What Is Science?

The other day I was in a discussion about what "science" is. I've written about this before but this debate got me thinking about it again and I thought I'd set out what I think in more detail.

I wasn't sure how best to structure this so I'm going to start with my main claim, followed by a Q and A bit. The Q's are not intended to be straw-men or caricatures, they're questions I've asked myself in the course of thinking about this.

My Claim: "Science" is just the process of looking at the world and thinking about the evidence in an effort to understand it. It's not a special form of knowledge, scientists don't use a special 'scientific method' - scientists just look and think about things. They may use special equipment and techniques, but in essence it's no different to what we all do every day. As such it makes no sense to talk about the 'limits of science' or 'what science can't tell us', unless by that we mean the limits of human knowledge itself, because science just is knowledge.

Q: "But if science were just observation, everyone would be a scientist and it becomes meaningless." - No: for the same reason that not everyone is a poet, even though anyone can write a poem.

Science is observation informed by previous scientific findings i.e. it is expert observation. Anyone can, say, look at the stars but this doesn't make them an astronomer. Astronomy is in essence just looking at the stars and thinking about them - in a broad sense - but to contribute to astronomy, you first need to know the relevant background, which few except astronomers do.

Likewise, anyone can write a poem, but few of us can make a living out of it.

Q: "OK, but still, if science is just observation, then all forms of knowledge are science." - This is a tricky one, but the answer is crucial to understanding my point.

A few hundred years ago, the word "science" in English did indeed just mean "knowledge". However, more recently, it has come to mean a particular subset of knowledge: roughly, it today includes physics + chemistry + biology. Maybe some others.

We lump these three (or more) things together and call the lump "science". But this lump is more or less arbitrary. Physics + chemistry + biology don't share a special essence, which sets them apart from other kinds of knowledge (other 'sciences' in the older sense.)

So I'm not saying that all knowledge is "science" in the modern sense. The modern word "science" only includes a limited portion of knowledge. But I am saying that the rest of knowledge is essentially no different from science, because "science" is just an arbitrary subset of knowledge.

Here's a picture of what I mean:

Or here's an analogy. The color spectrum has infinite different shades. We conventionally divide it up into "red", "orange", "yellow" etc. and that's fine for most purposes. But there is no essential difference between "orange" and "yellow" and no clear dividing line: they are just collections of shades.

Science is a colour of knowledge. It's not a true kind.

Q: "But if the difference between science and knowledge is arbitrary, are you saying that The Scientific Method is the only way to knowledge?" Not at all. I don't think 'The Scientific Method' exists.

This follows from the fact that "science" is an arbitrary lump. Scientists are a diverse bunch and they use many different methods. Theoretical physicists, for example, use methods which are very close to those of mathematicians - who are not 'scientists' by most definitions. Zoologists use others, and you can get by in (most) of zoology without knowing any math at all. And so on.

In fact, there's almost as much difference between branches of "the same science" as there is between sciences. Just like "science", "biology" is a lump of diverse things, although not quite as arbitrary a lump.

Outside science, people use all kinds of methods as well. Historians have their set of methods, economists have others, all tailored to the particular demands of the case. That's exactly how it should be - all knowledge comes from observation and, to observe different things, you need different methods.

There are many different kinds of facts, but a fact is a fact, whether it's a scientific fact, a historical fact, or just an everyday fact. "Shakespear wrote Hamlet" is just as true as "The earth orbits the sun" is just as true as "It's raining" (if it is, in fact, raining.) The facts of history are just as true as the facts of biology.

But there is a grain of truth in the question here: I am saying that observation is the only way to knowledge.

Q: "That's very simplistic. Are you saying that we can only know what we can see and measure?" - No because I'm using "observe" in the broadest sense here, to include things like noticing, sensing, feeling, seeing, hearing, being told that, reading about...

You observe that it's raining: maybe you look out the window, maybe you hear the rain on the roof, maybe someone comes in from outside dripping wet. You observe that you feel hungry. You observe that Obama is president (even if you've never actually seen him) by watching the news. Etc.

"Observe" is in many cases an awkward word and I'm not saying we should use it in all those cases. My point is that these are all ways of finding stuff out about the world. In that broad sense, I think all knowledge comes from observation - although maybe indirectly, through thinking about observations; thoughtless observation is almost as unhelpful as purely abstract speculation.

Of course, it's easier said than done: very often it's not clear what we've observed (is it real or some kind of trick, mistake, illusion?), what it means, whether it matters, or even what the question is. This is why there's always room for debate, controversy and doubt, at least at first, before all the observations have been made.

Q: "But what you're saying is merely trite and obvious: 'science is based on observation' 'there is no one single scientific method', well, duh!" - From a certain perspective, they are obvious, but if you think so, then you ought to agree with everything else I've written here. They're all connected, you can't take some and leave the rest.

Autoerotic Asphyxiation For Science

The death of an autoerotic asphyxiation fan ended up providing science with some valuable observations of what happens during choking

On Twitter recently, I've been highlighting some really bad ideas courtesy of the medical literature. From injecting vaseline into your own penis, to pumping compressed air up your rectum for a joke, people have tried it and they've ended up on PubMed as a result.

But a recent paper details an extreme case. Canadian medics Anny Sauvageau and colleagues report on the life and death of a 35 year old Hispanic man who, we're told,

filmed several of his autoerotic asphyxia sessions. After his accidental hanging death, several films were found at the scene, including 3 filmed nonlethal ligature strangulations.

In these 3 ligature strangulations, the man is sitting on a chair. A pair of pajama pants is rolled once around his neck, with the extremities of the pants falling down on each side of his chest. The man is pulling the extremities of the pants with both hands to apply compression on his neck. After losing consciousness, he ceases to pull on the ligature, and the pants slowly loosen around the neck. A few seconds later, he regains consciousness and gets up from the chair.

The videos - which before you go and look, are not included as Supplementary Materials - are of scientific interest, because they offer a rare glimpse into what happens during human strangulation.

You might think that given that people have been strangling each other for thousands of years, it would be a well-understood phenomenon, but in fact it's very difficult to study. Most of the available evidence comes from video recordings of execution by hanging, but there are only perhaps 10 of these records on file. Although there's also been an interesting line of research involving judo, in which judo masters apply choke holds to willing volunteers. These include one remarkable paper in which brain activity was recorded before, during and after.

Anyway, for what it's worth, this is what seems to happen during strangulation, including hanging:

1. Loss of consciousness (10 +- 3 seconds).
2. Convulsions: (14 +- 3 seconds).
3. Decerebrate rigidity: (19 +- 5 seconds)
4. Start of very deep respiratory attempt (19 +- 5 seconds)
5. Decorticate rigidity (38 +- 15 seconds)
6. Loss of muscle tone (1 minute 17 seconds +- 25 seconds)
7. End of the very deep respiratory attempt (1 minute 51 seconds +- 30 seconds)
8. Last muscle movement (4 minutes 12 seconds +- 2 minutes 29 seconds)

The man in this case took himself to Stage 2 before recovering.

Until the last time he tried it, when he didn't.

Sauvageau A, Ambrosi C, and Kelly S (2012). Three Nonlethal Ligature Strangulations Filmed by an Autoerotic Practitioner: Comparison of Early Agonal Responses in Strangulation by Ligature, Hanging, and Manual Strangulation. The American journal of forensic medicine and pathology PMID: 22922552

Beyond Self-Report

If you want to learn about someone, should you ask them?

Two bits of research published recently cast doubt on the validity of self-report as a tool in psychology and psychiatry. The first found that teens who reported that they suffered from bullying experienced more mild 'psychotic-like' symptoms. That correlation would be consistent with the idea that these symptoms arise as a response to stress.

However - the same study found that there was absolutely no correlation between peer ratings of whether someone was bullied, and their psychotic symptoms. Only self-report was associated.

The second study looked at whether a crisis intervention program - intensive mental health care - helped people who'd recently attempted suicide. The results showed that, compared to a control condition, suicidal patients who got crisis care self-reported fewer subsequent suicide attempts.

But a trawl of hospital records painted exactly the opposite picture - the intervention group were more likely to end up in hospital with a second attempt.

Remarkably few studies in psychology and psychiatry compare self-report to other measures of behaviour. This is because self-report is typically a lot easier. If these papers are anything to go by, however, this is a serious limitation. Self-report can be radically at odds with other measures of behaviour.

Which raises the question - who's right? Are the self-reports right, when they clash with other sources? I don't think there's an easy answer. In the bullying case, it might be that self-report is more accurate, because the peers doing the peer-report are the bullies. In the suicide study, maybe the self-report was more accurate, because the patients knew about attempts that never made it to hospital.

But on the other hand you could argue exactly the opposite. Maybe the self-reports of bullying just reflected whether the kids thought their classmates liked them. Maybe the patients were ashamed to admit that they'd reattempted suicide even though they'd got all this special crisis care. It's hard to tell.

One thing's clear though: self-report is not the whole story.

Gromann PM, Goossens FA, Olthof T, Pronk J, and Krabbendam L (2012). Self-perception but not peer reputation of bullying victimization is associated with non-clinical psychotic experiences in adolescents. Psychological medicine, 1-7 PMID: 22895003 

Morthorst B, Krogh J, Erlangsen A, Alberdi F, and Nordentoft M (2012). Effect of assertive outreach after suicide attempt in the AID (assertive intervention for deliberate self harm) trial: randomised controlled trial. BMJ (Clinical research ed.), 345 PMID: 22915730

Replication Alone Is Not Enough

Psychology has lately been hit by high-profile fraud scandals, and broader concerns over questionable research practices. Now the Society for Personality and Social Psychology (SPSP) has released a statement on "Responsible Conduct", and a task force has produced a report.

This is a start, and the SPSP is to be commended for facing up these problems (which affect many other fields) relatively early. However, neither of their documents contains much meat in my view.

Point One on the task force report is that "Replication is the key to building our science" and they suggest a "web site for depositing replications and failures to replicate" - but don't mention that various enterprising researchers have already made one. Nor do they tip their hats to the Open Science Initiative addressing just this issue. This makes me worried that they're planning to reinvent the wheel.

More fundamentally I disagree that replication is key to psychology or any field. Our goal should be replicability. Failure to replicate findings is a symptom of problems with those original findings, rather than being a problem in and of itself. Good results replicate; we want better results to be published.

In other words, we should strike at the root cause of invalid research, namely, the perverse incentives towards publishing as many eye-catching positive results with p values below 0.05 as possible by any means necessary. P-value fishing, selective reporting, post-hoc "prior hypotheses" and other questionable practices are a large part of what make unreplicable results.

We should encourage replication, but it's no panacea.

An overemphasis on replication, without addressing the incentives, could actually harm science. It could lead to scientists spending all their time worrying about the political drama of who's replicating who and why, and which questionable practices they can use to replicate their friends' data - rather than actually doing science.

This is why we shouldn't be satisfied with any reform effort that puts replication before replicability. If you can fudge a result, you can fudge the data a replication. How to fight questionable practices is another question but I've proposed reforms that I think would work, namely pre-registration of hypotheses, methods, and statistical analyses. Others have their own ideas.

A lesson from clinical medicine here. Clinical trials of new drugs adopted pre-registration, but only after they tried replication and it didn't work. Pharmaceutical regulators have long required multiple demonstrations of drug efficacy. One trial was not enough. Sounds good - but the problem was that drug companies just did lots of trials and analyses, picked the positive ones, and used them.

So in summary: replication is important, and we don't do enough of it, but replication alone is not enough to fix psychology.

Neuroscience: Solving The Hard-On Problem

Take a good look at this, fellas:

It might not look like much, but this is science's very first glimpse of something rather close to the hearts of most men.

These images show nerve activation in the spinal cord during sexual arousal. Using functional magnetic resonance imaging (fMRI), best known as a way of recording brain activity, applied to the spine, Canadian researchers Kozyrev et al were able to record the changes associated with, well, stimulation. Here's the paper: Neural correlates of sexual arousal in the spinal cords of able-bodied men.

The methods sound like a real riot. Ten guys were scanned while being exposed to two different kinds of stimulation. First, 'audiovisual'

Films, depicting heterosexual couples engaged in sex play, vaginal sexual intercourse, and oral sex, were presented in two 5-min blocks, separated by a baseline condition (blank screen) for 3 min... The selected films were chosen by the investigators and were all very highly rated (on a scale of 1 to 10) by independent viewers. Only films that received a minimum score of 8 out of 10 were shown to participants.

They don't say who these independent grumble-rating viewers were, but I'm, er, told that some porn sites these days have user ratings next to each clip. So it's possible that they used those and that the raters were, quite literally, just some bunch of wankers.

As for the manual stimulation...

All participants manually performed stimulation of the penis. Participants received written instructions superimposed onto a rear-projection screen, indicating whether to rest or to perform penile self-stimulation... there were two equal blocks of 1.5 min of stimulation that were separated by a 1.5-min block of rest... a shorter duration was selected for this part of the study in order to avoid overstimulation of the penis and/or ejaculation.

Good thinking. That could have been messy.

The results of the study largely confirmed previous work, but it's an important step forward because until now, no-one had measured arousal-related spinal activation directly in healthy humans; the evidence came from recordings in animals and spinal injury patients.

Clearly there's more work to be done here. The images are rather crude. That grey oval is meant to look like this:

Still, it's early days. Spinal cord fMRI is not a new technique, having first been performed in 1999, but it's not received nearly as much research interest as the brain variety.

Kozyrev N, Figley CR, Alexander MS, Richards JS, Bosma RL, & Stroman PW (2012). Neural correlates of sexual arousal in the spinal cords of able-bodied men: a spinal FMRI investigation. Journal of sex & marital therapy, 38 (5), 418-35 PMID: 22900624

Psychiatrists: Does Fire Put Out Fire?

If you're trying to fight fire, should you use fire?

This, pretty much, is the question asked by a group of psychiatrists in a new paper: Will disruptive mood dysregulation disorder (DMDD) reduce false diagnosis of bipolar disorder in children?

The background here is that there's growing concern that bipolar disorder, previously thought to be extremely rare in prepubescent children, is now being diagnosed, inappropriately, in children - specifically in American children. This epidemic of so-called "pediatric bipolar disorder" (PBD) shows no signs of abating.

In response to these concerns, the proposed new fifth edition of the Diagnostic and Statistical Manual (DSM-5) is slated to introduce a new disorder - DMDD. The stated purpose of DMDD is to prevent children getting a diagnosis of PBD - but only by giving them another diagnosis instead.

As I said in 2010 (note, TDDD is the old name of DMDD)

We can all sympathize with the sentiment behind TDDD - but this is fighting fire with fire. Is the only way to stop kids getting one diagnosis, to give them another one? ... Can't we just decide to diagnose people less? Apparently, that would be a rather too radical change...

Now, according to the authors of the new paper, if DMDD becomes an official diagnosis, it would only slightly reduce the number of PBD diagnoses - and

If indeed DMDD is a true entity, we suspect that, like bipolar disorder, it, too, will be overdiagnosed.

This was based on a study of 82 kids who were admitted to a specialist children's psychiatric hospital. Of the children, 30% met DMDD criteria based on parental report - but only half of those diagnoses were confirmed by observation of the child'd behaviour in hospital. Parents, in other words, over-rated DMDD symptoms. A rigorous DMDD diagnosis would only "save" a minority of children from a PBD diagnosis.

Even in those cases where "DMDD" seems most justified, it's really not clear who would benefit from giving them another diagnosis because they always qualified for 3 or more other diagnoses. Take a look at this table, showing the frankly ridiculous array of "different" disorders diagnosed in 12 children - the ones who were rated most likely to be "bipolar" by parental report -

Many parents reported "bipolar" symptoms but only 2 of 12 were judged to be actually bipolar; those two incidentally were aged 11 and 12 - consistent with the old view that bipolar is very rare before puberty.

So even if DMDD is a marginally better diagnosis than PBD - do we really need to give out any more diagnoses to kids like this?

The funny thing is that overdiagnosis of PBD is just about the only concern that the DSM-V committee is responding to at all. There are plenty of other well-publicized concerns: overdiagnosis of ADHD, overdiagnosis of depression... most of these are about overdiagnosis to be honest. Anyway, in those cases, DSM-V is proposing to either do nothing much, or actually expand the diagnostic criteria.

For PBD, they are at least trying, so perhaps they deserve some points for effort.

Margulies DM, Weintraub S, Basile J, Grover PJ, and Carlson GA (2012). Will disruptive mood dysregulation disorder reduce false diagnosis of bipolar disorder in children? Bipolar disorders, 14 (5), 488-96 PMID: 22713098

Is Poker A Game of Skill or Luck?

Success in poker is all about luck, according to researchers at the University of Bremen, Germany: Is Poker a Game of Skill or Chance? A Quasi-Experimental Study.

I'm not a gambling man, but I'll bet this is going to be a controversial study.

The authors recruited 300 poker players - half were defined as 'experts' and the rest were  'average'. Players sat at tables of 6, with 3 experts and 3 average per table, and played 60 hands of Texas Hold 'em. On some tables, there was a fixed limit, on others, no limit. The stakes were fairly small, with each player having just 10 euros to start with, but there were also prizes of up to 500 euros (over $600) for the overall winner.

The trick was that the deals were fixed, with some players getting better cards than others. This was to allow the researchers to measure the effects of luck; the players didn't know this was happening. There were 3 levels of luck, and each table had 2 players of each level: 1 expert and 1 average. Like this:

So what happened? Here's the key finding: the graph is for Fixed Limit but No Limit was much the same -

Luck, rather than skill, was key in determining final balance, with experts taking no more, on average, than novices. Experts did play differently, on various measures, and seemed better able to cope with bad luck, losing less; but they also won less when given good cards.

The authors conclude:

It can be concluded that chance clearly dominates skill; thus, poker should be classified as gambling

But how expert were these 'experts'? Players were defined as 'experts' if they scored above the median on a questionnaire which asked things like, "How often did you play poker on average per month within the past year?" and "How successful do you regard yourself in terms of poker?" That's obviously a pretty weak measure of expertise. It's entirely self-report, and measures subjective enthusiasm and confidence, rather than skill.

On the other hand though... if you're reading this and thinking "That's BS - but I really am an expert, I really am good at poker" - then you're the kind of person who'd have scored highly on that questionnaire.

Previous work on this question has given mixed results; Dedonno and Detterman argued that "Poker Is A Skill" and found that teaching students some basic strategies made them perform better. Fiedler and Wilcke, however, analyzed a large database of online poker games and found that, while playing about 1000 hands of poker did seem to lead to the development of skill, the majority of online players had much less experience than that, so were at the mercy of chance.

Maybe the 'experts' in this study had played less than 1000 hands?

Meyer G, von Meduna M, Brosowski T, and Hayer T (2012). Is Poker a Game of Skill or Chance? A Quasi-Experimental Study J Gambling Studies DOI: 10.1007/s10899-012-9327-8

Where Have All The Cults Gone?

Why have there been no new religious movements founded in the West for the past 20 years?

That's how it seems, anyway. I've been trying to think of any notable cults, sects or religions that have sprung up in the past 20 years, and I can't think of any.

Contrast this to the period from say 1945 to 1990. New groups were springing up all over the place. Scientology; the Hare Krishnas; Transcendental Meditation; the Moonies; Jesus Freaks; the Manson Family; Heaven's Gate; Jonestown; the Kaballah Centre; the Nation of Islam; the New Age; Neopaganism, Wicca...

These are all household names. But they all date to, at latest, about 1990. Why haven't there been any more since? The Waco siege was in 1993, but the Branch Davidian group was much older. Was Waco the end of an era? It does seem that way...

If so, what happened? I find this really interesting.

First off though, am I right? Maybe there's a boring explanation. Is it just that religious groups take time to become well known, so today's cults are out there, just below the radar? Seems unlikely. Many of the groups I mentioned above were famous within a decade of being founded. Even if this were true, you'd expect us to have a steady stream of newly famous groups, but where are they?

Of course, I may just be ignorant. If you think I'm overlooking some newer groups do let me know.

To be clear, I'm thinking of Western Europe and the USA here; I don't know about the rest of the world.

But if I'm right, what does it mean? What happened in the early 1990s? Here's a few ideas I had; I'm not sure I believe any of them, but they seem plausible -

• The rise of the Internet created new substitutes for religion - such as? Otherkin? World of Warcraft? Blogger.com?
• Secularization means less religion in general, and that includes less new religion
• What we have now is normal, it was the previous few decades that were abnormally rich in new religions and that's what needs to be explained. The 1960s gave us rock and roll, drugs, hippies, feminism, Civil Rights, etc. Have things generally been quieting down since then?
• The Internet / the 24 hour news cycle / Rupert Murdoch etc. has led to increasing homogenization of opinion - towards one pole in Europe, two poles red/blue states in USA... so there's less room for outliers.
• Cults have always been a social club for lonely people. But now we have OKCupid.
• The rise of psychiatry, psychiatric medication, and the increasing readiness to diagnose of mental illness means potential cult leaders and followers end up on Prozac, not
• Religious groups have declined, because all social groups, clubs, parties have declined - the Bowling Alone theory
• It's the decline of Western culture - we have lost the capacity to dream, to invent, to believe.
  
• It's the golden age of western culture - we have so much entertainment, culture, freedoms etc. compared to the past, so less motivation to drop out and create your own culture.

I really don't know what to think, so please do leave a comment. However, please avoid comedy along the lines of "We have cults now - like global warming!!!"...

A Bloody Mess: Pharma, Legal Threats, and Fraud

Over at ScienceInsider, we read that a German pharma company, Fresenius Kabi, threatened a scientist with legal action over a paper published in the New England Journal of Medicine.

The paper asked, in effect: what's the best way to boost blood volume after bleeding? The old-fashioned - and cheap - approach is to give water with various salts, called Ringer's solution. However, it has been proposed that it might be more effective to add a form of starch to the mix, specifically hydroxyethyl starch (HES).

In essence, just as you can use starch to thicken a soup, HES helps to bulk out the blood, increasing the volume, to better compensate for fluid loss. However, HES carries the risk of side effects, including severe kidney damage.

Do the benefits outweigh the risks? That was the question asked by a team of researchers led by Danish Dr Anders Perner. In a double blind, randomized controlled trial, Perner and colleagues compared a particular kind of HES (6% HES 130/0.42) to Ringer's solution, in patients with severe sepsis (blood poisoning) treated in intensive care.

The results showed that HES was actively harmful. It raised the risk of death in these severely ill patients. 51% died, compared to 43% in the control group:

Phew! Glad we know that. If you ever end up in intensive care with sepsis, this paper could well have improved your chances of survival.

Here's where the legal threats came in. When Perner et al published their work, they described it as a trial of 6% HES 130/0.4. It was in fact a trial of 6% HES 130/0.42. Spot the difference? Fresenius Kabi did, and they weren't happy, because they sell the 130/0.4 product. The trial was, incorrectly, billed as being about their product. It was in fact about a very similar product.

And they really are very similar. The 0.4/0.42 refers to the average hydroxylethyl ratio of the starch. But this is only an average - it varies from molecule to molecule. At ScienceInsider, Perner points out that the ratio varies between 0.40 to 0.44 in the "0.42" brand, and 0.38 to 0.45 in Fresenius Kabi's "0.4".

That's a lot of overlap... 100% overlap actually. Still, a mistake is a mistake, so Perner was right to correct it, but why couldn't they just have asked nicely?

Well... maybe because it's not the first controversy involving Fresenius Kabi and their starchy solutions. In fact, they're linked to one of the biggest scientific scandals in recent years: the case of Dr Joachim Boldt. Boldt was one of the leading researchers in his field, until last year when it was revealed that much of his work was fraudulent, unethical, or both. He's since been made to retract over 90 of his papers - which at one time made him the most-retracted scientist ever.

Now Boldt's main research interest was... hydroxyethyl starch. Much of his work - including many of the retracted papers - seemed to show that HES was both safe and effective, and he received funding from Fresenius Kabi.


So, the fall of Boldt must have deal FresKab a bit of a blow. They developed HES, back in the 1970s, and now the star cheerleader for their invention has been revealed as one of the biggest medical fraud in history. It's not hard to see why they might be feeling especially sensitive right now.

Sure, Boldt received funding from other companies too, and FresKab funded plenty of other researchers too. There's no reason to believe that they were aware of Boldt's misconduct, or that they encouraged it. But indirectly they almost certainly did benefit from it.

Anyway, following the legal threats, the NEJM has now corrected the Perner study. It was not a study of Fresenius Kabi's product. Rather, it was a study of a very similar product, and it showed that this very similar product kills people. So spread the word!

Perner A, & et al (2012). Hydroxyethyl starch 130/0.42 versus Ringer's acetate in severe sepsis. The New England journal of medicine, 367 (2), 124-34 PMID: 22738085

How To Lose Twitter Followers

Inspired by David Allen Green's How to lose followers on Twitter, I thought I'd share some tips on what to avoid doing if you want to be big on Twitter.

I don't think there's any simple formula for gaining followers. You just need to write "good" Tweets, where "good" is impossible to define and depends on what kind of thing you write about. However, there are some simple things that are pretty sure to lose you followers.

• Send a Tweet. Every time you Tweet, expect to lose followers. People will unfollow you when they see your Tweets and decide they don't want to hear more, and the more you post, the more likely they are to feel it's too much. Dense "bursts" of Tweets, in particular, may make people decide that you're taking up too much space in their time line. Tweeting is the only way to gain followers, but unless a Tweet actively gains followers, it will lose them.
• Treat Twitter as a social network. It's not. Or rather, it can be, and that's fine if you want to use it that way. But if you care about your follower count, then you're probably not thinking of it as one. Twitter is a microblogging platform, so treat your Tweets like blog posts aimed at your audience, rather than personal "chat" messages. Chat Tweets rarely gain followers... and that means they lose them (see above). It's not an absolute rule, and if you never chat, it will cut you off from important discussions. But chat should not be your default mode.
• Spam. There are various services that make cookie-cutter Tweets on your behalf. Usually they're a round up of your recent Tweets, or a follower count. In general, avoid these. Your followers want to hear from you, not from a robot, and they want to hear your thoughts, not your Twitter stats. They can be useful, but think very careful before using these.
• Be Bilingual. If you speak more than one language, that's awesome. It means you can communicate with more people. But don't try and mix languages on the same account. If half your Tweets are English and half are French, then half your Tweets are essentially just meaningless clutter, for any given follower. Make two accounts, one per language, and you'll get more followers overall.

Questionnaire Extremism and National Character

"Personality differences" between people from different countries may just be a reflection of cultural differences in the use of 'extreme' language to describe people.

That's according to a very important paper just out from an international team led by Estonia's René Mõttus.

There's a write up of the study here. In a nutshell, they took 3,000 people from 22 places and asked them to rate the personality of 30 fictional people based on brief descriptions (which were the same, but translated into the local language). Ratings were on a 1 to 5 scale.

It turned out that some populations handed out more of the extreme 1 or 5 responses. Hong Kong, South Korea and Germany tended to give middle of the road 2, 3 and 4 ratings, while Poland, Burkina Faso and people from Changchun in China were much more fond of 1s and 5s.

The characters they were rating were the same in all cases, remember.

Crucially, when the participants rated themselves on the same personality traits, they tended to follow the same pattern. Koreans rated themselves to have more moderate personality traits, compared to Burkinabés who described themselves in stronger tones.

Whether this is a cultural difference or a linguistic one is perhaps debatable; it might be a sign that it is not easy to translate English-language personality words into certain languages without changing how 'strong' they sound. However, either way, it's a serious problem for psychologists interested in cross-cultural studies.

I've long suspected that something like this might lie behind the very large differences in reported rates of mental illness across countries. Studies have found that about 3 times as many people in the USA report symptoms of mental illness compared to people in Spain, yet the suicide rate is almost the same, which is odd because mental illness is strongly associated with suicide.

One explanation would be that some cultures are more likely to report 'higher than normal' levels of distress, anxiety - a bit like how some make more extreme judgements of personality.

So it would be very interesting to check this by comparing the results of this paper to the international mental illness studies. Unfortunately, the countries sampled don't overlap enough to do this yet (as far as I can see).

Mõttus R, et al (2012). The Effect of Response Style on Self-Reported Conscientiousness Across 20 Countries. Personality and Social Psychology Bulletin PMID: 22745332

On Twitter, It's Beer Before Liquor

People tweet about beer in the evenings, especially on Fridays, according to a not-very-surprising-but-still-fun little report in the journal Epidemiology: Using Twitter to Measure Behavior Patterns

The study used timeu.se, a free searchable database of millions of Tweets. The site grew out of an excellent bit of research you might remember from last year that examined how average mood varies over the course of the day and year.

People tweet about and presumably drink beer (and wine) most in the evenings, especially on Fridays and Saturdays. Smoking-related tweets however were mostly flat, although there did seem to be a small peak in the mornings.

So I ran a few searches of my own, and I noticed that different drinks peak at different times. "Beer" is most popular in the early evening, closely followed by "Wine", but "Vodka" doesn't max out until midnight.

Looks like people are not following the old "beer before liquor, never sicker" rule.

Also, while wine gets the most tweets during the week, beer and vodka really take off at the weekend.

 Cunningham A. John (2012). Using Twitter to Measure Behavior Patterns Epidemiology DOI: 10.1097/EDE.0b013e3182625e5d

Brains In Motion Are Bad For Neuroscience

A new paper in Human Brain Mapping reports on: Functional magnetic resonance imaging movers and shakers: Does subject-movement cause sampling bias?

Head movement is a well known problem that can badly impact the quality of neuroimaging data, introducing spurious signals and obscuring real ones. It's an issue for all brain scanning research but according to Wylie and colleagues, authors of this paper, it's especially serious for studies comparing disease patients to healthy controls.

The authors got 34 people with multiple sclerosis (MS) to perform some simple cognitive tasks during fMRI scanning. They found that the harder the task was, the more the patients moved around during the scan; and in those with more severe MS, the correlation between difficulty and motion was even stronger. In healthy people, harder tasks only caused slightly more motion.

And the more people moved, the less brain activity was recorded, probably because movement degraded the data quality.

fMRI data associated with severe head movement is frequently discarded. In discarding these data, it is often assumed that head-movement is a source of random error, and that data can be discarded from subjects with severe movement without biasing the sample. We tested this assumption by examining whether head movement was related to task difficulty and cognitive status among persons with multiple sclerosis (MS).

[In the MS patients] there was a linear increase in movement as task difficulty increased that was larger among subjects with lower cognitive ability. Analyses of the signal-to-noise ratio (SNR) confirmed that increases in movement degraded data quality. Similar, though far smaller, effects were found in healthy control subjects. Therefore, discarding data with severe movement artifact may bias multiple sclerosis samples such that only those with less-severe cognitive impairment are included in the analyses. However, even if such data are not discarded outright, subjects who move more will contribute less to the group-level results because of degraded SNR.

Oh dear. fMRI researchers use two main ways to deal with motion - correction, and rejection. Either you try to take account of movement and analyze the data, or you just throw out the results from people who move a lot. Most people use a combined approach, chucking out the really heavy movers and then using correction on the rest.

This paper however shows that both techniques have problems. Despite motion correction, data from heavy movers has a lower signal to noise ratio, so if you include them, they will "dilute" your sample. However, if you chuck them, that'll also introduce bias, because heavy movement is not random - people with more severe MS move more, so by excluding heavy movers, you'll be excluding severe cases.

Informally, every neuroimaging researcher knows that some people move more than others. Learning to spot likely "movers" and avoid wasting money on scanning them is a fine art. In my experience just about every "patient" population move, on average, more than healthy controls, and children and the elderly move more than young adults.

I'm not sure there's an ideal solution but perhaps the best approach is to run all analyses (at least) twice, once including everyone, regardless of movement, and then again, with strict movement exclusion criteria. Results consistent across both analyses are probably solid.

Wylie GR, Genova H, Deluca J, Chiaravalloti N, and Sumowski JF (2012). Functional magnetic resonance imaging movers and shakers: Does subject-movement cause sampling bias? Human brain mapping PMID: 22847906

DSM-5 R.I.P?

Yesterday, the proposed new DSM-5 revision of the American Psychiatric Associations "Bible of Psychiatry" came under yet more criticism.

Aaron T. Beck, the father of currently-mega-popular cognitive behavioural therapy, started it off with an attack on the upcoming changes to one diagnosis, Generalized Anxiety Disorder; but many of the points also apply to the other DSM-5 proposals:

The lack of specific features, which is the primary issue for GAD, will not be addressed in DSM-5. The hallmark of the condition will remain pathological worry, although it also characterizes other disorders. Likewise, the proposed behavioral diagnostic criteria lack specificity for GAD, and it is not clear how these will be assessed. The proposed changes will lower the diagnostic threshold for GAD in DSM-5... many currently subthreshold cases will qualify for this diagnosis. The likely inclusion of many such "false-positives" will result in an artificial increase in the prevalence of GAD and will have further negative consequences.

Then from across the Atlantic, and also across the psychotherapy-vs-medication divide, came another piece of criticism. The authors are all associated with the European Medicines Agency (EMA, Europe's equivalent of the FDA), or with national drug regulators. Although they're writing in a personal capacity, this is still big news if you ask me.

These authors start out by saying that the EMA is broadly in favour of DSM reform, but they then attack one of the key DSM-5 innovations - the move towards 'dimensional measures' of symptoms in addition to diagnoses:

One of our main concerns is related to potential future [drug] indications based on an effect on a dimension that is independent of diagnostic categories (although we acknowledge that non-specific claims are common in other areas, such as analgesics for pain). As an example, cognitive impairments are common in psychiatric disorders, but they do not have a unique clinical pattern or a unitary cause.

We therefore believe that, at present, such a cross-cutting approach may increase heterogeneity in patient populations and make the assessment of the benefit–risk balance more difficult. Similarly, the use of dimensions as key secondary end points in many different diagnostic categories may lead to pseudospecific indications and polypharmacy. As a general rule, a therapeutic indication should be a well-recognized clinical entity that is clearly distinguishable from other conditions...

They also echo Beck in warning of over-diagnosis and over-medicalization:

Current proposals to reclassify some conditions that were subthreshold or prodromal as distinct syndromes or disorders could have implications for clinical trials. The inclusion of milder or very early cases of psychiatric disorders may lead to an increase in the number of non-disordered (false-positive) patients in clinical trials, and to an increase in the placebo effect, as less severe cases are more likely to respond to placebo. It may therefore be difficult to show a statistically significant difference [of drug over placebo]...

This raises another highly controversial issue: the risk of medicalization of the normal population. In this respect, a strong concern comes from the proposal to remove bereavement exclusion from the criteria for major depressive disorder, implying that all individuals with ‘normal grief’ might be considered as patients in the future.

Regular readers will remember that I've covered both overdiagnosis screwing up clinical trials, and the bereavement debate.

Two and a half years ago, shortly after the first draft of the DSM-5 was made public, I predicted that the eventual release of DSM-5 would be a non-event because, by then, it would have been widely debated and criticized, destroying the illusion of expert consensus that any such document must have in order to succeed.

I think events have borne this out. An awful lot of professionals, patients, and their relatives, will reject the changes in favour of sticking with the DSM-IV or other criteria. Without swift and general acceptance, a document like the DSM is just paper. It seems increasingly likely that the DSM-5 is going to be dead on arrival.

Starcevic V, Portman ME, & Beck AT (2012). Generalized anxiety disorder: between neglect and an epidemic. The Journal of nervous and mental disease, 200 (8), 664-7 PMID: 22850300

Florence Butlen-Ducuing et al (2012). DSM‑5 and clinical trials in psychiatry: challenges to come? Nature Reviews: Drug Discovery DOI: 10.1038/nrd3811

Love Truth? Wait.

Britain may be hosting the Olympics, but that hasn't stopped us indulging in our own national sport of complaining. Many of the complaints in the past 24 hours or so have been about this chap:

Rileyy_69 attacked a celebrity on Twitter, who called him out on it, rileyy_69 attacked him more, thousands of fans of said celebrity attacked him, he attacked some of them back, then he apologized, but then attacked again, and eventually someone reported him to the police, and he was arrested on Tuesday morning for malicious communications or something.

All very exciting, but so what?

Should we pity this guy, or did it he bring it on himself? Were the thousands who attacked him jumping on the bandwagon, or justifiably outraged? Should he have been arrested, and if not, why? Because the law in question ought to be repealed, or because it's a fine law but was wrongly applied in this case?

Good questions. We don't know enough yet to answer them. We don't know this person, his life story, his mental health situation, etc. Some details have now started to emerge, but generally the early, fragmentary reports in cases like this only add to the confusion.

It's too early to tell. I don't think anyone can dispute this. Unless you i) know Rileyy69 in real life and ii) are an expert in the relevant areas of law and iii) have read all his Tweets, not just the ones that made it into the newspapers, you are probably not in a position to judge.

It's too early to say, but that's never stopped anyone.

Newspapers and blogs are full of definitive, final judgements on these questions. Both those broadly in favor of the arrest of Rileyy_69, and those opposed, are equally premature. If there is a difference, it's that the latter group also include hypocrites, who swiftly took to Twitter to criticize the knee jerk mob mentality of the Twitterati.

One who really cared about Rileyy_69, the law, the media, or whatever else they claimed to, would above all want to establish the facts before commenting. The truth will out; we can but wait, or try to help it along. But we should not try to outrun it.

The truth is slow.

And that's fine. There's rarely, and certainly not in this case, a need to form your opinions within minutes and to nail your theses to the door of the cathedral within a day of the event. Just wait! You'll be in good company; few of the great minds of history measured time in hours.

"Ah", you might say, "but those who attacked Rileyy_69 on Twitter were, themselves, doing what you're criticizing!". They were, actually, but that's what Twitter is for. Tweets are about speed and in its place, that's fine. The human brain responds to stimuli within about 100 milliseconds; you give people the chance to type that response, and they will. To criticize that is to criticize human nature.

No, the problem is not those who use an avowedly instant communication service as intended. It's those who try to export that mode of thought into the ancient and higher medium of prose longer than 140 characters.

For everything there is a time, a time to Tweet and a time to think. Just don't mix them up.