Category Archives: Behavior

Teenagers are crazy because they’re just like lizards

Remember that time you went to the zoo, and there were these huge reptiles, like maybe Komodo Dragons, and they just sat around doing nothing? Except every so often one of them would make some vaguely unpleasant noise, or snap viciously at one of the others? And finally it dawned on you that it was just like watching teenagers, and you could have saved yourself the cost of a ticket by hanging out at the mall food court?

Well, as it turns out, you were on to something. Clinical Psychologist Richard Friedman wrote an interesting piece in Sunday’s New York Times in which he argues that many of the behaviors we associate with adolescence — like risk taking, fear, and anxiety — may be a consequence of asynchronous development of different brain structures:

Different regions and circuits of the brain mature at very different rates. It turns out that the brain circuit for processing fear — the amygdala — is precocious and develops way ahead of the prefrontal cortex, the seat of reasoning and executive control. This means that adolescents have a brain that is wired with an enhanced capacity for fear and anxiety, but is relatively underdeveloped when it comes to calm reasoning.

The amygdala is one of the evolutionarily ancient parts of the brain that is involved in things like the “fight or flight” response. If you enjoy using outdated terms and/or trolling brain researchers (and I do!), you would say that this is a component of the “reptilian” brain. The prefrontal cortex is more like the “thinkin’ and plannin'” region, and part of the “mammalian” brain, in that these structures became larger in the evolutionary lineage leading to mammals (and bigger again in primates, and even more biggerer in humans).

If you’re a Daniel Kahneman fan, the reptilian bit is like the fast-thinking System 1, and the mammalian bit is like the slow-thinking System 2.

These two parts are in a sort of balance in children, but, when you enter adolescence, the System 1 stuff matures more quickly, and it dominates the more reflective System 2. Eventually, System 2 catches up, so that the balance is regained in adults.

We’ve recently learned that adolescents show heightened fear responses and have difficulty learning how not to be afraid. In one study using brain M.R.I., researchers at Weill Cornell Medical College and Stanford University found that when adolescents were shown fearful faces, they had exaggerated responses in the amygdala compared with children and adults.

These developmental patterns may help to explain not only certain stereotypical adolescent behaviors, but also perhaps systematic differences in how adolescents and adults respond to certain medications.

Alright, so what are we going to do with this information?

Parents have to realize that adolescent anxiety is to be expected, and to comfort their teenagers — and themselves — by reminding them that they will grow up and out of it soon enough.

Wait, that’s not a magic bullet solution that will allow me to overcome the challenges of raising a child with little or no effort on my part! Between this and the World Cup, it’s like this isn’t even America anymore!

Yes, ALL Men’s Rights Groups are Responsible for Elliot Rodger’s Murders

On Friday, May 23, the nation was stunned by 22-year-old Elliot Rodger, who went on a shooting rampage in Isla Vista, California, where he murdered six people, sent seven others to the hospital, and eventually killed himself. Details about Rodgers emerged quickly, most notably a trail of extreme misogyny in the form of a 140-page manifesto, online videos, and participation in discussions on a site for failed pick-up artists. In his last video message, he said

You forced me to suffer all my life, now I will make you all suffer . . . All you girls who rejected me, looked down upon me, you know, treated me like scum while you gave yourselves to other men. And all of you men for living a better life than me, all of you sexually active men. I hate you. I hate all of you. I can’t wait to give you exactly what you deserve, annihilation.

Within a couple of days, though, the race was on to control the narrative, to define what, exactly, had caused this tragedy. Some people (e.g., at the New Statesman, the American Prospect), pointed to a misogynistic ideology, which is pervasive through much of our culture, and can be found in its most distilled form in the Pick-Up Artist (PUA) and Men’s Rights Activist (MRA) communities.

Other, stupider people tried to point the finger elsewhere. In the Washington Post, film critic Ann Hornaday argued that it was because the “schlubby arrested adolecsent” in Judd Apatow films always gets to have sex. Fox News – presumably after having tried and failed to find some way in which Rodger was actually Black, or Muslim, or a secret-pro-gun-control-false-flag-sacrificial-lamb – ran a segment in which they brought in a psychotherapist / psychologist to speculate that the shootings were the result of his “fighting against his homosexual impulses”.

Obviously, guns were involved in the crime, and the shooting is already being used to argue for new gun control laws, but it appears that the first three victims were stabbed to death. Likewise, mental health was clearly an issue, as it almost always is in these cases. However, to the extent that blame for this crime can be ascribed to “gun culture”, or to the systematic deficiencies in our mental healthcare “system”, both of these causes pale in comparison to the normalization of an extreme, violent misogynistic ideology.

So how, exactly, are the MRA and PUA groups to blame here?  No one is saying that they are directly responsible for these murders. However, in the absence of these groups, and the broader culture of mainstream misogyny, I think it is unlikely that Elliot Rodger would have wound up where he did.

The key concept here is psychological priming. When we evaluate things, whether actions, or people. or values, we evaluate them in comparison to something else. Marketers know this, and they exploit it regularly: sales are attractive because they make us feel like we’re getting a bargain. The fact is, I have no absolute sense of how much a box of mac and cheese should cost. If I walk in to the grocery store and see that it costs $1.59 for a box, I’ll think, “Okay, I guess that’s how much it costs.” But, if I see that it normally costs $1.99, but is on sale for $1.59, I’ll feel like I’m getting a great deal.

Similarly, fancy restaurants often have one or two high-priced items on the menu, and wine stores will stock a handful of bottles of extremely expensive wine. Even if no one ever orders or purchases these high-end goods, it is worth their while to stock them, because their real value is in making the rest of the prices look more reasonable. If there’s a thousand-dollar bottle of wine on display, you’re more likely to spring for the hundred-dollar bottle.

There’s not much question that Elliot Rodger was mentally ill. Maybe it was inevitable that he was going to lash out against women in some way, that he was going to do something horrible that went three steps over the line. MRAs don’t bear any responsibility for that.

What the MRAs and PUAs are responsible for is where the line was. And they’re responsible for working to make it seem normal – even admirable – to stand as close to the line as you can get.

Like most poisonous ideologies, misogyny tends to get whitewashed with Orwellian double-speak and dog whistles. In public discourse, at least, MRAs are not “against women”, they are against “women getting special rights”, just as homophobic bigots are against “special rights for gays”.

More broadly, very few men would claim to have a problem with women, but a lot of men have a problem with women who are “stuck up bitches”, or who are “psycho”, just as most racist troglodytes “don’t have a problem” with black people in general, just the “lazy” or “criminal” or “entitled” ones.

Whether we’re talking about racism or homophobia or misogyny, there is a societal sense of what sorts of statements and actions are and are not appropriate – of where the line is. The finely carved rhetoric of most MRAs is an attempt to make sure that they stay on the right side of that line. In a way, that’s a good thing. The problem is that when you normalize behavior that is just on this side of the line, you make it that much easier for someone who is angry or mentally ill to cross over that line. Because that is how our brains work.

No matter what the societal norms are, there will always be people who are outliers. That means that if you work to create societal norms that are just this side of physical violence towards women, you all but guarantee that there women will be targeted with physical violence.

Imagine if we lived in a society where misogyny was not endemic. Maybe in that society, Elliot Rodger still winds up as a mentally ill kid with a lot of frustration and anger directed at women. Maybe he still steps way over the line of acceptable behavior. But maybe that means that when he goes to a party, hits on a girl, and gets turned down, he throws his beer in her face and calls her a bitch.

Imagine if that was what three steps over the line looked like, and calling a woman a bitch for not going out with you was national news, the sort of thing that would result in someone like Rodger receiving the psychological help he needed.

Is that scenario even possible? Well, just how far the line of societal norms could be moved depends on the answers to a whole lot of nature/nurture questions. But there is no doubt that we could achieve something closer to that scenario than what we have at the moment.

But the other problem is that we have gangs of the Men’s Rights Activists and Pick-Up Artists tripping over each other to position themselves just on this side of what is acceptable. It’s like that scene in World War Z, where the zombies pile on top of each other until some of them can make it over the wall. Elliot Rodger is the one who made it over the wall, but all the MRAs and PUAs who have been normalizing misogyny helped him over, and they absolutely bear responsibility for the murders he committed when he landed on the other side.

The selfish herd

So, one of the most interesting questions in evolutionary biology is the origin of collective behaviors. This can be the complex division of labor that we see in social insects and human societies, flocking behavior in migratory birds, or microbial formation of biofilms. It can be predators engaging in collective hunting, or prey engaging in collective being hunted. It’s this last one that we’re going to be talking about today.

As with many questions in evolutionary biology, there are a couple of dimensions that people are interested in untangling: proximal and ultimate causation. Proximal explanations focus on the “how” part of the solution, as in, “what are the molecular, genetic, etc. mechanisms and environmental cues that result in this behavior?” Ultimate explanations focus on “why,” in the evolutionary sense of “what were the selective pressures that led to the evolution of this behavior?”

Herding or flocking behavior is a classic case. For example, why do sheep hang out in a big group, in contrast to say, leopards, which tend to be pretty solitary? There are a number of possible (and not mutually exclusive) ultimate explanations, but the most talked about one is probably defense against predators.

Best URL for sharing: http://www.darwineatscake.com/?id=135
Permanent image URL for hotlinking or embedding: http://www.darwineatscake.com/img/comic/135.png

Back in the mid-twentieth century, it was common for biologists to talk in fairly loose terms about collective behaviors having evolved as a result of their benefits to the group. Then, in 1966, G. C. Williams published Adaptation and Natural Selection, which dropped a lot of truth into the community. In particular, it emphasized the gene-centered view of natural selection that hit the public consciousness with Richard Dawkins’s 1976 book, The Selfish Gene, and which has remained the dominant paradigm in evolutionary biology ever since.

Williams demonstrated that group selection, while possible, will generally be a much weaker force than selection acting on the individual. Therefore, it is good practice to look for evolutionary explanations at this lower level. Given plausible adaptive stories at the individual and group levels, one should favor the individual-level story. While the two stories might not be mutually exclusive, individual-level selective pressures are more likely to have played an important role in  the evolution of any particular trait than group-level selective pressures (all else being equal, of course).

In 1971, W. D. Hamilton published a theoretical analysis that brought this individual-level perspective to herding behavior. Hamilton argued that all you need is for animals to be trying to evade predators as individuals. If there are other individuals of their type around, they just need to try to position themselves between other individuals. Here’s how Hamilton draws it:

This frog wants to position itself between the two frogs on the right. That way, when the sea snake comes up, it will eat one of the frogs at the edge, and the one in the middle will be safe.

All you need is for everyone to follow one simple rule: when a predator comes, position yourself between two other individuals. What you get then is a tight cluster of individuals.

You can actually try this at home. You probably need about eight or ten people. So, most of you might not be able to try this at home, but you could maybe try it at school or work. Have each person pick two other people in the group (but don’t tell who your picks are). Then, everyone tries to get between the two people they picked. What you’ll get is something a lot like a cluster of frogs climbing all over each other to get away from a sea snake.

Frogs maneuvering to get between other frogs results in the formation of a clusterf**k of frogs. I know, right? I was surprised, too, but my herpetologist friends assure me that “clusterf**k” is the official collective noun for a group of frogs. Don’t even ask about sea snakes. You don’t want to know.

Bonus activity: after you’ve disentangled yourselves from the frogpile, try this one. Each person picks two people again, labeling them “A” and “B” (in your head). Again, no one needs to say whom they picked. Now, each person should position themselves so that their “A” person is between them and their “B” person. If it helps, imagine that “A” is Mitt Romney, that “B” is the American People, and you are Mitt’s tax returns. Your job is to position yourself so that Mitt keeps the American People from seeing you. I won’t spoil how it comes out.

So, Hamilton’s model provides a nice, simple model that can produce the observed behavior. The model is attractive because (1) it requires selection only at the level of the individual, and (2) it requires each individual only to follow a very simple behavioral rule. The collective behavior is an emergent property requiring no coordination at the group level.

Now, there’s a new paper out that is attempting to look at this empirically, in sheep. The study involves strapping adorable GPS backpacks on a bunch of sheep (Figure 1c, below) and then letting a sheepdog chase them around.

You can look at the movies here. It’s only a brief communication, and does not really nail anything down, but the authors interpret their results as broadly consistent with the selfish herd model. In particular, they are able to see that individual sheep seem to be trying to get to the center of the flock.

The cool thing is more the potential for this type of experiment. Yes, Hamilton’s model is attractive and parsimonious, but if we want to understand the rules that actually govern the behavior of sheep when they are faced with a predator (or, in this case, an annoyator), we will need to get good quantitative data on individual behaviors in a variety of contexts.

Plus, look at that little GPS backpack!

I’ll leave you with this.

Best URL for sharing: http://www.darwineatscake.com/?id=136
Permanent image URL for hotlinking or embedding: http://www.darwineatscake.com/img/comic/136.jpg

King AJ, Wilson AM, Wilshin SD, Lowe J, Haddadi H, Hailes S, & Morton AJ (2012). Selfish-herd behaviour of sheep under threat. Current biology : CB, 22 (14) PMID: 22835787

Hamilton, W. D. (1971). Geometry for the Selfish Herd Journal of Theoretical Biology, 31, 295-311 DOI: 10.1016/0022-5193(71)90189-5

Toxoplasmosis Extravaganza: Ride Complete!

So, this week at Darwin Eats Cake, we celebrated our one-year anniversary with a series of nine strips on the zooparasite Toxoplasma gondii. This parasite, which causes Toxoplasmosis, is the reason why pregnant women are encouraged to avoid cat litter.

Here’s the full series, presented for your one-stop-shopping viewing pleasure. The strips do not, I think, assume any expert biological knowledge, so you don’t need to be a parasitologist to enjoy them. However, a dorky and juvenile sense of humor will help a lot. Alternatively, you can read them on the Darwin Eats Cake website, where they look a little better, I think. The series starts at http://www.darwineatscake.com/?id=101.

At this point, Darwin Eats Cake will return to its regular programming schedule, with twice-a-week updates, usually on Mondays and Thursdays, except for those days that have been recognized as official holidays by the Darwin Eats Cake Council of Freeholders and its chairwoman, the duly elected Queen of Naboo.

So, stop by on Monday for a new strip, or any time to trawl the archive: http://www.darwineatscake.com.





It’s Toxoplasmosis week at Darwin Eats Cake

So, tomorrow (March 13) marks the one-year anniversary of the launch of my webcomic Darwin Eats Cake on its very own website (here). Normally, Darwin Eats Cake updates approximately twice a week (hemicircaseptanally), on approximately Monday and Thursday (circa-Mondarily and circa-Thursdarily, I assume). However, to mark this special anniversary occasion, we are rolling out a daily series of strips on Toxoplasma gondii, the parasite responsible for Toxoplasmosis. This bug was recently in the news thanks to a profile of Jaroslav Flegr published recently in the Atlantic (here).

Here are the first two of this week’s six strips:

Best URL for sharing: http://www.darwineatscake.com/?id=101
Permanent image URL for hotlinking or embedding: http://www.darwineatscake.com/img/comic/101.jpg
Best URL for sharing: http://www.darwineatscake.com/?id=102
Permanent image URL for hotlinking or embedding: http://www.darwineatscake.com/img/comic/102.jpg

And remember: Sharing is Caring!

Now we know what a Nittany Lion is

So, if you’re like me, you’ve always sort of wondered what a Nittany Lion is. For a while, I thought it involved crochet somehow, but I guess maybe that would be a Knittany Lion. For years, it remained shrouded in mystery, at least, if you’re like me, and did not actually care enough to check Wikipedia.

But then this week we learned that for the past ten years, or possibly longer, numerous officials at Penn State have been involved in protecting and enabling a serial child rapist. And then, when Penn State’s football coach was fired for his involvement in protecting and enabling a serial child rapist, the school’s students rioted. I think we now have our answer:

Best URL for sharing: http://www.darwineatscake.com/?id=71
Permanent image URL for hotlinking or embedding: http://www.darwineatscake.com/img/comic/71.jpg

Update: via Justin Stapleton on Google+, from now on the Honey Badger will be known as the Nittany Badger

The Genetical Book Review: The Psychopath Test

So, welcome back to the Genetical Book Review! This episode? The Psychopath Test, by Jon Ronon. Ronson is the author of The Men Who Stare at Goats, which the movie was based on.

Also, his name is what my name would be if I were from Iceland.

The Psychopath Test traces Ronson’s exploration of psychopathy: what a psychopath is, how you identify one, the effect they have on society, and society’s efforts to contain them. The book is written engagingly, and makes for a quick read, even if you’re as slow a reader as I am. Ronson mixes historical and medical information with interviews of both psychopaths and the doctors who have sought to define and/or treat them. Some of the accounts, you can imagine, touch on some fairly gruesome events, but the light manner of the writing should make the material palatable even for those with weaker stomachs for that sort of thing.

One of the most interesting things about the book is the fact that the material is presented chronologically — not in the order that things happened, but in the order that Ronson learned about and understood them (ostensibly, at least). The effect is a really interesting one, which fits well with what seems to be one of the books goals. By the end of the book, Ronson has deconstructed the whole notion of sanity/insanity, as well as the motives of doctors, pharmaceutical companies, police, the entertainment industry, and journalists, including himself.

He achieves the effect by writing in a sort of semi-gonzo, close first person, chronicling his own reactions and beliefs along the journey. First, he learns x, and so he believes X. Then, in the next chapter, he learns y, and starts to doubt his belief in X. And so on throughout the book. The result is a message that is fragmented, but also nuanced and faceted. This mixture of sometimes contradictory conclusions actually seems quite fitting, given the complexity of the phenomenon, and our limited understanding of it.

Even out of that complexity though, there are two big take-home messages that rise above the others.

First is the fact that psychopathy is not really a well-defined, discrete thing. There is a continuum not only of severity, but of type. Two people could both score high on the eponymous psychopath test (constructed by Bob Hare, who features prominently in the book), but actually exhibit quite different suites of behavior.

This, of course, is not news to anyone who has spent time studying psychiatric disorders (or any other sort of complex disease). Labeling is a necessary part of science and of medicine, as it is what allows us to communicate with each other in an efficient way. However, we need to keep reminding ourselves that these labels refer to abstractions, and that the thing we care about is typically a lot more complicated, and a lots less well understood, than a monolithic label implies.

Which is to say, while it might not be news, it is always good to be reminded of it.

Second is the idea that there are a lot of aspects of society that have a vested interest in reducing people to their maddest edges, as Ronson puts it. Reality television and daytime talk shows seek out people who have something going on that is crazy enough to be entertaining, and then edit out all the boring (read “sane”) bits. Journalists do likewise, seeking out the extreme behaviors and personalities that will make for good quotations and compelling stories. Pharmaceutical companies benefit monetarily from the application of clinical labels to any behavior that lies outside the norm.

And so forth.

There are obviously a lot of very ill people out there. But there are also people in the middle, getting overlabeled, becoming nothing more than a big splurge of madness in the minds of the people who benefit from it.

The other thing that struck me was the chapter on the DSM, the big book that defines all mental illnesses. I think I had always assumed that there was some sort of rigorous, evidence-based process by which disorders were included or excluded. It seems that, well, not so much. It seems more like it is a veneer of codification laid on top of a bunch of idiosyncratic opinions, passed through a filter of special interests. Sigh.

Basically, if you work in the field, you may already be familiar with many of the stories, and may already have internalized many of the punchlines. But, for most people, The Psychopath Test provides an entertaining, informative, and often troubling look at medicalization and exploitation of mental health in our society.

Ronson, Jon. The Psychopath Test. New York: Riverhead Books, 2011.

Hare, R. D. (1980). A research scale for the assessment of psychopathy in criminal populations Personality and Individual Differences, 1 (2), 111-120 : 10.1016/0191-8869(80)90028-8

Buy it now!!

What’s that? You say you want to buy this book? And you want to support Lost in Transcription at the same time? Well, for you, sir and/or madam, I present these links.

Buy The Psychopath Test  now through:

Amazon

Barnes and Nobleicon

indiebound

Alibrisicon

Why do we make odd faces when we orgasm? A romance in three parts

So, Guillaume’s Mailbag has continued on its mission to provide an adaptive explanation for every existing trait. The most recent trait Guillaume has been tackling was submitted by John Wilkins, who asked, “Why do we make odd faces when we orgasm?”

In case you missed when I’ve plugged him before, JoHn Wilkins (no recent relation) is a philosopher of science in Australia. His most recent book is Species: A History of the Idea, and he runs an excellent blog called Evolving Thoughts. He recently concluded an excellent series of posts on “Atheism, agnosticism and theism” in which he discusses, among other things, what it means to have a belief. You can find the start of that series here.

But back to the face of orgasm. Guillaume took three full strips to answer this one, so I’ve waited until he was done to post them here. I think I’ve finally figured out how to make these full-page versions more readable on the blog, but it involved lowering the resolution of the JPEG, so, for higher-res versions of these three comics, head on over to Darwin Eats Cake. The first of the series of three can be found here.

Best URL for sharing: http://www.darwineatscake.com/?id=44
Permanent image URL for hotlinking or embedding: http://www.darwineatscake.com/img/comic/44.jpg
Best URL for sharing: http://www.darwineatscake.com/?id=45
Permanent image URL for hotlinking or embedding: http://www.darwineatscake.com/img/comic/45.jpg
Best URL for sharing: http://www.darwineatscake.com/?id=46
Permanent image URL for hotlinking or embedding: http://www.darwineatscake.com/img/comic/46.jpg
For those who are interested, a couple of vole and oxytocin citations are provided below to get you started. The vole literature is actually quite extensive and all interesting. I’ve included a relatively recent paper, which will contain citations to a lot of the other work. No peer-reviewed publications are yet available on the eating and mating habits of Ursus philorgasmii.

Ross HE, Cole CD, Smith Y, Neumann ID, Landgraf R, Murphy AZ, & Young LJ (2009). Characterization of the oxytocin system regulating affiliative behavior in female prairie voles. Neuroscience, 162 (4), 892-903 PMID: 19482070

Carmichael MS, Warburton VL, Dixen J, & Davidson JM (1994). Relationships among cardiovascular, muscular, and oxytocin responses during human sexual activity. Archives of sexual behavior, 23 (1), 59-79 PMID: 8135652

Although at least one study suggests that, in men, prolactin is actually more strongly correlated with orgasm than oxytocin is:

Krüger TH, Haake P, Chereath D, Knapp W, Janssen OE, Exton MS, Schedlowski M, & Hartmann U (2003). Specificity of the neuroendocrine response to orgasm during sexual arousal in men. The Journal of endocrinology, 177 (1), 57-64 PMID: 12697037

I can haz rapshur? Endgame effects.

So, you’ve probably heard that the world is ending this Saturday (or, as Tom Scocca explains, sometime between Friday evening and Sunday morning, depending on how the rapture interacts with the time zones). You may already have signed up on Facebook to attend the pre-rapture orgy and/or the post-rapture looting.

Earlier, I posted my discovery that you can be taken up by the rapture even if you’re actively engaging in gay sex when it happens, which is pretty awesome.

But now I want to talk about the timing issue.

Back in January I wrote a post making fun of Harold Camping’s claim that he knew when the rapture was coming. The biblical counter-argument comes from Matthew 24:36, which, in the standard Lolcat edition, reads:

but bout dat dai or hour no wan knows, not even teh angels in heaven, nor teh son, [e] but only teh fathr.

(The non-biblical counter-argument, of course, is, “Wait, what? That’s just stupid.”)

The punchline in my previous post was a variation of the standard one that people like myself like to drop in these situations. In this case, it was, “Look! An evolutionary biologist who was raised in a Unitarian church with an atheist minister knows more about the bible than Harold Camping! Hahahaha!”

This is the bible translation favored by Lost in Transcription.

In fact, this is just one of several places in the bible that emphasize the unpredictability of the rapture (and/or the second coming, which is maybe a different thing — who knew?).

So, what’s that about, then? What it reminds me of is the phenomenon of endgame effects in economic games. If you’re not familiar with endgame effects, well, actually you are, because it is one of those regularities that shows up in life just as much as it does in experimental economics.

I’ll describe this in terms of a public goods game, but the phenomenon occurs in a variety of contexts. In your standard public goods game, players are given some money. Each player chooses how much of their money to contribute to a common pot. The money in the pot is then multiplied by some amount (e.g. 3X), and then divided equally among the players, without regard to whether or not they contributed.

Nice picture illustrating the basic structure of a public goods game. I poached this one from Ben Allen’s blog, which would make him a cooperator, since he made this slide. I would be a defector, since I am freeloading off of his work.

The group as a whole benefits most if everyone puts their whole endowment into the pot. But, each individual gets their best payoff if everyone else donates to the pot, but they don’t. If you run this experiment over and over, you find that people typically start off making a decent contribution (typically ~ 50%), but the contributions decline over time, until eventually pretty much everyone is putting in nothing.

A standard modification, then, is to incorporate a punishment phase after each round of the game. For example, people might be given the option to pay some money in order to have money taken away from one of the people who did not donate to the pot.

The first interesting finding that gets reproduced again and again is that people are willing to pay to punish defectors. The second standard finding is that incorporating a punishment phase stabilizes cooperation. So, given the threat of punishment, people will continue to donate to the pot at a high level.

I was going to write something like, “Punishment in most behavioral economics experiments is monetary rather than physical,” but all I can think is, “This is so wrong on so many levels.” Why do you do this to me, Google? 

Okay, so here’s where the endgame effect comes in. These experiments are typically set up to run a certain number of rounds. Whether the experiment lasts for ten rounds or twenty or a hundred, people will start defecting (contributing less) in the final few rounds. Presumably this is because they know that there will be less opportunity for them to get punished, so they maximize their short term gains.

Now, let’s say you’re starting a religion, and you want to influence people’s behaviors. The first thing you do is you set up a system of rewards and punishments (e.g., heaven and hell). Next, let’s say that you want to be able to convert people. Well, one thing you might do is set up a reset button, say, in the form of forgiveness. This allows you to go up to someone who has not been following your rules, explain to them about the system of rewards and punishments, and tell them that they have the chance not to be punished for their past behavior if they ask for forgiveness and act right moving forward.

This structure sets up a well known issue facing Christianity. In principle, one could completely disregard all of the rules, and then repent at the last minute. If your goal is to get people to act right all the time, one thing you can do is introduce uncertainty about when the reward or punishment is going to be doled out. In fact, this seems to be the explicit goal in many of the relevant passages.

This saying, attributed to George Carlin (or occasionally Rowan Atkinson) can be found on t-shirts, mugs, mouse pads, and bumper stickers. It is sometimes used by actual religious folks, who are either missing or reappropriating the irony.

Matthew 24:43-44 compares the second coming to having a thief break into your house:

but understand dis: if teh ownr ov teh houz had known at wut tiem ov nite teh thief wuz comin, he wud has kept watch an wud not has let his houz be brokd into. so u also must be ready, cuz teh son ov man will come at an hour when u do not expect him.

And the parable of the Ten Virgins (Matthew 25:1-13) is about always being prepared:

“At that tyme the couch of the cieling will be like 10 gurlz who can has some flashlites and go meetz teh man at teh door. 5 wur stoopid and 5 wur not stoopid. Teh stoopid gurlz gotz flashlites, but no baterys. Teh not stoopid onez brot baterys. Teh man wuz gonna be rly late, n tey al took a nap.

“In teh night some dood yelld: ‘It’s teh man! Go meets him!’

“Then al teh gurlz wok up n turnd on teh flashlites. Teh stoopid gurlz said to teh not stoopid gurlz: ‘I can has ur baterys? Mine r dead.’

“‘No’ teh not stoopid gurlz said ‘These r mah baterys! Go buys some.’

“But wile tey wur gone buyin teh baterys, teh man arived. Teh not stoopid gurlz went in wit teh man to his crib to parteh n tey close teh door.

“Latr teh stoopid gurlz came. ‘Dood!’ tey said ‘We r outsid r door, waitin for u to let us in!’

“But teh man said ‘Who r u? Go away, this is mah parteh!’

“So keep redy for teh couch of the cieling, cus u don’t kno wen Jebus is comin bak.

So, the whole thing seems structured to deal with this aspect of human nature that has been shown by lots of different economics experiments, but is well known to you from everyday life, as it was well known to the people writing the new testament two thousand years ago: people will cheat if they think they can get away with it.

Bad behavior is something that you can get away with right up until the point where you can’t.

Selten, R., & Stoecker, R. (1986). End behavior in sequences of finite Prisoner’s Dilemma supergames A learning theory approach Journal of Economic Behavior & Organization, 7 (1), 47-70 DOI: 10.1016/0167-2681(86)90021-1

Study sheds light on coming robot apocalypse

So, in many of the standard narratives, the robot apocalypse is triggered when the machines figure out that humans are fundamentally flawed, or because their self awareness produces an instinct for self defense.

Well, a new paper just out in Biological Psychiatry describes an experiment in which researchers successfully teach a computer to reproduce aspects of schizophrenia. This raises the possibility of an alternative scenario: the machines just go crazy and start killing people, Loughner-style.

After suffering from paranoid delusions, Skynet sends Vernon Presley back in time to kill his own grandfather, or something.

Actually, the paper reports a study in which a computational (neural network) model is used to examine eight different putative mechanistic causes of a particular set of symptoms often seen in schizophrenia: narrative breakdown, including the confusion of autobiographical and non-autobiographical stories. This models one putative source of self-referential delusions.

The basic setup is that the researchers use an established system of neural networks called DISCERN. The system is trained on a set of 28 stories. Once the system is trained, you can feed it the first part of any one of the stories, and it will regurgitate the rest of the appropriate story.

Half of the stories are autobiographical, everyday stuff like going to the store. The other half are crime stories, featuring police, mafia, etc.

The experiment is to mess with the DISCERN network in one of eight different ways. Each of the eight types of perturbation is meant to instantiate a neural mechanism that has been proposed to cause delusions in schizophrenia. Then, the researchers feed the computer the first line of a story and look at the magnitude and nature of the errors in the output.

Models were evaluated by their ability to reproduce errors seen in an experimental group of subjects diagnosed with schizophrenia. Basically, they are interested in finding perturbations that mix up different stories, so that the “I” of the autobiographical stories becomes associated with the gangsters and police in the non-autobiographical crime stories.

Two of the eight perturbations performed significantly better than the others:

  1. Working memory disconnection: Connections within the neural network that fell below a certain threshold strength were discarded.
  2. Hyperlearning: During the backpropagation part of the neural network training, the learning algorithm overreacts to prediction errors. After DISCERN was trained, hyper-trained for an additional 500 cycles.
These two were then further extended, with the addition of a parameter to each, at which point the modified hyperlearning model outperformed the disconnection model. 
So, what to make of it?  It seems like an interesting piece of work. It is hard to know how much light this sheds on schizophrenia, since the brain is a heck of a lot bigger and more complicated than this model. And, well, sometimes things scale up in the straightforward way, and sometimes they don’t. 
What one hopes will be the outcome of this sort of work is that is will prompt additional research. While we can’t guarantee that results extrapolated from computational systems such as this one will have any predictive value for the brain. But, it should be possible at least to construct predictions. A collaboration involving neuroscientists of various stripes could then potentially come up with some clever experiments, which would be interesting, if for no other reason than that they had a direct connection back to this sort of computational model.
Spot-on commentary. Via, as usual, xkcd.
The other thing we can take away is this. We now know how to train up a schizophrenic neural network. Combine it with this punching robot:
Asimov’s-law-violating robot. Via Geekologie.

Teach it to snort coke, and we’ve got all the makings of a Charlie Sheen bot.

Hoffman RE, Grasemann U, Gueorguieva R, Quinlan D, Lane D, & Miikkulainen R (2011). Using computational patients to evaluate illness mechanisms in schizophrenia. Biological psychiatry, 69 (10), 997-1005 PMID: 21397213

For more on this article, check out 80beats, over at Discover Blogs.