's possible to warp speed. As "exhibit A" for the rise of a new era of city science, let me introduce you to the field of "human mobility" and a new study just published by a team I was on.

    Credit: nonnie192 / 405009778 via Adobe Stock

    Human mobility is a field that's been amped up by all those location-enabled devices we carry around and the large-scale datasets of our activities, such as credit card purchases, taxi rides, and mobile phone usage. These days, all of us are leaving digital breadcrumbs of our everyday activities, particularly our movements around towns and cities. Using anonymized versions of these datasets (no names please), scientists can look for patterns in how large collections of people engage in daily travel and how these movements correlate with key social factors like income, health, and education.

    There have been many studies like this in the recent past. For example, researchers looking at mobility patterns in Louisville, Kentucky found that low-income residents tended to travel further on average than affluent ones. Another study found that mobility patterns across different socioeconomic classes exhibit very similar characteristics in Boston and Singapore. And an analysis of mobility in Bogota, Colombia found that the most mobile population was neither the poorest nor the wealthiest citizens but the upper-middle class.

    These were all excellent studies, but it was hard to make general conclusions from them. They seemed to point in different directions. The team I was part of wanted to get a broader, comparative view of human mobility and income. Through a partnership with Google, we were able to compare data from two countries — Brazil and the United States — of relatively equal populations but at different points on the "development spectrum." By comparing mobility patterns both within and between the two countries, we hoped to gain a better understanding of how people at different income levels moved around each day.

      Mobility in Brazil vs. United States

      socioeconomic mobility map US Brazil cities Socioeconomic mobility "heatmaps" for selected cities in the U.S. and Brazil. The colors represent destination based on income level. Red depicts destinations traveled by low-income residents, while blue depicts destinations traveled by high-income residents. Overlapping areas are colored purple.Credit: Hugo Barbosa et al., Scientific Reports, 2021.

      The results were remarkable. In a figure from our paper (shown above), it's clear that we found two distinct kinds of relationship between income and mobility in cities.

      The first was a relatively sharp distinction between where people in lower and higher income brackets traveled each day. For example, in my hometown of Rochester, New York or Detroit, the places visited by the two income groups (e.g., job sites, shopping centers, doctors' offices) were relatively partitioned. In other words, people from low-income and high-income neighborhoods were not mixing very much, meaning they weren't spending time in the same geographical locations. In addition, lower income groups traveled to the city center more often, while upper income groups traveled around the outer suburbs.

      The second kind of relationship was exemplified by cities like Boston and Atlanta, which didn't show this kind of partitioning. There was a much higher degree of mixing in terms of travel each day, indicating that income was less of a factor for determining where people lived or traveled.

      In Brazil, however, all the cities showed the kind of income-based segregation seen in U.S. cities like Rochester and Detroit. There was a clear separation of regions visited with practically no overlap. And unlike the U.S., visits by the wealthy were strongly concentrated in the city centers, while the poor largely traversed the periphery.

      Data-driven urban design

      Our results have straightforward implications for city design. As we wrote in the paper, "To the extent that it is undesirable to have cities with residents whose ability to navigate and access resources is dependent on their socioeconomic status, public policy measures to mitigate this phenomenon are the need of the hour." That means we need better housing and public transportation policies.

      But while our study shows there are clear links between income disparity and mobility patterns, it also shows something else important. As an astrophysicist who spent decades applying quantitative methods to stars and planets, I am amazed at how deep we can now dive into understanding cities using similar methods. We have truly entered a new era in the study of cities and all human systems. Hopefully, we'll use this new power for good.

      • LSD flashbacks have been studied for decades, though scientists still aren't quite sure why some people experience them.
      • A subset of people who take psychedelics and then experience flashbacks develop hallucinogen persisting perception disorder (HPPD), a rare condition in which people experience regular or near-constant psychedelic symptoms.
      • There's currently no cure for the disorder, though some studies suggest medications may alleviate symptoms.

      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.

      lsd flashbacks Credit Newwup 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 LSD 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 LSD 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 LSD 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 LSD 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, LSD 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.

      www.youtube.com

      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 not 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 flashbacks Credit Yurok 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."

      lsd flashbacks Lopyriev via Adobe Stock

      Hope for HPPD

      Since experiencing his first acid 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."

      • Neurotheology is a field that unites brain science and psychology with religious belief and practices.
      • There are several indirect and direct mechanisms that link spirituality with improved mental health.
      • Compassion and love are positive emotions that will make your brain healthier.

      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.

        In Aldous Huxley's 1932 novel “Brave New World," people aren't born from a mother's womb. Instead, embryos are grown in artificial wombs until they are brought into the world, a process called ectogenesis.

        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.

        A drawing of a half–eagle, half–horse griffin.

        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.The Conversation

        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.