Language That Is Person-First

An editorial in the Canadian Medical Association Journal by Roger Collier highlights the problem of Person-first language: Laudable cause, horrible prose

Person-first language (or language that is person-first, as it prefers to be known) is the nice idea that rather than calling someone, say, "blind", we should call them "a person who is blind", so as to remind everyone that they're not defined by their blindness but are a person first... clever, eh?

No. For one thing, it's just bad English. As Collier puts it: "There’s a reason Ernest Hemingway didn’t call his novel The Person Who Was Male and Advanced in Years and the Sea."

He goes on to quote linguist Helena Halmari who highlights a number of problems with the approach:

In English, emphasis naturally occurs at the end of sentences... so by pushing mention of a disability or disease deeper into a sentence, adherents to person-first language may actually be adding stress to those words. “What you have at the end of a sentence is the new information that gets the most attention,” says Halmari.

Worse yet...

Tucking the disability behind the noun may contribute to stigma rather than reduce it. After all, most adjectives with positive connotations precede nouns. We do not typically say a “person who is beautiful,” for instance, or a “person who is intelligent.” Sticking a word in the shadow of a noun can create the impression that there is something inherently wrong with it - that it should be hidden.

As a 'person with mental illness', I entirely agree. I am a man, a neuroscientist, a blogger; I'm not ashamed of those things, so I don't feel the need to erect linguistic fences between them and my person. I am also a psychiatric patient, a depressive, mentally ill; I'm not ashamed of that, either, and I resent the implication - however well-intentioned - that I should.

To me that's the really troubling part of this: the should aspect. The only reason you should not call someone something, is because they ask you not to.

Person-first advocates claim to be speaking on behalf of the 'group' who are harmed and offended by the current use of language - but who gave them that right? They don't speak for me, or anyone but themselves. I don't see 'the mentally ill' as a group at all, but even if it is one, they're certainly not our  elected representatives.

So non-person-first language doesn't offend me. In fact, I'm more worried by the idea that people will assume that, because I'm mentally ill, I want them to use person-first language. Now that's offensive.

How To Respond to Criticism

People argue. On the internet, especially. Here's some tips on how best to respond to criticism of your ideas or writing - in my experience (the fact that I've often failed to follow these rules myself is part of that experience.)

Be Nice

Aggressive and insulting responses are a sign of weakness, and readers know it. If you're confident in your position, you can afford to be nice, and it makes your whole case look more convincing. Quite apart from the fact that it's just, well, nice.

Don't call out people for not being nice, though. The Three V's - "vitriolic", "virulent" and "violent" - seem to be especially common complaints. The trouble is that just as remarking on someone's faux pas is, itself, a faux pas, proclaiming that your opponent is using nasty language lowers the tone of your response.

It's natural to feel hurt by insults, but keep your feelings to yourself. Even if the criticism really is appallingly vicious, let it speak for itself: just slip a quote of the worst bits into your response, by way of making a separate point, and don't lower yourself by commenting on it.

Complimenting critics shows strength. It shows that you're confident that, despite the praise you're heaping on them, you're still right. So be generous. It only works if it seems sincere, though, so no outright brown-nosing.

Be Fresh

Don't just defend the ground you've already occupied - take the offensive (without being offensive). Bring new arguments to the table. New facts are always good - if a critic tries to debunk an example you used to prove a point, don't bother to quibble with them: produce three more.

Make your response readable. A reply is a piece of writing like any other, and it should be as concise and as clear as possible. Exhaustive replies are counterproductive; they're unlikely to be read. Just identify the key criticisms, and respond to those.

Stick to the point. Readers want you to engage with the issues. You may feel that you know all about your detractors' beliefs, character, motives and so forth, and that these are interesting. They rarely are.

Be Right

Often forgotten, this one.

If you're not sure whether you're right, find out. Take your time. If you have to say something right now, say you're working on it. Better a late reply than a bad reply.

If you're wrong, admit it. People will forgive an honest mistake, if you hold up your hands and ask them to. A reputation for admitting your mistakes and correcting your views is actually a point in your favor

If you've done something wrong, apologize. And nothing more. Don't try and justify yourself; it never works. Don't try and get people to pity you; it'll ensure no-one does. Just say sorry, and then keep quiet until the whole thing cools down.

Are Porn Stars Happier?

Women who appear in porn are happier than other women, enjoy sex more - and have lots more of it.

So says a new paper with the pulls-no-punches title of Pornography Actresses: An Assessment of the Damaged Goods Hypothesis

Researchers James Griffith and colleagues sampled 177 American adult actresses, and an equal number of other women of the same age, gender and relationship status. The results were pretty clear: the actresses said they started having sex earlier; had far more partners with an average of 75 vs. 5 in their lifetime (and that's not including on camera).

They were a lot more likely to be bisexual (67% vs 7%!), enjoyed sex more, and reported slightly higher levels of sexual satisfaction, happiness and self-esteem.

On the other hand, they were more worried about STDs and took more drugs (50% had tried ecstasy, 40% cocaine and 27% methamphetamine.)

Finally - and the authors emphasize this - they were no more likely than other women to have suffered childhood sexual abuse. They're not 'damaged goods' as that horrible phrase has it.

So. Well. This study is clearly going to become a hot potato, or rather a political football in The Great Porn Debate, so let's take a calm look at it.

In any survey the fundamental question is - are the respondents representative examples? Or were the porn actresses who filled out the questionnaire atypically happy? Were the comparison women unusually miserable?

We really have no way of knowing. The controls were recruited from a university and an airport, which is pretty sensible although it might introduce some bias. The actresses came via adverts placed in an L.A. clinic specifically for the adult movie industry, the now-defunct AIMHF. That seems like a selective sample - but the clinic reportedly catered to most, if not all, stars in LA because all performers had to get monthly HIV tests there.

Ultimately, though, we don't know how representative they were.

Next up, it was all self-report. So the reports might have been wrong. However, that's a feature of all survey studies, especially those about such things as happiness. It's hard to see a way around this. It's also not clear what bias it would introduce into the results. It could be that the porn actresses were motivated to exaggerate their happiness in a bid to defend their industry, which I suspect will be a common criticism - but that assumes they're happy enough with it to want to defend it, so it's somewhat circular.

Finally, and most importantly in my view, L.A. porn stars are not your average pornstars. The American professional adult movie industry is the biggest, most regulated, and most 'mainstream' in the world. Sadly elsewhere the degree of exploitation, coercion, poverty and abuse among people who end up in porn is a lot higher.

Basically, I can't see anything obviously wrong with this study as far as it goes, but all it shows is that American porn actresses are in fairly good shape. Most women in porn, however, are not American.

Griffith JD, Mitchell S, Hart CL, Adams LT, and Gu LL (2012). Pornography Actresses: An Assessment of the Damaged Goods Hypothesis. Journal of sex research PMID: 23167939

John Bargh's "Transient and Ephemeral" Blogs

Leading social psychologist and Yale Professor John Bargh has been at the center of a number of controversies lately.

Most recently, researcher Brent Donnellan covered a case in which he was unable to replicate one of Bargh's experiments, which prompted Bargh to share his original raw data with him, but on the condition that he never discussed it publicly: What’s the First Rule about John Bargh’s Data? You do not talk about John Bargh’s data

But a couple of months back, even more sparks flew over an unrelated non-replication. Some other people didn't reproduce a different Bargh study.

In response to that non-replication, Bargh published two blog posts called "Nothing In Their Heads" and "Angry Birds", criticizing both the study itself and the journal it appeared in, PLoS ONE. It was a combative defence of his work.

However, Bargh seems to have since decided it was a bit too defensive, because the posts have been deleted. They just vanished: to my knowledge Bargh hasn't announced this, nor explained why.

Now interestingly enough, Bargh has just published a short paper in which he offers he thoughts on blogging - it's rather topical...

Debate among psychologists takes place formally in the published record of journal articles and books... this is the permanent record, as opposed to the relatively transient and ephemeral world of blogs.

As I understand (and use) them, blogs are like newspaper columns or spontaneous radio interviews, and meant to be a forum wherein one can provide the interested public with opinions, feelings, and conjectures; blogs are thus a potentially valuable outlet for ideas when used and evaluated appropriately...

[but they are] personal property whereas journal articles are public property
– as illustrated by one’s ability to edit, change, or delete one’s personal blog entries and one’s concomitant inability to do the same with published works (except to make necessary corrections with the consent of the journal editor).

Fair enough. However, the fact is, a public statement is a public statement. You can change your mind, but you can't change the past. In my book, to try to erase your past statements from the record is both deceptive - and counterproductive.

The internet never forgets... well, actually, I can't find copies of the deleted posts (Edit: See the comments, someone has saved them), so maybe it does, however there are dozens of references to them online, many highly critical. At best, what Bargh has achieved is that his critics are now the only sources for information about his work.

Bargh's new paper, by the way, is a response to this piece I blogged about about the question of free will.

Bargh, J. (2012). Social psychology cares about causal conscious thought, not free will per se British Journal of Social Psychology DOI: 10.1111/bjso.12011

The Coming Age of Fetal Genomics

It's 2020. A young woman and her partner have just found out that she's pregnant with her first child. and they're going to be parents.

They're overjoyed, of course. But they're also worried. They've seen the adverts warning parents-to-be about the risk of de novo mutations - genetic mistakes that occur inside sperm or egg cells, and affect the child. These mutations, the ads say, are much more common than previously believed and they can cause all kinds of problems: intellectual disabilities, autism, infertility, mental illness, heart malformations - pretty much anything.

The scariest part? Because these are new mutations, out of the blue, they can affect any family. A clear family history is no protection. They don't discriminate by race or lifestyle. It's just the luck of the draw - except that older parents are at much higher risk, especially older fathers. In the case of our couple, she's 28 and he's 32. Perfectly normal for this day and age - but very old in biological terms. Humans evolved to be grandparents by 32, not parents. "The stakes couldn't be higher. Why leave it to chance?"

So they don't. Instead, they buy a $100 test kit, they each provide a small blood sample and send it off to one of the companies offering fetal genome testing. At the testing lab, they can separate out the mother's DNA from that of the fetus, both of which are present in the mother's blood. By comparing the fetal genome to the mother's and father's, it's easy to spot de novo mutations. If a certain gene doesn't match either the mother or the father's sequence, it's mutated.

A few days later the results are back. There are several mismatches detected. Most are benign - they're not predicted to have any biological effects. But there's one, a deletion of a few thousand bases in a gene involved in brain development. This deletion is predicted to raise the risk of epilepsy and autism from 1% to 10% apiece.

The parents now have a decision to make. The mutation is a one off, it's not inherited. If they conceive again... roll the dice again... and it'll be gone. Do they terminate?

Like the adverts say, "Some people disagree with this, but we say there's only one person who really matters: your baby."

*

This is likely to become possible in the next few years.

A paper just published in Nature reports on the Non-invasive prenatal measurement of the fetal genome. The technique relies on the fact that the blood of a pregnant woman contains DNA: hers, obviously, but also that of the unborn child. This cell-free DNA can be extracted and genotyped.

This has been possible for a few years, but until now, only fairly crude genetic information could be detected. An extra chromosome, such as in Down syndrome, is pretty easy to spot. This technique is already used to diagnose Down's syndrome and a few other disorders prenatally.

But those diseases are just the low-hanging fruit at the tip of the iceberg, if you see what I mean. To gather the kind of detailed genomic information that could diagnose thousands of disorders is harder: the fetal and maternal genomes are mixed up, and the challenge is to tease them apart. But according to the Stanford geneticists behind the Nature paper, and other teams, it's now possible as early as the first trimester.

What makes the new method so revolutionary is that it is, as the title of the paper says, non-invasive. It's already possible to sequence a fetal genome, but it takes a surgical procedure involving inserting a needle into the womb, and a degree of risk. It's not something you can just sit down and do - but blood samples are. So cell-free DNA will make fetal genomics a personal choice, a commercial product.

The resolution's still not 100%, but inevitably, it will become cheaper, faster and more accurate as technology advances. This year we're expected to see the cost of reading a whole human genome falling below $1000. Fetal genomes will be more expensive, but not enormously so. In 5 or 10 years, it's likely to be affordable.

*

What will happen? I think there'll be demand for such services. Most parents won't do it, but enough people will that it will be a major issue. Just look at countries where boys are more valued than girls: a lot of sex-selective abortion happens. Today, it's limited to gender, because it's easier to determine a fetus's sex than its genome. In 5 or 10 years, they'll both be easy.

With demand will come companies to supply these services and, inevitably, advertizing. I doubt these adverts will be on TV, because there will be opposition to the whole idea and boycotts of broadcasters who run them. But we'll be getting spam emails about it. People will worry even over the harmless mutations: a variant won't need to be really associated with a disease, just believed to be, to make people panic.

Socially, it's likely to be divisive. The anti-abortion types will obviously not approve. But it will drive a wedge between those who support abortion but oppose "discriminatory" abortion against the disabled, and those who support the right to terminations 'for any reason, or none'.

Politically, there will be pressure to regulate this, but legally, it'll be tricky. I can't see how you'd prove that any given abortion is motivated by genetic concerns, so unless you ban abortion outright, that won't work. Banning fetal (or all) genomics except under medical supervision might be possible, but people could always go (or send a few drops of blood) abroad to get around that.

I'm not sure where I'll stand on this, but it looks very likely that we'll each have to make a decision in the coming years.

Fan HC, Gu W, Wang J, Blumenfeld YJ, El-Sayed YY, and Quake SR (2012). Non-invasive prenatal measurement of the fetal genome. Nature PMID: 22763444

Homosexuals Are Smart?

Evolutionary psychologist Satoshi Kanazawa has never been far from controversy. When he's not having his blog cancelled for saying black women are unattractive, he's arguing that some nations just aren't smart enough to be monogamous.

Given which, his latest work, saying that gay people are smarter on average, is probably his most politically correct paper in years, strange as that may sound.

In three large population surveys (USA's AddHealth and GSS, UK's NCDS), Kanazawa found a small positive correlation between estimated IQ and self-reported homosexual behaviour or identity.

Now I'm not sure what to make of this. He controlled for confounds such as race, religion and political orientation (and those correlations are interesting in themselves), but you can never measure and correct for everything in a study like this.

Kanazawa interprets all this in terms of the Savanna hypothesis, essentially the idea that intelligence allows us to transcend our evolutionary programming (according to which we ought to all be straight, amongst many other things) -

The Savanna-IQ Interaction Hypothesis (Kanazawa, 2010a), implies that the human brain’s difficulty with evolutionarily novel stimuli may interact with general intelligence, such that more intelligent individuals have less difficulty with [evolutionarily novel] stimuli than less intelligent individuals...

Evolutionarily novel entities that more intelligent individuals are better able to comprehend and deal with may include ideas and lifestyles that form the basis of their preferences and values; it would be difficult for individuals to prefer or value something that they cannot truly comprehend...

However, it could be that in America and the UK today, smarter people tend to end up in the kind of social circles where being gay is (for whatever reason) more acceptable.

My main problem with this is that the effects are very small. For example, in the AddHealth study, IQ in childhood was correlated with later adult sexual identity with a coefficent of 0.013... but the association of homosexuality with political attitude (liberalism) of 0.613, 60 times as high. (Edit: But these are unstandardized regression coefficients, so they cannot be directly compared. The coefficients represent the change in homosexuality per 'point' change in the other variable, but IQ varies more than political orientation, because political attitudes were measured on a 5 point scale in AddHealth but IQ has a mean of 100 points. Multiplying by the SD of the variables in question, which is one way to correct for this, gives a coefficient for IQ of 0.202 and for political attitude is 0.468, so intelligence is not as far behind politics as as I thought. Thanks to a reader for pointing that out and apologies for the error.)

The Savanna hypothesis is all very well, but does it predict such small effects? Isn't there a point where very weak evidence in favor of a theory actually becomes evidence against it...?

Kanazawa, S. (2012). Intelligence and Homosexuality Journal of Biosocial Science, 1-29 DOI: 10.1017/S0021932011000769

Beware Reverse Publication Bias

In all the fuss over the pressure for scientists to publish positive results, we may have been missing an equally dangerous kind of publication bias operating in the opposite direction.

So say Luijendijk and Koolman in the Journal of Clinical Epidemiology: The incentive to publish negative studies: how beta-blockers and depression got stuck in the publication cycle.

The background here is the possible link between beta blockers and depression. Beta blockers are drugs widely used to treat high blood pressure. Some studies have reported that they raise the risk of depression, though many others found no link. Propranolol is said by some to be the worst offender because it's best at entering the brain.

Luijendijk and Koolman say that beta blocker-depression studies have appeared in the form of "publication cycles" - first a positive study appears, and then negative ones follow. Then another study finds a positive link using a different method - and rebuttals, using those methods, soon appear. They sketch out several such positive-negative cycles based on different methods and particular hypotheses.

Now, there's two ways to look at this. You could explain this in terms of standard positive publication bias. Maybe lots of people looked into a possible link, the ones who found nothing didn't publish. Then someone, by chance, did find an association with depression, and they published it. Once that happens, the question became a hot topic so the unpublished negative studies were dusted off and submitted.

But there's a more worrying possibility. What if the original positive studies were correct, and the subsequent negative studies were the product of an inverse publication bias in favor of contrarian negative results?

The publication cycles in the literature about beta-blockers and depression seem to suggest that
the very publication of positive studies, whether true or false, increases the incentive to publish negative results, whether true or false... [in the case in question] the first as well as a significant number of subsequent negative studies were published in high-impact journals (8 of 19 journals with 2009 impact factor greater than 4.0). Third, power analysis showed thatd in two cycles, the first negative studies were underpowered...

If a true-positive study stimulated the publication of one or more false-negative studies, again an invalid picture of the true association would emerge. Publication of false-negative studies may thus give rise to publication bias, just like publication of false-positive studies. Research groups usually compete to get the first positive study published in a high-impact journal. It has been suggested that it could also be worthwhile to aim at getting the first study that challenges the former published.

This is not an entirely new idea. It was described in the classic Why Most Published Research Findings Are False, but only in passing.

To be honest it's impossible to know, in any particular case, whether inverse publication bias is at work. Depending upon whether you think beta blockers cause depression (and that's still controversial), your interpretation of the biases in the literature will probably differ.

However, I think the basic idea is important. Publication bias isn't a bias in favor of positive results per se. It's a bias towards "interesting" results - which in most cases means positive ones, but could equally well include negative ones, in certain contexts. In some ways, this could be a good thing, if the negative and positive biases eventually cancelled out, leaving a neutral playing field; but there's no guarantee that would ever happen.

As for how to fix publication bias - my opinions on that question are well known...

Luijendijk, H., and Koolman, X. (2012). The incentive to publish negative studies: how beta-blockers and depression got stuck in the publication cycle Journal of Clinical Epidemiology DOI: 10.1016/j.jclinepi.2011.06.022

The Evolutionary Psychology of Race, Beauty and Marriage

There are some papers that you can tell are going to be hot potatoes just from the titles. This is one of them: A Facial Attractiveness Account of Gender Asymmetries in Interracial Marriage.

Coming so soon after The Unconquered World, you'd be forgiven for thinking I am taking this blog in a more linkbaiting direction because I'm planning to introduce ads. I'm really not, it's just a coincidence.

The paper claims that white women are on average more attractive than black, while East Asians are prettier still.  For men, however, the positions were reversed (and the effects were even stronger.)

Saying that black women are on average less attractive than others was what got evolutionary psychologist and blogger Satoshi Kanazawa into spot of bother last year. The current paper agrees with Kanazawa on that point (though doesn't cite him)... although it also declares Kanazawa to be part of the least attractive race for males, so I don't know how happy he'll be about it.

Author Michael B. Lewis of Cardiff University took 600 Facebook photos "from people who were members of groups associated with further and higher education bodies either in the UK (for White faces), sub-Saharan Africa (for Black faces) and East Asia (for Asian faces)."

Photos with a "weird expression" and people who "looked" under 18 or over 30 were excluded. The actual ages were not checked. Hmm.

A panel of 40 British students (half male) were asked to rate all of the opposite-sex faces for attractiveness from 1 to 10. The ethnicity of the rater made no difference to the results but there were only 5 black and 6 Asian students out of 40 though:

After this we get some models proposing how these data might relate to British and American inter-racial marriage patterns, and some evolutionary speculation regarding why this might have evolved - Asia was cold so men were in short supply, that kind of thing - but that's all assuming the basic data are solid.

There are many possible objections to the methodology here, some of which are addressed in the paper, but there's one massive that isn't -

It's not stated how the Facebook images were gathered. All we're told is that "a research assistant" got the images from higher education institutions. Were they, consciously or subconsciously, picking photos that fitted the expected some pattern?

We're not told whether or not this individual was aware of the hypothesis of the study when they chose the pics. If they were aware, it's a fatal confound; (Edit - 19th Feb 2012 - The paper in fact says that the research assistant was "naive" i.e. that they were not aware of the hypothesis of the study, which is of course sound methodology. I missed this statement in the first version of this post.)

However, the broader point remains that they might have been selecting in line with their own preferences, or some other bias. Clearly, there's much room for cherry picking the examples, based on whether they "looked" too young or old, or had a "weird" expression...

Link: Also blogged about here.

Lewis, M. (2012). A Facial Attractiveness Account of Gender Asymmetries in Interracial Marriage PLoS ONE, 7 (2) DOI: 10.1371/journal.pone.0031703

Good Science, Bad History, in the British Journal of Psychiatry

The latest February 2012 issue of the British Journal of Psychiatry features a paper about the association between child abuse and later mental health problems. I haven't read it yet, but it looks pretty good.

However, it also includes an editorial from John Read and Richard Bentall which argues that:

Just 20 years ago, however, it would have been difficult to get the paper published. Mental health professions have been slow, even resistant, to recognise the role of childhood adversities in psychiatric disorder... Until very recently the hypothesis that abuse in childhood has a causal role in psychosis was regarded by many biologically oriented psychiatrists as heresy...

Really? I checked the BJP from exactly 20 years ago. The February 1992 issue contained:

• A paper about child sexual abuse in female psychiatric patients.
• A letter praising a different article, on the same topic.
• A review of 11 studies on psychosocial family interventions as treatments for schizophrenia.
• A paper looking at the effect of the social environment on symptoms of schizophrenia.

Four strikes and they're out. It's not true that this kind of thing wasn't being discussed 20 years ago.

Such grandstanding is bad for science. Few would deny that psychiatry in recent years has undervalued psychosocial factors and overvalued genetics and neuroscience, but it's actually quite a complicated story, not a Punch and Judy show with bad guys on one side and good guys on the other.

Rhetorical flourishes like this editorial certainly get attention but in the long run, down that road lies madness.

Read, J., and Bentall, R. (2012). Negative childhood experiences and mental health: theoretical, clinical and primary prevention implications The British Journal of Psychiatry, 200 (2), 89-91 DOI: 10.1192/bjp.bp.111.096727

Beware Good Theories

The ancient Greeks had a lovely theory. Certain places on the earth (caves, mostly) were, they thought, gateways to the underworld. Plants growing near these places could absorb the deadly essence of Hades and became poisonous.

Snakes and other venemous creatures got their poison by consuming these plants. And stinging insects got their little doses of poison by feeding off dead snakes.

Isn't that a great narrative? It explains everything, in a nice logical progression. OK, it presupposes what we would call a "supernatural" force as the ultimate origin of poison, but other than that, it's an entirely "scientific" account. In accordance with Occam's Razor, it proposes a single unified process underlying diverse phenomena.

It is, in other words, a perfect scientific theory. It's completely wrong, on every point, but we only know that because we now understand atoms, molecules, chemistry and biochemistry, which the Greeks had no way of knowing. At the time, the Hades theory was surely the best possible theory about where poison came from.

The moral of this story is, beware nice theories based on incomplete data.


Reference: Greek Fire, Poison Arrows and Scorpion Bombs, which I'm currently reading, all about chemical and biological weapons.

What Big Eyes You Have

According to the BBC, a new study has found that northern peoples have bigger eyes - and bigger brains.


Actually, the paper in question talked about eyes but didn't make much of the brain finding, which is confined to the Supplement. Nonetheless, they did find an effect on brain size too. Peoples living further from the equator have larger eye sockets and also larger total cranial capacity (brain volume), apparantly. The authors include Robin Dunbar of "Dunbar's Number" fame.

Their idea is that humans evolved larger eyes because further from the equator, there's on average less light, so you need bigger eyes to collect more light and see well.

They looked at 19th century skulls stored in museum collections, and measured the size of the eye sockets (orbits). They did this by filling them with a bunch of little glass balls and counting how many balls fit. They had a total of 73 "healthy adult" skulls from 12 different places, ranging from Scandinavia to Kenya.

Latitude essentially meant northern-ness because only one population (Australian Aborigines) were from far south of the equator.

Total brain size also increased with latitude, but eye size increased even faster, so the eye:brain ratio increased. They don't really discuss the brain size finding, except to suggest that it might be accounted for by increased visual cortex (though there's no direct evidence of that), but here it is, showing latitude vs. cranial capacity in ml.

The idea that northern peoples are brainier unfortunately has a long history. For example, it's been suggested that the coldness of northern climes meant that life was harder, so people evolved to be smarter to survive.

The heat of the Sahara was easy living compared to the deadly horrors of an English winter, in other words. Hmm.

The idea that higher latitudes are darker, so you'd need bigger eyes, and then a bigger brain (at least the visual parts of the brain) to process what you see, is certainly more plausible than that theory. However, the data in this paper seem pretty scanty.

Measuring skulls by filling them with little balls was cutting edge neuroscience in the 19th century. However, nowadays, we have MRI scanners. Although usually intended to image the brain, many MRI scans of the head also give an excellent image of the skull and eyes. Millions of people of all races get MRI scans every year.

Nowadays, people have medical records, so we can tell exactly how healthy people are. The people who became these skulls in a museum were said to be healthy, but how healthy a 19th century Indian or Kenyan could hope to be, by modern standards, I'm not sure. Certainly there's an excellent chance that they were malnourished and I suspect this would make your eyes and skull smaller.

Pearce, E., & Dunbar, R. (2011). Latitudinal variation in light levels drives human visual system size Biology Letters DOI: 10.1098/rsbl.2011.0570

Kanazawa's Black Day

Satoshi "The Scientific Fundamentalist" Kanazawa has suddenly become the most talked-about neuro/psychology blogger in the world, getting a BBC News article all to himself.


There's no need for the rest of us to feel jealous though. There may be no such thing as bad publicity, but I think that being accused of being a racist and a sexist who should be sacked, for something you wrote on your blog, something that swiftly got pulled, must come pretty close.

You can read the controversial article here, and in other places, because it was helpfully archived. It used to be here.

Kanazawa based his argument on the Add Health project which was a massive observational study of American adolescents and young adults.

Add Health is huge. It's produced over 3,000 scientific papers, presentations and other documents. That's because it collected a wealth of data on everything from genetics to blood chemistry to social relationships and emotional issues.

Kanazawa looked at the data on physical attractiveness. Attractiveness was rated by an interviewer. Each subject got interviewed for a couple of hours by one interviewer and at the end the interviewer rated how hot they found them.

The fateful post claimed that, according to the Add Health data, black women were rated less attractive, on average, than white, Asian and Native American ones. Let's assume that he's done his sums correctly and that this is true of the data.

The obvious problem is that maybe the interviewers were biased against black women, and rated them lower for that reason. Kanazawa didn't consider this in his post, which is unquestionably an oversight, but he did go on to speculate as to the biological reasons why they might be less attractive.

However, looking at the original Add Health data, can we check whether this bias was at play or not?

Short answer: I found no evidence either way.

Long answer: I first looked over the Add Health website but it doesn't seem to mention anything about who the interviewers were. It doesn't mention their own ethnicity, which would be helpful, although even if they were all black themselves, they might have internalized racism, so that wouldn't be conclusive. They were trained, but then, you can't train someone to not be a racist.

Then I decided to look at the publications. I searched Google Scholar for "Add Health" + attractiveness. This reveals a number of articles, including a 2007 one by Kanazawa ironically, but only one seemed really relevant: Weight Preoccupation as a Function of Observed Physical Attractiveness. (There are other hits, but I skimmed the most likely looking ones and they didn't address bias.)

The details are unimportant, but it involved race and attractiveness, so the authors had to deal with the question of potential rater bias. Unlike Kanazawa they didn't just brush this under the carpet:

Although the interviewers were different races and ethnicities, there is no information about the race or ethnicity of the interviewer for any one respondent to examine systematic bias.

However, post hoc cluster analyses that controlled for an interviewer effect yielded similar results; thus, it is unlikely that interviewers had any substantial biases against any one ethnic group or that they rated attractiveness significantly differently from each other.

The point about "post-hoc cluster analysis" is the key here. To try to control for rater effects (not just racial ones) they analyzed the data covarying for which interviewer rated each girl. They didn't know what races the interviewers were, but they did know which girls got rated by the same interviewer. They found that controlling for the rater did not affect their results.

So does that mean there was no bias? No. Because - this only applies to their results, which were not about attractiveness per se, but about the interaction of attractiveness with other factors to predict an outcome variable (dieting and concern about weight) within a given race.

Even supposing that half of the raters were KKK members who cruelly subtracted, say, a million points from the rated attractiveness of any given black subject, so long as they still rated some black subjects as more attractive than others, all of the comparisons within the black subjects would still work fine: the millions would all cancel out.

So in my judgement, we just can't tell. Unless I've missed something, in which case, please tell us about it in the comments.

Left Wing vs. Right Wing Brains

So apparently: Left wing or right wing? It's written in the brain

People with liberal views tended to have increased grey matter in the anterior cingulate cortex, a region of the brain linked to decision-making, in particular when conflicting information is being presented...

Conservatives, meanwhile, had increased grey matter in the amygdala, an area of the brain associated with processing emotion.

This was based on a study of 90 young adults using MRI to measure brain structure. Sadly that press release is all we know about the study at the moment, because it hasn't been published yet. The BBC also have no fewer than three radio shows about it here, here and here.

Politics blog Heresy Corner discusses it...

Subjects who professed liberal or left-wing opinions tended to have a larger anterior cingulate cortex, an area of the brain which, we were told, helps process complex and conflicting information. (Perhaps they need this extra grey matter to be able to cope with the internal contradictions of left-wing philosophy.)

This kind of story tends to attract chuckle-some comments.

In truth, without seeing the full scientific paper, we can't know whether the differences they found were really statistically solid, or whether they were voodoo or fishy. The authors, Geraint Rees and Ryota Kanai, have both published a lot of excellent neuroscience in the past, but that's no guarantee.

In fact, however, I suspect that the brain is just the wrong place to look if you're interested in politics, because most political views don't originate in the individual brain, they originate in the wider culture and are absorbed and regurgitated without much thought. This is a real shame, because all of us, left or right, have a brain, and it's really quite nifty:

But when it comes to politics we generally don't use it. The brain is a powerful organ designed to help you deal with reality in all its complexity. For a lot of people, politics doesn't take place there, it happens in fairytale kingdoms populated by evil monsters, foolish jesters, and brave knights.

Given that the characters in this story are mindless stereotypes, there's no need for empathy. Because the plot comes fully-formed from TV or a newspaper, there's no need for original ideas. Because everything is either obviously right or obviously wrong, there's not much reasoning required. And so on. Which is why this happens amongst other things.

I don't think individual personality is very important in determining which political narratives and values you adopt: your family background, job, and position in society is much more important.

Where individual differences matter, I think, is in deciding how "conservative" or "radical" you are within whatever party you find yourself. Not in the sense of left or right, but in terms of how keen you are on grand ideas and big changes, as opposed to cautious, boring pragmatism.

In this sense, there are conservative liberals (i.e. Obama) and radical conservatives (i.e. Palin), and that's the kind of thing I'd be looking for if I were trying to find political differences in the brain.

Links: If right wingers have bigger amygdalae, does that mean patient SM, the woman with no amygdalae at all, must be a communist? Then again, Neuroskeptic readers may remember that the brain itself is a communist...

XMRV - Innocent on All Counts?

A bombshell has just gone off in the continuing debate over XMRV, the virus that may or may not cause chronic fatigue syndrome. Actually, 4 bombshells.

A set of papers out today in Retrovirology (1,2,3,4) claim that many previous studies claiming to have found the virus haven't actually been detecting XMRV at all.

Here's the rub. XMRV is a retrovirus, a class of bugs that includes HIV. Retroviruses are composed of RNA, but they can insert themselves into the genetic material of host cells as DNA. This is how they reproduce: once their DNA is part of the host cell's chromosomes, that cell is ends up making more copies of the virus.

But there are lots of retroviruses out there, and there used to be yet others that are now extinct. So bits of retroviral DNA are scattered throughout the genome of animals. These are called endogenonous retro-viruses (ERVs).

XMRV is extremely similar to certain ERVs found in the DNA of mice. And mice are the most popular laboratory mammals in the world. So you can see the potential problem: laboratories all over the world are full of mice, but mouse DNA might show up as "XMRV" DNA on PCR tests.

Wary virologists take precautions against this by checking specifically for mouse DNA. But most mouse-contamination tests are targeted at mouse mitochondrial DNA (mtDNA). In theory, a test for mouse mtDNA is all you need, because mtDNA is found in all mouse cells. In theory.

Now the four papers (or are they the Four Horsemen?) argue, in a nutshell, that mouse DNA shows up as "XMRV" on most of the popular tests that have been used in the past, that mouse contamination is very common - even some of the test kits are affected! - and that tests for mouse mtDNA are not good enough to detect the problem.

• Hue et al say that "Taqman PCR primers previously described as XMRV-specific can amplify common murine ERV sequences from mouse suggesting that mouse DNA can contaminate patient samples and confound specific XMRV detection." They go on to show that some human samples previously reported as infected with XMRV, are actually infected with a hybrid of XMRV and a mouse ERV which we know can't infect humans.
• Sato et al report that PCR testing kits from Invitrogen, a leading biotech company, are contaminated with mouse genes including an ERV almost identical to XMRV, and that this shows up as a false positive using commonly used PCR primers "specific to XMRV".
• Oakes et al say that in 112 CFS patients and 36 healthy control, they detected "XMRV" in some samples but all of these samples were likely contaminated with mouse DNA because "all samples that tested positive for XMRV and/or MLV DNA were also positive for the highly abundant IAP long terminal repeat [found only in mice] and most were positive for murine mitochondrial cytochrome oxidase sequences [found only in mice]"
• Robinson et al agree with Oakes et al: they found "XMRV" in some human samples, in this case prostate cancer cells, but they then found that all of the "infected" samples were contaminated with mouse DNA. They recommend that in future, samples should be tested for mouse genes such as the IAP long terminal repeat or cytochrome oxidase, and that researchers should not rely on tests for mouse mtDNA.

They're all open-access so everyone can take a peek. For another overview see this summary published alongside them in Retrovirology.

I lack the technical knowledge to evaluate these claims, no doubt plenty of people will be rushing to do that before long. (Update: The excellent virologyblog has a more technical discussion of these studies.) But there are a couple of things to bear in mind.

Firstly, these papers cast doubt on tests using PCR to detect XMRV DNA. However, they don't have anything to say about studies which have looked for antibodies against XMRV in human blood, at least not directly. There haven't been many of these, but the paper which started the whole story, Lombardi et al (2009), did look for, and found, anti-XMRV immunity, and also used various other methods to support the idea that XMRV is present in humans. So this isn't an "instant knock-out" of the XMRV theory, although it's certainly a serious blow.

Secondly, if the 'mouse theory' is true, it has serious implications for the idea that XMRV causes chronic fatigue syndrome and also for the older idea that it's linked to prostate cancer. But it still leaves a mystery: why were the samples from CFS or prostate cancer patients more likely to be contaminated with mouse DNA than the samples from healthy controls?

Robert A Smith (2010). Contamination of clinical specimens with MLV-encoding nucleic acids: implications for XMRV and other candidate human retroviruses Retrovirology : 10.1186/1742-4690-7-112

Wikileaks: A Conversation

"Wikileaks is great. It lets people leak stuff."

"Hang on, so you're saying that no-one could leak stuff before? They invented it?"

"Well, no, but they brought leaking to the masses. Sure, people could post documents to the press before, but now anyone in the world can access the leaks!"

"Great, but isn't that just the internet that did that? If it weren't for Wikileaks, people could just upload their leaks to a blog. Or email them to 50 newspapers. Or put them on the torrents. Or start their own site. If it's good, it would go viral, and be impossible to take down. Just like Wikileaks, with all their mirrors, except even more secure, because there'd be literally no-one to arrest or cut off funding to."

"OK, but Wikileaks is a brand. It's not about the technical stuff - it's the message. Like one of their wallpapers says, they're synonymous with free speech."

"So you think it's a good thing that one organization has become synonymous with the whole process of leaking? With the whole concept of openness? What will happen to the idea of free speech, then, if that brand image suddenly gets tarnished - like, say, if their founder and figurehead gets convicted of a serious crime, or..."

"He's innocent! Justice for Julian!"

"Quite possibly, but why do you care? Is he a personal friend?"

"It's an attack on free speech!"

"So you agree that one man has become synonymous with free speech? Doesn't that bother you?"

"Erm... well. Look, fundamentally, we need Wikileaks. Before, there was no centralized system for leaking. Anyone could do it. It was a mess! Wikileaks put everything in one place, and put a committee of experts in a position to decide what was worth leaking and what wasn't. It brought much-needed efficiency and respectability to the idea of leaking. Before Wikileaks, it was anarchy. They're like... the government."

"..."

Edit: See also The Last Psychiatrist's take.

Online Comments: It's Not You, It's Them

Last week I was at a discussion about New Media, and someone mentioned that they'd been put off from writing content online because of a comment on one of their articles accusing them of being "stupid".

I found this surprising - not the comment, but that anyone would take it so personally. It's the internet. You will get called names. Everyone does. It doesn't mean there's anything wrong with you.

I suspect this is a generational issue. People who 'grew up online' know, as Penny Arcade explained, that

The sad fact is that there are millions of people whose idea of fun is to find people they disagree with, and mock them. And they're right, it can be fun - why else do you think people like Jon Stewart are so popular? - but that's all it is, entertainment. If you're on the receiving end, don't take it seriously.

If you write something online, and a lot of people read it, you will get slammed. Someone, somewhere, will disagree with you and they'll tell you so, in no uncertain terms. This is true whatever you write about, but some topics are like a big red rag to the herds of bulls out there.

Just to name a few, if you say anything vaguely related to climate change, religion, health, the economy, feminism or race, you might as well be holding a placard with a big arrow pointing down at you and "Sling Mud Here" on it.

The point is - it's them, not you. They are not interested in you, they don't know you, it's not you. True, they might tailor their insults a bit; if you're a young woman you might be, say, a "stupid girl" where a man would merely get called an "idiot". But this doesn't mean that the attacks are a reflection on you in any way. You just happen to be the one in the line of fire.

What do you do about this? Nothing.

Trying to enter into a serious debate is pointless. Insulting them back can be fun, just remember that if you find it fun, you've become one of them: "he who stares too long into the abyss...", etc. Complaining to the moderators might help, but unless the site has a rock solid zero-tolerance-for-fuckwads policy, probably not. Where the blight has taken root, like Comment is Free, I'd not waste your time complaining. Just ignore it and carry on.

The most important thing is not to take it personally. Do not get offended. Do not care. Because no-one else cares. Especially the people who wrote the comments. They presumably care about whatever "issue" prompted their attack, but they don't care about you. If anything, you should be pleased, because on the internet, the only stuff that doesn't attract stupid comments is the stuff that no-one reads.

I've heard these attacks referred to as "policing" existing hierarchies or "silencing" certain types of people. This seems to me to be granting them far more respect than they deserve. With the actual police, if you break the rules, they will physically arrest you. They have power. Internet trolls don't: if they succeed in policing or silencing anybody, it's because their targets let them boss them around. They're nobody; they're not your problem.

If you can't help being offended by such comments, don't read them, but ideally you shouldn't need to resort to that. For one thing, it means you miss the sensible comments (and there's always a few). But fundamentally, you shouldn't need to do this, because you really shouldn't care what some anonymous joker from the depths of the internet thinks about you.

The Tree of Science

How do you know whether a scientific idea is a good one or not?


The only sure way is to study it in detail and know all the technical ins and outs. But good ideas and bad ideas behave differently over time, and this can provide clues as to which ones are solid; useful if you're a non-expert trying to evaluate a field, or a junior researcher looking for a career.

Today's ideas are the basis for tomorrow's experiments. A good idea will lead to experiments which provide interesting results, generating new ideas, which will lead to more experiments, and so on.

Before long, it will be taken as granted that it's true, because so many successful studies assumed it was. The mark of a really good idea is not that it's always being tested and found to be true; it's that it's an unstated assumption of studies which could only work if it were true. Good ideas grow onwards and upwards, in an expanding tree, with each exciting new discovery becoming the boring background of the next generation.

Astronomers don't go around testing whether light travels at a finite speed as opposed to an infinite one; rather, if it were infinite, their whole set-up would fail.

Bad ideas generate experiments too, but they don't work out. The assumptions are wrong. You try to explain why something happens, and you find that it doesn't happen at all. Or you come up with an "explanation", but next time, someone comes along and finds evidence suggesting the "true" explanation is the exact opposite.

Unfortunately, some bad ideas stick around, for political or historical reasons or just because people are lazy. What tends to happen is that these ideas are, ironically, more "productive" than good ideas: they are always giving rise to new hypotheses. It's just that these lines of research peter out eventually, meaning that new ones have to take their place.

As an example of a bad idea, take the theory that "vaccines cause autism". This hypothesis is, in itself, impossible to test: it's too vague. Which vaccines? How do they cause autism? What kind of autism? In which people? How often?

The basic idea that some vaccines, somewhere, somehow, cause some autism, has been very productive. It's given rise to a great many, testable, ideas. But every one which has been tested has proven false.

First there was the idea that the MMR vaccine causes autism, linked to a "leaky gut" or "autistic enterocolitis". It doesn't, and it's not linked to that. Then along came the idea that actually it's mercury preservatives in vaccines that cause autism. It doesn't. No problem - maybe it's aluminium? Or maybe it's just the Hep B vaccine? And so on.

At every turn, it's back to square one after a few years, and a new idea is proposed. "We know this is true; now we just need to work out why and how...". Except that turns out to be tricky. Hmm. Maybe, if you keep ending up back at square one, you ought to find a new square to start from.

Israel and Palestine are Both Fighting Back...?

There are three basic schools of thought on the Israel / Palestine thing.

• Those evil Israelis are out to destroy Palestine, and the Palestinians are just fighting back.
• Those evil Palestinians are out to destroy Israel, and the Israelis are just fighting back.
• It's a cycle of violence, where both sides are fighting back against the other.
  

Which one you subscribe to depends mostly on where you were born. I'm not aware of many people who've changed their minds on this issue, perhaps because doing so would require a study of the last 2,500 years of history, religion and politics.

Wouldn't it be handy if science could provide an answer? According to the authors of a new paper in Proceedings of the National Academy of Science, the "cycle" school is right: both sides are fighting back against the other: Both sides retaliate in the Israeli-Palestinian conflict.

The authors (from Switzerland, Israel and the USA) took data on daily fatalities on both sides, and also of daily launches of Palestinian "Qassam" rockets at Israel. The data run from 2001, the start of the current round of unpleasantness, to late 2008, the Gaza War.

They looked to see whether the number of events that happened on a certain day predicted the number of events caused by the other side on the following days, i.e. whether a Palestinian death caused the Palestinians to retaliate by firing more rockets and killing more Israelis, and vice versa.

What happened? They found that both sides were more likely to launch attacks on the days following a death on their own side. The exception to this rule was that Israel did not noticeably retaliate against Qassam launches. This is perhaps because Qassams are so ineffective: out of 3,645 recorded launches, they killed 15 people.

These graphs show the number of "extra" actions on the days following a event, averaged over the whole 8 years, according to a statistical method called the Impulse Response Function. Note that the absolute size of the effects is larger for the Israeli retaliations (the Y axis is bigger); there were a total of 4,874 Palestinian fatalities and 1,062 Israeli fatalities

The authors then used another method called Vector Autoregression to discover more about the relationship. In theory, this method controls for the past history of actions by a given side, so that it reveals the number of actions independently caused by the opposing side.

the number of Qassams fired increases by 6% on the first day after a single killing of a Palestinian by Israel; the probability of any Qassams being fired increases by 11%; and the probability of any Israelis being killed by Palestinians increases by 10%. Conversely, 1 day after the killing of a single Israeli by Palestinians, the number of Palestinians killed by Israel increases by 9%, and the probability of any Palestinians being killed increases by 20%

....retaliation accounts for a larger fraction of Palestinian compared with Israeli aggression: in the levels specification, 10% of all Qassam rockets can be attributed to prior Israeli attacks on Palestinians, but only 4% of killings of Palestinians by Israel can be attributed to prior Palestinian attacks on Israel.... 6% of all days on which Palestinians attack Israel with rockets, and 5% of all days on which they attack by killing Israelis, can be attributed to retaliation; in contrast, this is true for only 2% of all days on which Israel kills Palestinians.

What are we to make of this? This is a good paper as far as it goes, and it casts doubt on earlier analyses finding that Israel is retaliating against Palestinians but not vice versa. However, the inherent problem with all of this research (beyond the fact that it's all based on correlations and can only indirectly imply causation), is that it focuses on individual acts of violence. The authors say, citing surveys, that

Over one half of Israelis and three quarters of Palestinians think the other side seeks to take over their land. When accounting for their own acts of aggression, Israelis often claim to be merely responding to Palestinian violence, and Palestinians often see themselves as simply reacting to Israeli violence.

But I don't think many Israelis would argue that the IDF only kills individual Palestinians as a reflex reaction to a particular attack. They're claiming that the whole conflict is a defensive one, that the Palestinians are the aggressors, but that doesn't rule out their taking the initiative on a tactical level e.g. in destroying Palestinian military capabilities before they have a chance to attack. And vice versa on the other side.

WW2 was a war of aggression by the Axis powers, but that doesn't mean that the Allies only killed Axis soldiers after they'd attacked a certain place. The Allies were on the offensive for the second half of the war, and eventually invaded the Axis's own homelands, but it was still a defensive war, because the Axis were responsible for it.

For Israel and for Palestine, the other guys are to blame for the whole thing. Who's right, if anyone, is fundamentally a historical, political and ethical question, that can't be answered by looking at day-to-day variations in who's shooting when.

Comment Policy: Please only comment if you've got something to say about this paper, or related research. Comments that are just making the case for or against Israel will get deleted.

Haushofer J, Biletzki A, & Kanwisher N (2010). Both sides retaliate in the Israeli-Palestinian conflict. Proceedings of the National Academy of Sciences of the United States of America PMID: 20921415