Month: April 2012

BBC Future column: earworms

From a couple of weeks ago, my column from BBC Future, about everyday brain quirks (as I’ve mentioned previously). Thanks to Maria Panagiotidi for help with this one.

“Earworms”, some people call them. Songs that get stuck in your head and go round and round, sometimes for days, sometimes for months. For no apparent reason you cannot help yourself from humming or singing a tune by Lady Gaga or Coldplay, or horror upon horrors, the latest American Idol reject.

To a psychologist – or at least to this psychologist – the most interesting thing about earworms is that they show a part of our mind that is clearly outside of our control. Earworms arrive without permission and refuse to leave when we tell them to. They are parasites, living in a part of our minds that rehearses sounds.

We all get these musical memories, and people appear to have different ones, according to a team at Goldsmiths University in London, who collected a database of over 5,000 earworms. True, the songs that we get stuck with tend to be simple and repetitive, but it seems we are not all singing the same number one song at the same time.

Lost in music

Neurologist Oliver Sacks wrote in his book Musicophilia that earworms are a clear sign of “the overwhelming, and at times, helpless, sensitivity of our brains to music”. Music is defined by repetition, just like earworms, and this might make earworms so hard to shake – they are musical memories that loop, say a particular verse or a hook, forever repeating rather than running to completion. Some people report that singing an earworm to the end can help get rid of it (others report in frustration that this does not work at all).

As well as containing repetition, music is also unusual among the things we regularly encounter for being so similar each time we hear it. Fences are visually repetitive, for example, but each time you see the same fence you will look at it from a different angle, or in different light. Put a song on your stereo and the sound comes out virtually identical each time. Remembering is powerfully affected by repetition, so maybe the similarity of music engraves deep grooves in our mind. Grooves in which earworms can thrive.

Another fact about earworms is that they often seem to have something interesting or usual about them. Although they will often be simple and repetitive bits of music, tunes that become earworms have a little twist or peculiarity, something that makes them “catchy”, and perhaps this is a clue as to why they can take hold in our memory system. If there was nothing unique about them they would be swamped by all the other memories that sound similar too.

Slave to the rhythm

If you have got a particularly persistent earworm you can suffer an attack of it merely by someone mentioning the tune, without having to hear it. This proves that earworms are a phenomenon of long-term memory, rather than merely being a temporary “after-image” in sound.

But this is not the whole story. Human memory researchers have identified so called “slave systems” in our short-term memory, components of the mind which capture sights and sounds, keeping them alive for a short time while we focus on them.

One slave system is the “mind’s eye”, capturing visual information, another is the “inner ear”, the part we use for remembering phone numbers, for instance. It is this second part that seems to get infected with earworms. Rather than rehearse our plans for the day, idle thoughts, or lists of things to remember, the inner ear gets stuck on a few short bars of music or a couple of phrases from a song. A part of us that we normally do not have to think about, that should just do what we ask, has been turned against us, tormenting us with a jukebox request that we never asked for.

That our minds are not a unity is one of the basic insights of modern psychology – it is the story Dr Freud was telling, and, although it differs on many of the details, modern cognitive neuroscience says a similar thing. The sense of our selves is not the only thing going on in our minds, psychology says. The mind is an inner world which we do not have complete knowledge of, or have control over.

Mind games

Fortunately psychology can provide some vital intelligence on how to deal with an unruly mind. Consider the famous “don’t think of a white bear” problem, which as it implies involves trying not to think about white bears. Try this yourself, or you can set it as a challenge for a loved one you would like to torment. This problem is a paradox: by trying not to think of a thing you constantly have to be checking if you are still thinking of it – re-invoking precisely the thing you are trying not to think of.

The general solution for the white bear problem is to do something else, to avoid both thinking of the white bear and not thinking of the white bear. For earworms, the solution may be the same. Our inner ear, a vital part of our cognitive machinery for remembering and rehearsing sounds, has become infected with an earworm. This is a part of ourselves which is not under our control, so just sending in instructions to “shut up” is unlikely to be of much help (and has been shown to make it worse). Much better is to employ the inner ear in another task, preferably something incompatible with rehearsing the earworm.

If earworms survive because of their peculiarity, the hook that makes them catch, then my prediction for ridding yourself of an earworm is to sing songs that are similar. If your mind is poisoned by Brittany Spears’ Toxic, for instance, then try singing Kylie Minogue’s appropriately titled Can’t Get You Out Of My Head. By my theory this will erode the uniqueness of the memory habitat that lets the earworm survive. Let me know if it works!

Link: My columns at BBC Future
Link: UK readers – you’ll have to try it via here

Is the brain the centre of your universe?

The Observer has a fantastic debate between neuroscientists David Eagleman and Raymond Tallis about how much brain science tells us about free will and the unconscious.

It’s a wonderful pairing as Eagleman is a broad-thinking wonderboy of neuroscience while Tallis is a veteran street-fighter of brain debates.

The main point of contention revlves around whether we can understand the brain as the source of human nature or whether we have to look beyond the individual to make sense of our experience and behaviour.

Eagleman: It is clear at this point that we are irrevocably tied to the 3lb of strange computational material found within our skulls. The brain is utterly alien to us, and yet our personalities, hopes, fears and aspirations all depend on the integrity of this biological tissue. How do we know this? Because when the brain changes, we change…

Tallis: Yes, of course, everything about us, from the simplest sensation to the most elaborately constructed sense of self, requires a brain in some kind of working order. Remove your brain and bang goes your IQ. It does not follow that our brains are pretty well the whole story of us, nor that the best way to understand ourselves is to stare at “the neural substrate of which we are composed”.

This is because we are not stand-alone brains. We are part of community of minds, a human world, that is remote in many respects from what can be observed in brains. Even if that community ultimately originated from brains, this was the work of trillions of brains over hundreds of thousands of years: individual, present-day brains are merely the entrance ticket to the drama of social life, not the drama itself.

As an accompaniment to the piece, I also wrote a ‘brief guide to neuroscience’ that you can also read online.
 

Link to debate ‘The brain… it makes you think. Doesn’t it?’
Link to ‘A brief guide to neuroscience’.

The delightful science of laughter

Neuroscientist Sophie Scott gave a fantastic talk on the science of laughter for a recent TEDx event that you can now watch online.

Talks on the science of humour are famously humourless (usually made all the more dire by the desperate inclusion of some not very funny ‘funny cartoons’) but this discussion of laughter is appropriately delightful.

Scott describes a study her team carried out on the cross cultural recognition of non-verbal vocal sounds (like whoops of triumph) to find that only laughter was universal.

The whole talk is fully of such fascinating snippets, tackling both the social psychology and neuroscience of laughing. Well worth ten minutes of your time.
 

Link to ace talk on the science of laughter.

Mind Changers back for another series

BBC Radio 4’s brilliant psychology series Mind Changers has made a comeback and has a new season looking at some of the biggest ideas in cognitive science.

It has kicked off with programmes on South African psychologist Joseph Wolpe and the treatment of anxiety as well as an edition on Julian Rotter and the idea of locus of control or the extent to which we believe that we can control events that affect us.

As always, the series is fantastic, looking not only at the ideas but also the people behind these key theories in psychology.

Wait, you say, one of the BBC’s finest series on psychology, back for another series and available online, surely this too good to be true?

As it turns out, which is almost always the case with the Beeb’s digital offerings, it is too good to be true. The flaw this time is that there are no podcasts – only online streaming.

So in light of the BBC’s inability to keep up with the digital world, I’ve included a picture of Julian Rotter smoking a pipe. Especially pertinent as he looks like he’s thinking “torrent servers, my friends, torrent servers”.
 

Link to excellent Mind Changers series.

Snakes on a brain

The latest Journal of Neuroscience features a study on the neuroscience behind Akiyoshi Kitaoka’s famouse Rotating Snakes illusion and to celebrate they’re made a ‘Rotating Brain’ illusion for the front cover.

This type of illusion, often called a peripheral drift illusion, was thought to occur due to slow drifting eye movements but this new study suggests that it is more likely to be explained by rapid but tiny eye movements called saccades.

Brain-shaped version of Akiyoshi Kitaoka’s “Rotating Snakes” illusion. In its usual presentation, the image consists of concentric circles of stepwise luminance gradients with curved edges, which produces a strong illusion of rotation in most observers. New evidence suggests this illusion is produced by transient oculomotor events such as microsaccades, saccades, and blinks, rather than continuous drift.

Despite the fantastic cover I expect the journal to outdo itself next time and have both an article explaining the neuroscience Brocken spectre as well as an image you can hide up a mountanside to create 20 metre tall ghost-like figures.
 

Link to study (via

Don’t tase my lobe

A case report in Forensic Science International describes a man who had a taser dart penetate his skull and damage his frontal lobes after getting in a drunken confrontation with police.

Curiously, the man was unaware he had a taser dart in his brain and only went to hospital after he got home and noticed the dart sticking out of his head.

A 27 old man was immobilized by the police while he struggled with a police officer during an identification check and attempted an escape. He had a high level of alcohol at the time of the arrest. A X26 Taser was used to incapacitate and subdue the victim.

No immediate medical examination was subsequently performed in the patient after the wires were propelled and he was allowed to return home. However, because he complained of a headache, he decided to go to the nearest hospital a few hours later.

Upon presentation at the Emergency Department the patient was conscious. The examination revealed a harpoon-like barbed electrode dart implanted in the right frontal part of the skull and a right peri-orbital bruise…

The brain CT scan revealed an encephalic injury in the right area of the frontal lobe. In fact, the probe was implanted in the frontal area of the skull and then in the right frontal cortex with a penetration depth of a few millimeters.

There’s a moral in this story somewhere but damned if I can find it.
 

Link to Forensic Science International case report.

A new symbol for epilepsy in Chinese

The Chinese character for epilepsy has been changed to avoid the inaccuracies and stigma associated with the previous label which suggested links to madness and, more unusually, animals.

The new name, which looks like this just makes reference to the brain although the story of how the original name got its meaning is quite fascinating in itself.

The following text is from an article in the medical journal Epilepsia which announced the change:

If you’re wondering where the bit about the ‘bizarre movements of goats’ came I suspect it’s from a type of fainting goat that looks like it has seizures and falls over. You can see them ‘in action’ in this YouTube video.

However, the link is mistaken as the goats do not have seizures. The effect is caused by their muscles locking up, independently of their brain, by a condition called myotonia congenita.
 

Link to ‘Announcement of a new Chinese name for epilepsy’ (via @cmaer)

BBC Future column: Personal superstitions

I’m writing a fortnightly column for BBC Future, about everyday brain quirks (as I’ve mentioned previously). My marvellous editor has told me I can repost the columns here, with a three day delay. There’s a bit of a backlog, including Why can smells unlock memories?, Why you’re bad at names and good at faces, and Why we need to sleep?, but you’ll have to visit the site for them. The column from a month ago was on personal superstitions. And without further ado, here it is:

Legendary Dutch footballer Johan Cruyff used to slap his goalkeeper in the stomach before each match. Tennis ace Serena Williams always bounces her ball five times before her first serve. Jennifer Aniston, it is reported, touches the outside of any plane she flies in with her right foot before boarding.

From touching wood for good luck, to walking around ladders to avoid bad luck, we all have little routines or superstitions, which make little sense when you stop to think about them. And they are not always done to bring us luck. I wait until just after the kettle has boiled to pour the water for a cup of tea, rather than pouring just before it boils. I do not know why I feel the need to do this, I am sure it cannot make a difference to the drink.

So, why do I and others repeat these curious habits? Behind the seemingly irrational acts of kettle boiling, ball bouncing or stomach slapping lies something that tells us about what makes animals succeed in their continuing evolutionary struggles.

Repeat behaviour

We refer to something that we do without thinking as being a habit. This is precisely why habits are useful – they do not take up mental effort. Our brains have mechanisms for acquiring new routines, and part of what makes us, and other creatures successful is the ability to create these habits.

Even pigeons can develop superstitious habits, as psychologist B. F. Skinner famously showed in an experiment. Skinner would begin a lecture by placing a pigeon in a cage with an automatic feeder that delivered a food pellet every 15 seconds. At the start of the lecture Skinner would let the audience observe the ordinary, passive behaviour of the pigeon, before covering the box. After fifty minutes he would uncover the box and show that different pigeons developed different behaviours. One bird would be turning counter clockwise three times before looking in the food basket, another would be thrusting its head into the top left corner. In other words, all pigeons struck upon some particular ritual that they would do over and over again.

Skinner’s explanation for this strange behaviour is as straightforward as it is ingenious. Although we know the food is delivered regardless of the pigeon’s behaviour, the pigeon doesn’t know this. So imagine yourself in the position of the pigeon; your brain knows very little about the world of men, or cages, or automatic food dispensers. You strut around your cage for a while, you decide to turn counter clockwise three times, and right at that moment some food appears. What should you do to make that happen again? The obvious answer is that you should repeat what you have just been doing. You repeat that action and – lo! – it works, food arrives.

From this seed, argued Skinner, superstition develops. Superstitions take over behaviour because our brains try and repeat whatever actions precede success, even if we cannot see how they have had their influence. Faced with the choice of figuring out how the world works and calculating the best outcome (which is the sensible rational thing to do), or repeating whatever you did last time before something good happened, we are far more likely to choose the latter. Or to put it another way: “if it ain’t broke, don’t fix it”, regardless of the cause.

Habit forming

University of Cambridge psychologist Tony Dickinson has taken the investigation of habits one step further. Dickinson trains rats to press a lever for food and perform another action (usually pulling a chain) for water. The animals can now decide which reward they would like most. If you give them water before the experiment they press the lever for food, if you give them food beforehand they pull the chain for water.

But something strange happens if the animals keep practising these actions beyond the point at which they have effectively learnt them – they seem to “forget” about the specific effects of each action. After this “overtraining”, you feed the animal food before the experiment and they keep on pressing the lever to produce food, regardless of the fact that they have just been fed. The rat has developed a habit, something it does just because it the opportunity is there, without thinking about the outcome.

Sound like anyone we know? To a psychologist, lots of human rituals look a lot like the automatic behaviours developed by Skinner’s pigeons or Dickinson’s rats. Chunks of behaviour that do not truly have an effect on the world, but which get stuck in our repertoire of actions.

And when the stakes are high – such as with sports – there is even more pressure on our brains to “capture” whatever behaviours might be important for success. Some rituals can help a sportsperson to relax and get “in the zone” as part of a well-established routine before and during a big game. But some of the habits you see put my kettle boiling routine to shame. Tiger Woods always wears red the last day of a golf tournament, because he says it is his “power colour”. In baseball, Wade Boggs claimed he hit better if he ate chicken the night before. Soccer’s Kolo Toure once missed the start of the second half because refused to come out – superstition dictated he had to be the last player to re-emerge from the dressing room, but on that occasion he was stuck there waiting for a stricken teammate to finish treatment.

We cling to these habits because we – or ancient animal parts of our brains – do not want to risk finding out what happens if we change. The rituals survive despite seeming irrational because they are coded in parts of our brains, which are designed by evolution not to think about reasons. They just repeat what seemed to work last time. This explains why having personal rituals is a normal part of being human. It is part of our inheritance as intelligent animals, a strategy that works in the long-term, even though it clearly does not make sense for every individual act.

Link: My columns at BBC Future
Link: UK readers – you’ll have to try it via here

Less thinking biases in a foreign tongue

A fascinating study just published in Psychological Science has found that solving problems in a foreign language reduces cognitive biases.

The Foreign-Language Effect: Thinking in a Foreign Tongue Reduces Decision Biases

Psychological Science, Published online before print, April 18, 2012

Boaz Keysar, Sayuri L. Hayakawa, Sun Gyu An

Would you make the same decisions in a foreign language as you would in your native tongue? It may be intuitive that people would make the same choices regardless of the language they are using, or that the difficulty of using a foreign language would make decisions less systematic.

We discovered, however, that the opposite is true: Using a foreign language reduces decision-making biases. Four experiments show that the framing effect disappears when choices are presented in a foreign tongue. Whereas people were risk averse for gains and risk seeking for losses when choices were presented in their native tongue, they were not influenced by this framing manipulation in a foreign language.

Two additional experiments show that using a foreign language reduces loss aversion, increasing the acceptance of both hypothetical and real bets with positive expected value. We propose that these effects arise because a foreign language provides greater cognitive and emotional distance than a native tongue does.

 

Link to study summary (via @ProfessorFunk)

The lie detector paradox

I’ve got an article in today’s Observer about the unreliability of ‘lie detectors’ but why people still tend to spill the beans when wired up to them.

It turns out that polygraphs have a sort of placebo effect, where people are more truthful because they believe that they work. In fact, studies show that people are more truthful when wired up to a completely bogus ‘lie detector’ look-alike.

Worryingly though, law enforcement is staring to use this effect, which is based entirely on ignorance, to monitor sex offenders and evaluate their risk of carrying out other sexual assaults.

Needless to say, I feel this is foolish. Read the article for the full details.

By the way, this is the first of an every-six-weeks column I’ll be writing for the paper. As my friends will tell you, I rarely manage to say anything interesting that frequently, so wish me luck.
 

Link to Observer article ‘the truth about lie detectors’.

How Ghostwatch haunted psychiatry

In 1992, the BBC broadcast Ghostwatch, one of the most controversial shows in television history and one that has had a curious and unexpected effect on the course of psychiatry.

The programme was introduced as a live report into a haunted house but in reality, it was fiction. This is now a common plot device, but the broadcast happened in 1992, years before even The Blair Witch Project used the documentary format to tell a fictional story and viewers were used to news-like programmes presenting news-like facts.

But despite some subtle nods to its fictional nature, the fact it was broadcast on Halloween and the ridiculous conclusion (the poltergeist eventually escapes from the house, takes control of the BBC and possesses presenter Michael Parkinson), many people believed the ‘documentary’ was real and that the programme was capturing these astounding events as they happened. You can watch it on YouTube and see how it was introduced.

Consequently, lots of people were genuinely frightened by the programme, including many children who were watching with their families. As a result, the BBC was flooded with calls and letters and were forced to start an investigation into the programme.

As the controversy raged on, an article appeared in the British Medical Journal, written by two doctors from Gulson Hospital in Coventry, reporting post-traumatic stress disorder (PTSD) in two children that was apparently caused by watching Ghostwatch.

Case 1

This boy had been frightened by Ghostwatch and had refused to watch the ending. He subsequently expressed fear of ghosts, witches, and the dark, constantly talking about them and seeking reassurance. He suffered panic attacks, refused to go upstairs alone, and slept with the bedroom light on. He had nightmares and daytime flashbacks and banged his head to remove thoughts of ghosts. He became increasingly clingy and was reluctant to go to school or to allow his mother to go out without him.

Although not without scepticism, several other cases were published as replies to these initial reports producing a small case series of PTSD caused by the TV show.

These minor cases drifted into the history of medicine until people started to debate what event should be considered a sufficiently traumatic event in order to diagnose PTSD.

At the moment, the current DSM-IV-TR diagnosis for PTSD says that “the person experienced, witnessed, or was confronted with an event or events that involved actual or threatened death or serious injury, or a threat to the physical integrity of self or others” and that the person’s response involved “intense fear, helplessness, or horror”.

It’s the “confronted with” part that allows people who have seen distressing things on TV and reacted with “intense fear, helplessness, or horror” to be diagnosed with PTSD.

At the time Ghostwatch was broadcast the criteria required that “the person has experienced an event that is outside the range usual human experience and that would be markedly distressing to almost anyone” which could similarly be interpreted to allow TV programmes to cause the disorder.

The new proposed criteria for the DSM-5 wouldn’t allow television-triggered PTSD. In fact it specifically says that exposure to traumatic events “does not apply to exposure through electronic media, television, movies, or pictures, unless this exposure is work related.”

Ghostwatch has played a part in changing how PTSD will be diagnosed. Although a major motivation was the wave of PTSD diagnoses after watching coverage of 9/11 on TV, the fictional ghost investigation is often cited in the medical literature as an example of how the existing criteria can lead to absurd consequences.

Although the programme is more famous for its effect on the history of media, it remains a minor but significant spectre in psychiatry’s past.
 

Link to GhostWatch entry on Wikipedia.

I predict a riot (based on a single study)

A group of black bloc researchers fed up with the lack of interest in replicating psychology studies has set up a strike force called the The Reproducibility Project that will recreate all 2008 studies from three major cognitive science journals.

That sound you can hear. That’s shit hitting the fan.

The Chronicle of Higher Education covers the project that’ll check-out the replicability of well-known studies.

So why not check? Well, for a lot of reasons. It’s time-consuming and doesn’t do much for your career to replicate other researchers’ findings. Journal editors aren’t exactly jazzed about publishing replications. And potentially undermining someone else’s research is not a good way to make friends.

Brian Nosek knows all that and he’s doing it anyway. Nosek, a professor of psychology at the University of Virginia, is one of the coordinators of the project. He’s careful not to make it sound as if he’s attacking his own field. “The project does not aim to single out anybody,” he says. He notes that being unable to replicate a finding is not the same as discovering that the finding is false. It’s not always possible to match research methods precisely, and researchers performing replications can make mistakes, too.

But still. If it turns out that a sizable percentage (a quarter? half?) of the results published in these three top psychology journals can’t be replicated, it’s not going to reflect well on the field or on the researchers whose papers didn’t pass the test. In the long run, coming to grips with the scope of the problem is almost certainly beneficial for everyone. In the short run, it might get ugly.

Unfortunately, psychology and science in general still see a non-replication as a failure (in fact, we even use the term ‘failed replication’).

This is clearly nonsense and checking the original finding is equally as valuable if the new data agree with, or disagree with, the original study.

Sadly, we’ll have to change the attitude of several generations of scientists to reset this rusty conceptual switch.

The Reproducibility Project have just got frustrated with the entrenched attitudes and have manned the barricades. And who cam blame them?
 

Link to Chronicle article on The Reproducibility Project.

An antidote to post-natal venom

Today’s Observer has a remarkably vicious article about post-natal depression in fathers that is quite breathtaking in both its ignorance and its venom:

“One notices more talk of postnatal depression in fathers. I use the word “talk” advisedly, scientific proof still being in short supply. Were hormonal levels tested? Was postpartum bruising measured? How about the emergence of a human head in what – in deference to what might be your leisurely Sunday breakfast – I will refer to as the front-bottom area? In fact, was there anything at all to suggest that the subject had, at any point, given birth, thus making sense of adding the term “postnatal” to depression?”

Firstly, journalist Barbara Ellen clearly doesn’t know the difference between postnatal (after a child has been born) and postpartum (after giving birth). It is equally as possible to describe postnatal depression in fathers as it is to describe men, or indeed, women, having a postnatal breakfast.

The statement about “scientific proof still being in short supply” is just odd considering she then goes on to cite a study of 8,431 fathers published in the Lancet on postnatal depresison.

However, this is by no means the only study, as there are plenty more where that came from.

Ellen is also convinced that postnatal depression is “directly related to the physical act of pregnancy and childbirth”.

It is surely the case that the act of being pregnant and giving birth does increase the risk of postpartum depression owing to hormonal changes, but we also know, for example, that disruption to sleep patterns is also a risk factor – something that could equally affect both partners.

This part, though, is just amazingly and needlessly cruel:

I would have been more concerned that the mothers in question were having to put up with such exhausting narcissists as partners – men incapable of hiding their sulky self-absorption, even while being watched by researchers for a period of, wait for it, three minutes. Even serial killer Ted Bundy managed to look “normal” for longer than that.

Sadly, that’s not the only insult thrown in to the mix and just to top it off, the piece finishes on a logical fallacy / insult combo – enter the false dichotomy applied to human suffering:

It was a long, hard road for womankind, getting postnatal depression recognised as a condition, and also to receive medical attention or even routine sympathy. It seems to me that saying men can also get it is just cheapening this achievement.

Mental health is important for all and we don’t cheapen anyone else’s suffering by recognising the pain of others.
 

Link to nasty opinion piece (via @mjrobbins)

City flow

Slate has a wonderful article on the science of city walking that examines how pedestrians behave when moving through the city and how our behaviour is being captured to model the flow of people through the urban landscape.

The piece is full of subtle observations of city psychology:

Block by block, they emerge: The way people drift toward the shady side of the street on hot days; the way women (in particular) avoid subway grating on the sidewalk; the way walking speeds are slower at midday than before or after work; the way people don’t like to maintain the same walking speed as a stranger next to them; the way tourists walk in inappropriately spread out groups (a phenomenon captured by this satirical call for “tourist lanes”); the way sidewalk planters, parking meters, and other obstacles reduce the “effective width” of sidewalks, which have been under slow and steady spatial assault since the early 20th century…

Since Zupan’s research, a few new behaviors have come on the scene. One behavior pointed out to me by traffic engineer Sam Schwartz is people pausing before they enter the stairs of a subway station to check their mobile device one last time. Who knows what this social hiccup does to the overall efficiency? Recent research by the New York City Department of Transportation has found that when walkers talk on the phone, they walk more slowly, and when they wear headphones, they actually walk faster. As Zupan told me, “There are a lot of really microscopic dynamics—as Yogi Berra said, ‘You can see a lot just by observing.’ ”

It also discusses how these behaviours are now being included in statistical models to help town planning and architecture.

It’s an interesting problem that has a parallel with thermodyanmics. While we need to understand the interaction of single particles it is the macro level and how it excerpts pressure on the system which allows us design better mechanisms.

By the way, the science of pedestrian dynamics is becoming increasingly important and if you want to read more, a recent Economist article comes highly recommended.
 

Link to Slate article ‘Sidewalk Science’.

Hallucinating fairy tales

Two cases of hallucinated fairy tales from the medical literature.

In this case [pdf] from The Bulletin of the Yamaguchi Medical School, a ballerina presents with magical hallucinations during an episode of psychosis:

…she felt as if she had become the heroine of “The Sleeping Beauty” and this feeling started manifesting itself in her daily behaviour.

She began to hear a voice coming from nowhere telling her that she was Cinderella. She had an experience in which upon seeing a pumpkin she ordered it to become a carriage and then saw a vivid image of a carriage like the one pictured in an illustration in the book.

She claimed that while practicing ballet, she did not feel that she was dancing by her own will, but instead felt as if she was a puppet controlled and manipulated by an unknown force.

In this case from Epilepsy and Behavior a 33-year-old woman experiences a magical cat when her visual cortex is stimulated during brain surgery:

At one parieto-occipital electrode, stimulation with a current of 15 mA elicited the hallucination of a colored creature, spontaneously identified as the leading character of the fairy tale the patient was reading aloud at that moment—a cat (Puss in Boots, by Charles Perrault; the text did not include pictures)…

According to her description, the cat emerged from the script she was holding in front of her, and then moved to the right side of her bed, that is, to her lower right visual hemifield. The cat was 10–20 cm high and flat, two-dimensional like a sheet of paper. It then rotated itself 90° so that its feet pointed toward her and its head was toward the right. When she tried to look at it more closely, it quickly moved to the right and behind her back—the faster she turned her head, the quicker…

Reading picture books depicting different characters while being stimulated (e.g., a penguin, a miller), she again hallucinated a cat at her right forearm, similar to the one she had seen before. “It is only a feeling of what I see. For me it looks like Puss in Boots because of the large hat…, for me it is just a…. It is difficult to explain.”

 

pdf of Cinderella case.
Link to locked article of Puss in Boots case.

Works like magic

The New York Times has a short but thought-provoking piece on the benefits of supersition and magical thinking. This part particularly caught my eye:

For instance, in one study led by the psychologist Lysann Damisch of the University of Cologne, subjects were handed a golf ball, and half of them were told that the ball had been lucky so far. Those subjects with a “lucky” ball drained 35 percent more golf putts than those with a “regular” ball.

The results are from a 2010 study that looked at the effect of ‘lucky charms’ and good luck superstitions on performance, finding that they genuinely increase our ability to complete self-directed tasks through increased self-confidence.

It’s a fascinating result in light of the typical skeptical response that ‘lucky charms don’t work’ because in many cases they do. Importantly, however, they have their effect on tasks in which our own skill plays a significant part rather than those where random outcome is the prime factor.

In other words, they’d help you at poker but not at roulette.

And if you want to know more about how we acquire supersitions, Tom’s recent article for BBC Future breaks it down.
 

Link to NYT ‘In Defense of Superstition’.
Link to BBC Future article on supersitions acquisition.
Link to locked study.