Astral Codex Ten Podcast

Jeremiah
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May 17, 2019 • 6min

A Critical Period for Lactation Fetishes

Enquist et al on lactation fetishes is one of my favorite papers. They wonder – as we've all wondered at one point or another – how people develop fetishes. One plausible hypothesis is "sexual imprinting". During childhood, you have a critical period (maybe ages 1 to 5) where you figure out what sex is. If you see some weird stuff during that time, you could end up with a fetish. For example, a child who sees latex used in a sexualized way (for example, they catch a glimpse of a sexy movie where someone is wearing latex) might grow up with a latex fetish. Enquist et al realize lactation fetishes offer a natural test of this hypothesis. Children with younger siblings will see a lot of breastfeeding going on during their critical window; children without younger siblings will see less. Since it's easy to ask people how many siblings they have, you can see if younger siblings correlate with lactation fetishes. They survey some online lactation fetishist communities and ask everyone how many older and younger siblings they have. Although by chance we would expect an equal number of both, in fact the fetishists have many more younger than older siblings:
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May 16, 2019 • 12min

Age Gaps and Birth Order Effects

Psychologists are split on the existence of "birth order effects", where oldest siblings will have different personality traits and outcomes than middle or youngest siblings. Although some studies detect effects, they tend to be weak and inconsistent. Last year, I posted Birth Order Effects Exist And Are Very Strong, finding a robust 70-30 imbalance in favor of older siblings among SSC readers. I speculated that taking a pre-selected population and counting the firstborn-to-laterborn ratio was better at revealing these effects than taking an unselected population and trying to measure their personality traits. Since then, other independent researchers have confirmed similar effects in historical mathematicians and Nobel-winning physicists. Although birth order effects do not seem to consistently affect IQ, some studies suggest that they do affect something like "intellectual curiosity", which would explain firstborns' over-representation in intellectual communities. Why would firstborns be more intellectually curious? If we knew that, could we do something different to make laterborns more intellectually curious? A growing body of research highlights the importance of genetics on children's personalities and outcomes, and casts doubt on the ability of parents and teachers to significantly affect their trajectories. But here's a non-genetic factor that's a really big deal on one of the personality traits closest to our hearts. How does it work? People looking into birth order effects have come up with a couple of possible explanations: 1. Intra-family competition. The oldest child choose some interest or life path. Then younger children don't want to live in their older sibling's shadow all the time, so they do something else. 2. Decreased parental investment. Parents can devote 100% of their child-rearing time to the oldest child, but only 50% or less to subsequent children.
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May 12, 2019 • 9min

Is There a Case for Skepticism of Psychedelic Therapy?

There's been an explosion of interest in the use of psychedelics in psychiatry. Like everyone else, I hope this works out. But recent discussion has been so overwhelmingly positive that it's worth reviewing whether there's a case for skepticism. I think it would look something like this: 1. Psychedelics have mostly been investigated in small studies run by true believers. These are the conditions that produce a field made of unreplicable results, like the effects of 5-HTTLPR. Some of the most exciting psychedelic findings have already failed to replicate; for example, a study two years ago found that psilocybin did not permanently increase the Openness personality trait. This was one of the most exciting studies and had shaped a lot of my thinking around the issue. Now it's gone. 2. Some of the most impressive stories involve psychedelic-assisted psychotherapy, where people who talk with a therapist, while on a substance, obtain true insight and get real closure. But every psychotherapy has amazing success stories floating out there. Back when psychoanalysis was new, the whole world was full of people telling their amazing success stories about how Dr. Freud helped them obtain true insight and get real closure. I think of psychotherapy as a domain where people can get as many amazing success stories as they want whether or not they're really doing anything right, for unclear reasons.
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May 10, 2019 • 24min

5-HTTLPR: A Pointed Review

In 1996, some researchers discovered that depressed people often had an unusual version of the serotonin transporter gene 5-HTTLPR. The study became a psychiatric sensation, getting thousands of citations and sparking dozens of replication attempts (page 3 here lists 46). Soon scientists moved beyond replicating the finding to trying to elucidate the mechanism. Seven studies (see herefor list) found that 5-HTTLPR affected activation of the amygdala, a part of the brain involved in processing negative stimuli. In one especially interesting study, it was found to bias how the amygdala processed ambiguous facial expression; in another, it modulated how the emotional systems of the amygdala connected to the attentional systems of the anterior cingulate cortex. In addition, 5-HTTLPR was found to directly affect the reactivity of the HPA axis, the stress processing circuit leading from the adrenal glands to the brain. As interest increased, studies began pointing to 5-HTTLPR in other psychiatric conditions as well. One study found a role in seasonal affective disorder, another in insomnia. A meta-analysis of twelve studies found a role (p = 0.001) in PTSD. A meta-analysis of twenty-three studies found a role (p = 0.000016) in anxiety-related personality traits. Even psychosis and Alzheimer's disease, not traditionally considered serotonergic conditions, were affected. But my favorite study along these lines has to be 5-HTTLPR Polymorphism Is Associated With Nostalgia-Proneness. Some people in bad life situations become depressed, and others seem unaffected; researchers began to suspect that genes like 5-HTTLPR might be involved not just in causing depression directly, but in modulating how we respond to life events. A meta-analysis looked at 54 studies of the interaction and found "strong evidence that 5-HTTLPR moderates the relationship between stress and depression, with the s allele associated with an increased risk of developing depression under stress (P = .00002)". This relationship was then independently re-confirmed for every conceivable population and form of stress. Depressed children undergoing childhood adversity. Depressed children with depressed mothers. Depressed youth. Depressed adolescent girls undergoing peer victimization. They all developed different amounts of depression based on their 5-HTTLPR genotype. The mainstream media caught on and dubbed 5-HTTLPR and a few similar variants "orchid genes", because orchids are sensitive to stress but will bloom beautifully under the right conditions. Stories about "orchid genes" made it into The Atlantic, Wired, and The New York Times. In 1996, some researchers discovered that depressed people often had an unusual version of the serotonin transporter gene 5-HTTLPR. The study became a psychiatric sensation, getting thousands of citations and sparking dozens of replication attempts (page 3 here lists 46). Soon scientists moved beyond replicating the finding to trying to elucidate the mechanism. Seven studies (see herefor list) found that 5-HTTLPR affected activation of the amygdala, a part of the brain involved in processing negative stimuli. In one especially interesting study, it was found to bias how the amygdala processed ambiguous facial expression; in another, it modulated how the emotional systems of the amygdala connected to the attentional systems of the anterior cingulate cortex. In addition, 5-HTTLPR was found to directly affect the reactivity of the HPA axis, the stress processing circuit leading from the adrenal glands to the brain. As interest increased, studies began pointing to 5-HTTLPR in other psychiatric conditions as well. One study found a role in seasonal affective disorder, another in insomnia. A meta-analysis of twelve studies found a role (p = 0.001) in PTSD. A meta-analysis of twenty-three studies found a role (p = 0.000016) in anxiety-related personality traits. Even psychosis and Alzheimer's disease, not traditionally considered serotonergic conditions, were affected. But my favorite study along these lines has to be 5-HTTLPR Polymorphism Is Associated With Nostalgia-Proneness. Some people in bad life situations become depressed, and others seem unaffected; researchers began to suspect that genes like 5-HTTLPR might be involved not just in causing depression directly, but in modulating how we respond to life events. A meta-analysis looked at 54 studies of the interaction and found "strong evidence that 5-HTTLPR moderates the relationship between stress and depression, with the s allele associated with an increased risk of developing depression under stress (P = .00002)". This relationship was then independently re-confirmed for every conceivable population and form of stress. Depressed children undergoing childhood adversity. Depressed children with depressed mothers. Depressed youth. Depressed adolescent girls undergoing peer victimization. They all developed different amounts of depression based on their 5-HTTLPR genotype. The mainstream media caught on and dubbed 5-HTTLPR and a few similar variants "orchid genes", because orchids are sensitive to stress but will bloom beautifully under the right conditions. Stories about "orchid genes" made it into The Atlantic, Wired, and The New York Times.
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May 4, 2019 • 3min

Little Known Types of Eclipse

A lunar eclipse occurs when the Earth gets between the Moon and the Sun. A solar eclipse occurs when the Moon gets between the Earth and the Sun. A terrestrial eclipse occurs when the Earth gets between you and the Sun. Happens once per 24 hours. An atmospheric eclipse occurs when an asteroid gets between you and the sky. Generally fatal. A reverse solar eclipse occurs when the Sun gets between the Moon and the Earth. Extremely fatal. A motivational eclipse occurs when the Moon gets between you and your goals. You can't let it stop you! Destroy it! Destroy the Moon! A marital eclipse occurs when the Moon gets between you and your spouse. You're going to need to practice good communication about the new celestial body in your life if you want your relationship to survive. A capillary eclipse occurs when your hair gets between your eyes and the Sun. Get a haircut.
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May 4, 2019 • 7min

Update to Partial Retraction of Animal Value and Neuron Number

A few weeks ago I published results of a small (n = 50) survey showing that people's moral valuation of different kinds of animals scaled pretty nicely with the animals' number of cortical neurons (see here for more on why we might expect that to be true). A commenter, Tibbar, did a larger survey on Mechanical Turk and got very different results, so I retracted the claim. I wasn't sure why we got such different results, but I chalked it down to chance, or perhaps to my having surveyed an animal-rights-conscious crowd who thinks a lot about this kinds of things vs. Tibbar surveying random MTurkers. Now David Moss, from effective altruist organization Rethink Priorities, has looked into this more deeply and resolved some of the discrepancies. The problem is that I did a terrible job explaining my procedure (I linked to the form I used, but the link was broken when Tibbar did his survey). In particular, I included the line: If you believe [animals have moral value] in general, but think some specific animal I ask about doesn't work this way, feel free to leave the question blank or put in "99999", which I will interpret as "basically infinity"
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May 3, 2019 • 20min

Buspirone Shortage in Healthcaristan SSR

(Epistemic status: Unsure on details. Some post-publication edits 5/1 to make this less strident.) I. There is a national shortage of buspirone. Buspirone is a 5HT-1 agonist used to control anxiety. Unlike most psychiatric drugs, it's in a class of its own – there are no other sole 5HT-1 agonists on the market. It's not a very strong medication, but it's safe, it's non-addictive, it's off-patent, and it works well for a subset of patients. Some of them have been on it for years. Now there's a national shortage. My patients can't get it, or have to go hunting from pharmacy to pharmacy until they find one that has it. I've told people find a source to stockpile a supply so they don't run out. It feels like we're living in the Soviet Union. How did this happen? The New York Times writes: The main reason for the buspirone shortage appears to be interrupted production at a Mylan Pharmaceuticals plant in Morgantown, W.Va., which produced about a third of the country's supply of the drug. The Food and Drug Administration had said the facility was dirty and that the company failed to follow quality control procedures.
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Apr 24, 2019 • 28min

1960: The Year the Singularity Was Cancelled

[Epistemic status: Very speculative, especially Parts 3 and 4. Like many good things, this post is based on a conversation with Paul Christiano; most of the good ideas are his, any errors are mine.] I. In the 1950s, an Austrian scientist discovered a series of equations that he claimed could model history. They matched past data with startling accuracy. But when extended into the future, they predicted the world would end on November 13, 2026. This sounds like the plot of a sci-fi book. But it's also the story of Heinz von Foerster, a mid-century physicist, cybernetician, cognitive scientist, and philosopher. His problems started when he became interested in human population dynamics. (the rest of this section is loosely adapted from his Science paper "Doomsday: Friday, 13 November, A.D. 2026") Assume a perfect paradisiacal Garden of Eden with infinite resources. Start with two people – Adam and Eve – and assume the population doubles every generation. In the second generation there are 4 people; in the third, 8. This is that old riddle about the grains of rice on the chessboard again. By the 64th generation (ie after about 1500 years) there will be 18,446,744,073,709,551,616 people – ie about about a billion times the number of people who have ever lived in all the eons of human history. So one of our assumptions must be wrong. Probably it's the one about the perfect paradise with unlimited resources. Okay, new plan. Assume a world with a limited food supply / limited carrying capacity. If you want, imagine it as an island where everyone eats coconuts. But there are only enough coconuts to support 100 people. If the population reproduces beyond 100 people, some of them will starve, until they're back at 100 people. In the second generation, there are 100 people. In the third generation, still 100 people. And so on to infinity. Here the population never grows at all. But that doesn't match real life either.
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Apr 19, 2019 • 35min

Highlights From the Comments on College Admissions

HalTheWise discusses a factor I missed (until I sneakily edited it in, so you may have read the later version that included it): One very powerful contributor that Scott did not mention is that in many cases schools are directly or indically intentivized to have a low admission rate. US news & world report released the first national college ranking in 1983, and donors and board members at various schools have increasingly been using national rankings performance, which directly includes low admissions rates, as a measure of how well a school is doing. These rankings and metrics also heavily incentivize having high yield (a large fraction of students that are admitted end up attending) which for a fixed size applicant pool also encourages accepting as few people as possible. This has led to the death of safety schools, because they would rather reject a high performing student than admit them and have them not attend. These factors might also be a driving force behind the rise of common app, since schools are trying to get as many applicants as possible, even if it hurts the quality of their pool. kaakitwitaasota points out that consulting is an exception to the "where you go to school doesn't matter" principle:A lot of top firms these days won't even look at you if you didn't go to the "right" college. My mother did her MBA at Northeastern, and recently had lunch with an old classmate who ended up at a top consulting firm. My mother's classmate's résumé would end up in the trash unread these days–Northeastern isn't considered good enough. So while it's probably true on the macro level that smart kids will do just fine anywhere they end up, there is a subset of extremely prestigious, extremely well-paid jobs which will not even look at you if you didn't get into the right institution at the age of 18–which, in practice, means that the élite are chosen on the basis of who they were at the age of 14-17. When viewed in those terms, it's completely nuts. I'd heard this before; my impression is that a big part of consulting is having prestigious-looking people tell you what you want to hear. If what they're actually hiring for is prestige rather than competence per se, that could make it a special case
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Apr 19, 2019 • 1h 8min

Increasingly Competitive College Admissions: Much More Than You Wanted to Know

0: Introduction This is from businessstudent.com Acceptance rates at top colleges have declined by about half over the past decade or so, raising concern about intensifying academic competition. The pressure of getting into a good university may even be leading to suicidesat elite high schools. Some people have dismissed the problem, saying that a misplaced focus on Harvard and Yale ignores that most colleges are easier to get into than ever. For example, from The Atlantic, Is College Really Harder To Get Into Than It Used To Be?: If schools that were once considered "safeties" now have admissions rates as low as 20 or 30 percent, it appears tougher to get into college every spring. But "beneath the headlines and urban legends," Jim Hull, senior policy analyst at the National School Board Association's Center for Public Education, says their 2010 report shows that it was no more difficult for most students to get into college in 2004 than it was in 1992. While the Center plans to update the information in the next few years to reflect the past decade of applicants, students with the same SAT and GPA in the 90's basically have an equal probability of getting into a similarly selective college today. Their link to the report doesn't work, so I can't tell if this was ever true. But it doesn't seem true today. From Pew: The first graph shows that admission rates have decreased at 53% of colleges, and increased at only 31%. The second graph shows that the decreases were mostly at very selective schools, and the increases were mostly at less selective schools. We shouldn't exaggerate the problem: three-quarters of US students go to non-selective colleges that accept most applicants, and there are more than enough of these for everyone. But if you are aiming for a competitive school – not just Harvard and Yale, but anywhere in the top few hundred institutions – the competition is getting harder. This matches my impression of "facts on the ground". In 2002, I was a senior at a California high school in a good neighborhood. Most of the kids in my class wanted to go to famous Ivy League universities, and considered University of California colleges their "safety schools". The idea of going to Cal State (California's middle- and lower- tier colleges) felt like some kind of colossal failure. But my mother just retired from teaching at a very similar school, and she says nowadays the same demographic of students would kill to get into a UC school, and many of them can't even get into Cal States. The stories I hear about this usually focus on how more people are going to college today than ever, but there's still only one Harvard, so there's increasing competition for the same number of spots.

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