Month: October 2007

The beauty of false depth

The image is one of many beautiful street art images from artist and architect Kurt Wenner who uses false perspective to give the images an impression of a 3D structure when viewed from a certain angle.

Wenner uses the same optical manipulation as Julian Beever, whose work we covered previously on Mind Hacks.

It takes advantage of the fact that we use visual features such as relative sizes to infer the depths of objects in the visual field.

When this is manipulated, we can be fooled into thinking that a depth is present in spatial dimensions where it can’t possibly exist – like in this case, where it seems as if the paintings represent ‘holes’ in the floor.

However, because in reality, these are flat images, the effect is lost when viewed from an alternative angle.

There are many more stunning images on Wenner’s website.

Link to Kurt Wenner’s street art portfolio (thanks Ceny!).
Link to previous post on Julian Beever’s optical street art.

Strobing numbers show saccadic vision

This week’s New Scientist has a brief letter which describes an elegant demonstration of visual processing during eye movements.

When you move your eyes (known as a saccade), visual input is suppressed, so less information is processed by the brain during the move.

This can be easily demonstrated, as described in one of the hacks in the Mind Hacks book (pdf).

An earlier article in New Scientist suggested that visual perception shuts down completely during the move, and someone wrote in with an elegant demonstration to show that this isn’t the case.

It is not strictly true that your visual perception mechanism shuts down completely during a rapid eye movement (22 September, p 34). This can easily be confirmed by flicking your eyes across a digital clock running off an alternating-current power supply, whose figures are luminous and flash at 100 or 120 hertz. You may see a line of images of the numbers, spaced out in proportion to the speed of your eye movement.

The same applies to a TV image: flicking your eyes to the right or left produces a succession of lozenge-shaped images, whereas flicking up or down results in a series of images respectively drawn out or squashed. If you flick your eyes down fast enough you can reduce the picture to a single bar, and if you flick your head down at the same time you can even manage to invert the picture, though you have to be very quick. Do not attempt this, however, if anyone is watching you.

Link to NewSci letter ‘Saccade effects’.
pdf of hack to demonstrate visual suppression during saccade.

Hypermemory and amnesia in National Geographic

Neurophilosophy has alerted me to the fact that National Geographic magazine has a fantastic cover feature on memory, forgetting, amnesia and hyper-recall in this month’s issue. It’s both freely available online and is accompanied by an interactive 3D brain map of the key memory structures.

The article discusses some of the extremes of memory that have been reported in the neuropsychology literature and describes an encounter both with EP, a patient with profound amnesia after suffering an HSE infection, and AJ, a woman who seemingly has an almost ‘perfect’ memory for her past.

As well as tackling some of the neuroscience of memory, the piece does an excellent job of communicating the characters and frustrations of the people with these remarkable memories

It also contains some wonderful asides about the place memory has in our society, and how that has changed significantly since the advent of technologies such as disposable writing tools that have allowed us to artificially ‘extend’ our memories.

Before that time, the act of remembering was, in itself, a hugely significant skill and quite literally in some cases, the stuff of legend.

It’s hard for us to imagine what it must have been like to live in a culture before the advent of printed books or before you could carry around a ballpoint pen and paper to jot notes. “In a world of few books, and those mostly in communal libraries, one’s education had to be remembered, for one could never depend on having continuing access to specific material,” writes Mary Carruthers, author of The Book of Memory, a study of the role of memory techniques in medieval culture. “Ancient and medieval people reserved their awe for memory. Their greatest geniuses they describe as people of superior memories.”

Thirteenth-century theologian Thomas Aquinas, for example, was celebrated for composing his Summa Theologica entirely in his head and dictating it from memory with no more than a few notes. The Roman philosopher Seneca the Elder could repeat 2,000 names in the order they’d been given to him. A Roman named Simplicius could recite Virgil by heart‚Äîbackward. A strong memory was seen as the greatest of virtues since it represented the internalization of a universe of external knowledge. Indeed, a common theme in the lives of the saints was that they had extraordinary memories.

After Simonides’ discovery, the art of memory was codified with an extensive set of rules and instructions by the likes of Cicero and Quintilian and in countless medieval memory treatises. Students were taught not only what to remember but also techniques for how to remember it. In fact, there are long traditions of memory training in many cultures. The Jewish Talmud, embedded with mnemonics‚Äîtechniques for preserving memories‚Äîwas passed down orally for centuries. Koranic memorization is still considered a supreme achievement among devout Muslims. Traditional West African griots and South Slavic bards recount colossal epics entirely from memory.

Link to National Geographic article ‘Remember This’.
Link to interactive 3D brain map of the key memory structures.

I ask you a question, I wanna know why

Dr Lolita Shant√© Gooden is New York-based psychologist with a block rockin’ background. Under the stage name Roxanne Shant√© she revolutionised hip-hop at the age of 14 when she recorded a direct reply to a popular hip-hop track which became a hit in its own right.

This was one of the first rounds in an avalanche of subsequent musical responses, dis records, and on-air replies – a phenomenon now known as the Roxanne Wars.

She was famously dissed in Boogie Down Production’s track The Bridge is Over but she always gave as good as she got and, over the next decade, defined herself as one of the strongest female MCs in rap music.

Nevertheless, at the age of 25 she decided to go to college and study psychology. She describes in a video how she was funded by a clause in an early record contract that promised to pay for her education.

The record company obviously didn’t think that the young MC, who was already a teenage mother, would amount to much at school.

However, she used the contract to her advantage, applied herself with enthusiasm to her studies, and eventually earned a PhD in psychology.

She now practices in Queens, New York.

Link to Wikipedia page on Roxanne Shanté.
Link to video of Roxanne Shanté explaining how she got her PhD (via MeFi).
Link to MySpace page with audio of key tracks.

Psychic studies may be influenced by suggestion

The BPS Research Digest has discussed a recent study that analysed recordings of parapsychology experiments and has found that some of the positive findings may be due to experimenters unconsciously prompting the participants as they gave their answers.

The experiments used the Ganzfeld technique where one participant has diffuse white light and auditory noise played to them, effectively blocking the key senses, while another tries to ‘send’ images to them through mental projection.

Afterwards, the ‘receiver’ tells the experimenter what images came to mind and the research team see if it matches what the ‘sender’ was trying to transmit.

Taken as a whole, these sorts of experiments show a weak but positive evidence for extra-sensory perception (ESP), but it’s not clear whether this isn’t just due to a tendency for some negative trials not being reported.

In this new study, psychologist Robin Woofit analysed the tapes of Ganzfeld experiments from the mid-1990s and found that experimenters were more likely to respond decisively to correct responses but give subtle cues (such as saying ‘mm hm’) to give more information when the response wasn’t initially accurate.

This suggests that some of the positive findings may be due to this subtle prompting which is known as the Clever Hans effect, after a horse who was thought to be able to do amazing calculations, until it was later discovered that he was simply clopping his hoof until his trainer responded in a positive way.

However, this also highlights another aspects of parapsychology – they do some of the most thorough experiments in psychology.

This new study was only possible because the researchers keep archived audio recordings of every experimental session, something that almost never happens for other psychology studies.

It could be that other experimental findings in psychology are influenced by the Clever Hans effect, but we’ll never know, because few labs keep such thorough records.

Try asking for the audio recordings of decade-old experimental sessions from other areas of psychology if you’re not convinced.

It sometimes strikes me as ironic that some scientists consider academic parapsychologists to be unscientific when they do often some of the most carefully designed studies in the literature.

The fact that these studies typically find no evidence of ESP doesn’t mean they’re not doing science, and in fact, they’re provided some of the best evidence against airy fairy notions of ‘psychic powers’.

UPDATE: This is an important clarification on the study from Christian, which puts a different spin on it:

The observed interaction effect occurred during the review phase, where the researcher goes through the images the receiver spoke out loud earlier as the the ‘sender’ watched the video clip. This is prior to the receiver’s attempt to choose the correct video clip from a few distractors.

The review generally follows the pattern of the researcher saying ‘you said you saw x’, the receiver say ‘yes’ or ‘no’ or maybe elaborates. It was those times the receiver elaborated, that experimenters appeared to have an influence – if they said ‘okay’ and moved onto the next item, then that was that, but if they went ‘hmm mm’ with an enquiring tone, then the receiver tended to ramble on a bit more and lose confidence in their imagery.

I don’t think it is clear that this would make positive results more likely, and could even make a negative result more likely. Remember too that these were double blind experiments, so it is not a case of the experimenters directing the receivers towards the correct imagery. It is possible though that a sceptical researcher could be more prone to the ‘hmm mm’ noises, and therefore would make their receivers less confident.

Link to BPSRD on parapsychology and suggestion.
Link to abstract of scientific study.

Encephalon 34

The 34th edition of the psychology and neuroscience writing carnival Encephalon has just arrived with the best in the last fortnight’s mind and brain writing.

On this occasion it’s hosted by the Distributed Neuron blog, which is part of an ambitious project to create biologically inspired neural network technology.

A couple of my favourites in this edition of Encephalon include depictions of Alice in Wonderland syndrome in migraine-inspired art and an article that considers claims that differences in executive function are almost entirely inherited.

Needless to say, there’s much more in the complete edition.

Link to Encephalon 34.

Feel good necklace

The scientifically accurate molecular jewellery store Made With Molecules has produced this wonderfully alluring endorphin necklace.

The necklace accurately depicts the structure of human beta-endorphin and is wrought in silver to adorn someone who will undoubtedly make you feel as good as the opioid brain chemical itself.

It is handmade by biochemist turned artisan Dr Raven Hanna, and contains each of the 31 amino acids as separate links in the chain.

You’ll notice it has a price tag to match the quality of the craftsmanship, so is strictly for the most glamorous occasions.

Link to Made With Molecules endorphin necklace.

Musicophilia goes live

NPR public radio has recently broadcast two interviews with Oliver Sacks about the cases in his new book Musicophilia – which tackles the neurology of music.

The first interview is only eight minutes and the second, which you’ll have to scroll down to the bottom of the page for, is a more in-depth half hour discussion.

The book itself appeared on the shelves last week and the book’s website has just gone live which, as well as containing information about the new release, also has a series of videos of Sacks discussing everything from why we sometimes can’t get tunes out of our heads, to music and amnesia.

Link to two NPR interviews with Sacks (scroll down for second).
Link to Musicophilia website with videos.

The Tumour in the Rue Morgue

Poe’s final days are as mysterious as the best of his Gothic tales. He was found in the streets of Baltimore, delirious and disturbed before dying the following week in a state of distress.

Many theories have been suggested as to what caused his confusion and eventual death, from poisoning, to a suicide attempt, to syphilis.

The Observer has an article on a new theory by Matthew Pearl, author of a new book on Poe’s death, suggesting his condition may be explained by brain cancer, owing to a curious finding when his body was exhumed some years later.

But Pearl has now discovered evidence that Poe died of brain cancer, which may explain why he had suffered from hallucinations and delusions. Pearl’s evidence came in the form of several old newspaper stories written about the exhumation of Poe’s body 26 years after his death. Poe’s coffin was being moved to a more prominent spot in the cemetery and the onlookers were amazed to see that his shrunken brain was still visible inside his skull. It was described as being ‘dried and hardened in the skull’ in an 1878 article in the St Louis Republican newspaper, whereas a letter in the Baltimore Gazette claimed that: ‘The cerebral mass… evidenced no sign of disintegration or decay, though, of course, it is somewhat diminished.’

Pearl contacted a friend’s wife who worked as a forensic pathologist. She pointed out that the descriptions could not possibly have been of a brain, as it is one of the first parts of a corpse to rot after death. But she said some forms of brain tumours can calcify after death and leave a hardened mass. One account described the brain as almost rattling around inside Poe’s head. Pearl also looked up pictures of calcified tumours and discovered that some resembled shrunken brains.

It’s an interesting theory, but one that will have to remain speculative – unless Poe’s body is ever exhumed again.

Link to Observer article ‘Fresh clues could solve mystery of Poe’s death’.
Link to Wikipedia page on the death of Poe.

Power of birth order

Time magazine has a great article discussing psychological differences that have been picked up by research looking at birth order effects. Interestingly, while first and last borns seems to have distinct traits, middle children are still a bit of a mystery.

Birth order effects seem to be one of those things that can be reliably found when examining large groups but, because of the large amount of individual variation, strong effects are not reliably present on the level of single families.

Nevertheless, the research has found over the population there are, on average, some interesting psychological differences linked to birth order – particularly between first and last borns.

…personality tests show that while firstborns score especially well on the dimension of temperament known as conscientiousness ‚Äî a sense of general responsibility and follow-through ‚Äî later-borns score higher on what’s known as agreeableness, or the simple ability to get along in the world. “Kids recognize a good low-power strategy,” says Sulloway. “It’s the way any sensible organism sizes up the niches that are available.”

Even more impressive is how early younger siblings develop what’s known as the theory of mind. Very small children have a hard time distinguishing the things they know from the things they assume other people know. A toddler who watches an adult hide a toy will expect that anyone who walks into the room afterward will also know where to find it, reckoning that all knowledge is universal knowledge. It usually takes a child until age 3 to learn that that’s not so. For children who have at least one elder sibling, however, the realization typically comes earlier. “When you’re less powerful, it’s advantageous to be able to anticipate what’s going on in someone else’s mind,” says Sulloway.

We featured some studies previously on Mind Hacks that suggested that first born children have marginally higher IQ scores, although a similar study in Thai medical students found the reverse effect, younger siblings tended to be more intelligent.

This highlights the role of culture in these effects, and the Time article illustrates a similar point with regards to girls. Perhaps fifty years ago when girls were less expected to go to college and have careers, the birth order effect may have been much less clear because of the cultural limitations on female work and education.

Now the cultural expectations have changed, the effect of birth order on psychological development may also be different.

Link to Time article ‘The Power of Birth Order’.

To the bunkers! No really, to the bunkers

In another sign the robot revolution is coming, a robot cannon used by the South African military malfunctioned and tragically killed nine and wounded fourteen after firing uncontrollably.

Mechanised self-targeting machine guns with artificial intelligence systems to distinguish between targets (e.g. humans) and non-targets (e.g. trees) are becomingly increasingly common.

Last year Samsung announced that it had developed a machine gun toting robot sentry that can identify and shoot a target up to two miles away.

The system uses twin optical and infrared sensors to identify targets from 2.5 miles in daylight and around half that distance at night. It has a microphone and speakers so that passwords can be exchanged with human troops.

If the password is not accepted the robot can either sound an alarm or fire at the target using rubber bullets or a swivel-mounted K-3 machine gun.

South Korea’s northern border is the most heavily militarised zone in the world, and the southern government has poured millions of dollars into automated military technology.

…

The Intelligent Surveillance and Guard Robot was jointly developed with a South Korean university, and is designed to replace some of the troops guarding the border with North Korea.

North Korea?!? When World War Three is over, someone is going to get a Darwin Award for that decision.

Where’s Asimov when you need him?

Link to ‘Robot Cannon Kills 9, Wounds 14’ from Wired (via BB).
Link to new story on Samsung robot sentry.
Link to Samsung page with specs of their robot sentry.

Forced normalization

I love the way this completely startling fact is dropped into a sentence about one of the pioneers of German neurology:

The work of Wilhelm Griesinger (1817-1868) (whose father was murdered by the family’s insane piano teacher) marks the birth of neurology in Germany.

The excerpt is from a book I’m reading called Forced Normalization (ISBN 1871816378) by Trimble and Schmitz which is nothing to do with forcing people to be normal, but tackles the fascinating phenomenon where some people become psychotic as soon as their epilepsy is successfully treated (their EEG is ‘normalised’).

The person most associated with this concept is Heinrich Landolt, and the book contains a translation of his key 1958 paper in which he reported a case series of people with epilepsy. It contains this interesting conclusion:

Thus, these cases reveal an unmistakable correlation between the course of the psychotic process and the changes in the EEG, in the the paroxysmal focus which is active before and after the twilight state dissolves during this twilight state, and often so completely that the record is normalized. In other words, and putting it more crudely, there would seem to be epileptics who must have pathological EEG in order to be mentally sane…

Interestingly, this phenomenon may have been the basis of Meduna’s false belief that epilepsy and psychosis don’t occur together, leading him to try inducing seizures as a treatment. This was the birth of an idea that was later developed into electroconvulsive therapy (ECT).

This is certainly not the most common pattern, however, as for the majority of people, epilepsy makes psychosis slightly more likely to occur.

Link to more info on ‘forced normalization’.

2007-10-19 Spike activity

Quick links from the past week in mind and brain news:

Third time lucky? After the third time time, it’s seemingly not luck, because we think it’s a pattern, according to research covered by the BPS Research Digest.

Why has Steven Pinker studied verbs for 20 years? Discover magazine publishes an interview and sets up a great feed for a joke. If only I could think of the punchline. Answers on a postcard…

BBC News on findings that fearful faces are recognised faster that happy faces.

The science of truthiness: gossip triumphs over facts in people’s financial decision making, reports The New York Times.

The Phineas Gage Fan Club examines the psychophysics of audiophiles and the limitations of human hearing.

Blood flow may be part of the brain’s information processing system, suggests a new paper in the Journal of Neurophysiology.

ABC Radio National’s Ockham’s Razor on the influence of the pharmaceutical industry on doctors.

Neurophilosophy finds more of the wonderful neurology of Alice in Wonderland: depictions of Alice in Wonderland Syndrome in migraine art.

Friends not sympathetic about your hangover? Banish those easily dismissable subjective impressions with the first psychometrically valid hangover scale.

Cognitive dissonance, one of the most important findings in social psychology, is discussed by PsyBlog.

The LA Times looks at research which has found that we get happier as we age, contrary to media stereotypes.

Yahoo! News on a study that finds that swearing at work can boost team spirit and morale. Running in corridors found to improve productivity.

Psychiatric assessments via video link are just as accurate as face to face consultations, reports Treatment Online.

Language Log brings some sense to the Neanderthals had ‘speech gene’ story that’s been doing the rounds.

These brains rule

It’s a timeless story. Boy meets girl. Boy annoys girl. Girl goes off on a brain eating rampage before battling her creator and finishing the day at a zombie pool party.

I’m not entirely sure what it’s all about, but then again, I don’t think this rather bizarre music video was designed to have any deep symbolic meaning.

It’s not entirely safe for work, mainly due to lots of swearing and flesh eating, but it’s a magical combination of brains and zombie girls, which is good enough for me.

Chat up line for a zombie: I’m conscious of how attractive you are but I’d like to know how you feel.

Note to self: go to bed, you’re rambling.

UPDATE: From Shannon Lark, director of the music video! Grabbed from the comments…

I am actually the Director of OMG BRAINS and I gotta tell you that it does have a very deep symbolic meaning!

Besides poking fun at the entertainment industry by using commercialized hot zombie chicks (who are supposed to be endless drones performing corpse-like activities), we also make a statement of the weight issue in America and how a parent’s negative comments can even hurt a dead person.

Link to zombie brain rampage music video (thanks Laurie!).

The relationship between money and happiness

Newsweek has a brief article on what research has told us about the link between money and happiness. Essentially, more money makes you happier until you’re comfortable, and then, it really doesn’t do much good.

Interestingly though, a study that looked at how happy a number of similarly earning young people were, found that the happier ones went on the make more money later in life.

If money doesn’t buy happiness, what does? Grandma was right when she told you to value health and friends, not money and stuff. Or as Diener and Seligman put it, once your basic needs are met “differences in well-being are less frequently due to income, and are more frequently due to factors such as social relationships and enjoyment at work.” Other researchers add fulfillment, a sense that life has meaning, belonging to civic and other groups, and living in a democracy that respects individual rights and the rule of law. If a nation wants to increase its population’s sense of well-being, says Veenhoven, it should make “less investment in economic growth and more in policies that promote good governance, liberties, democracy, trust and public safety.”

(Curiously, although money doesn’t buy happiness, happiness can buy money. Young people who describe themselves as happy typically earn higher incomes, years later, than those who said they were unhappy. It seems that a sense of well-being can make you more productive and more likely to show initiative and other traits that lead to a higher income. Contented people are also more likely to marry and stay married, as well as to be healthy, both of which increase happiness.)

It’s not only the case that money doesn’t buy happiness, being materialistic is also associated with worse mental health and overall adjustment.

Link to article ‘Why Money Doesn’t Buy Happiness’.

BBC series has an odd definition of alternative

The BBC have announced a new series which will investigate the scientific basis of three ‘alternative therapies’: reflexology, hypnosis and meditation – except that two of them, hypnosis and meditation, are well-supported scientifically validated treatments.

In fact, systematic reviews have found hypnosis to be an effective treatment for reducing nausea and vomiting during chemotherapy, distress during childbirth, irritable bowel syndrome, and needle pain in children, to name but a few. That’s not counting the numerous studies on the cognitive neuroscience of hypnosis and hypnotisability.

Similarly, mindfulness meditation-based therapies have been researched extensively and found to be useful in a large number of conditions.

In fact, they are one of the best treatments to prevent relapse in people who have already had several depressive episodes in the past.

Both hypnosis and mindfulness-based therapy are used in Britain’s National Health Service and the Royal Society of Medicine has its own dedicated hypnosis section.

Although it’s probably true to say that meditation and hypnosis are also used inappropriately by quacks, so are vitamins, painkillers and exercise, none of which are thought of as ‘alternative’.

The measure of a treatment is not only what it does, but what it’s used for. Antibiotics aren’t an alternative therapy unless you’re trying to use them to cure cancer.

Presumably, the BBC’s next series on alternative music will feature The Rolling Stones and U2 (in contrast, I’m guessing reflexology is the Menswear of medicine).

Link to odd BBC programme announcement.