vaughanbell

Vision shift glasses alter time perception

There’s an intriguing study about to be published in Psychological Science finding that people wearing prism glasses that shift everything to the right overestimate the passage of time, while people wearing left-shift glasses underestimate it.

The researchers, led by psychologist Francesca Frassinetti, asked participants to watch a square appear on-screen for varying time periods, and then reproduce the duration or half the duration with a key press.

Glasses that skewed vision to the left seemed to shrink time, while glasses that skew everything to the right expanded it.

Apart from the interesting perceptual effect, it gives further evidence for the idea that our internals model of space and time are heavily linked, to the point where modifying one has a knock-on effect on the other.

In fact, there is increasing evidence that other abstract concepts are implicitly understood as having a spatial layout. Experiments on the SNARC effect have found that numbers seem to have a ‘location’, with larger numbers being on the right and smaller numbers on the left.

At least, that seems to be the case for native English-speakers, but for Arabic speakers, where text is written right-to-left, the reverse seems to be true.

It would be interesting to whether Arabic speakers show a reverse time alteration effect of if they wear prism glasses. Whatever the answer, it would raise lots of interesting questions about how much language influences our abstract ideas and whether it only applies to certain concepts.

Prism glasses have long been a tool in psychology and there is a mountain of research on how we adjust to living in the world even when everything is shifted through the lens.

Tom recently found a fantastic (1950s?) archive film called ‘Living in a Reversed World: Some Experiments on How We See the Directions of Things’ where several volunteers are asked to wear prism glasses for weeks on end.

Hilarity ensues, at least at first, but as co-ordination skills adapt the volunteers can go about their daily tasks, to the point of being able to ride bicycles, even when their vision has been flipped around.

Link to summary of prism and time perception study.
Link to Living in a Reversed World (via @tomstafford)

Human echolocation and blind mountain biking

Psychologist Lawrence Rosenblum has written an excellent short article about a remarkable group of blind mountain bikers who apparently use echolocation to avoid obstacles by making loud click sounds as they ride.

Rosenblum has studied human echolocation in the lab and has shown that we all have some ability to get an idea of the spatial layout of our environment from sound reflection.

But one of the most interesting bits is where he discusses the fact that while echolocation uses sound, we don’t always process it as a conscious hearing experience. It can seem to just be a ‘sense’ of where objects are.

To get a sense of how echolocation works, try this. Hold your hand up about one foot in front of your face with your palm facing your mouth. Put your front teeth together, open your lips, and make a continuous shhhhhh sound. As you make this sound, slowly bring your hand toward your mouth. You will hear the shhhh sound change. What you‚Äôre hearing is the sound reflecting from your hand colliding with the sound leaving your mouth. This interference turns out to be one of the most important types of sound dimensions we use to echolocate objects at close distances.

But this demonstration is exaggerated. The interference patterns used for echolocation are usually too subtle to be consciously heard. This highlights one of the most amazing aspects of echolocation: It‚Äôs rarely experienced as sound. Try using your shhhh sounds to walk slowly toward a wall with your eyes closed. As you come close to the wall, you‚Äôll experience its presence as more of a feeling than a change in sound. It may feel as if there are air pressure changes on your face, an experience also reported by the blind (echolocation was once called ‚Äúfacial vision‚Äù). Echolocation is truly one of your implicit perceptual skills: It allows you to detect aspects of your environment without even knowing which sensory system you‚Äôre using.

Link to post of echolocation and blind mountain bikers.
pdf of Rosenblum study on human echolocation.
Link to DOI entry for same.

Written off more than they can chew

Good God there’s a lot of scientific research on chewing gum. And I mean a lot. Here’s just a few of the latest bulletins from the front line of chewing gum cognitive science.

Chewing gum does not induce context-dependent memory when flavor is held constant [link]

Effects of chewing gum on mood, learning, memory and performance of an intelligence test [link]

Effects of caffeine in chewing gum on mood and attention [link]

Chewing gum alleviates negative mood and reduces cortisol during acute laboratory psychological stress [link]

Chewing gum and context-dependent memory: the independent roles of chewing gum and mint flavour [link]

Chewing gum and context-dependent memory effects: a re-examination [link]

Chewing gum and cognitive performance: a case of a functional food with function but no food [link]

Role of glucose in chewing gum-related facilitation of cognitive function [link]

Chewing gum can produce context-dependent effects upon memory [link]

Chewing gum differentially affects aspects of attention in healthy subjects [link]

Chewing gum selectively improves aspects of memory in healthy volunteers [link]

Effects of three principal constituents in chewing gum on electroencephalographic activity [link]

Smell and taste of chewing gum affect frequency domain EEG source localizations [link]

And not one on whether chewing gum loses its flavour on the bedpost overnight.

Actually, those are just a sample of the cognitive science studies on chewing gum, and there are many more. If you count all scientific studies with ‘chewing gum’ in the title, you get more than 540 to date.

UPDATE: Grabbed from the comments, a great addition from historian of psychology Chris Green:

There is a long history of “scientific” (read: “industrial”) research into the effects of chewing gum. The Beech-Nut company hired Columbia U. psychologist Harry Hollingworth to do a study of the “psychodynamics” of gum-chewing in the mid-1930s. Philip Wrigley also commissioned research and used the “results” (mainly, that gum-chewing reduces tension and improves concentration) to convince to U.S. Army to include (his) gum in the rations of every American soldier who served in WWII. He also tried to convince a variety of businesses to supply gum to their workers, on the strength of the same basic argument.

Hypnosis and criminal mind control in 1890s France

The 19th century French neurologist Georges Gilles de la Tourette is best known for Tourette’s Syndrome, but a fascinating article in European Neurology traces his interest in the criminal uses of hypnosis.

It is full of surprising facts, like that he was shot in the head by a delusional patient who believed that she had been hypnotised against her will, and that he eventually died in a Swiss asylum after developing psychosis caused by syphilis.

We now know that hypnosis cannot be used to make people do things against their will, but at the time it was widely believed that women could be hypnotised to be easy prey to sexual predators, and even that otherwise innocent people could be hypnotised to be killers against their will. Sort of like a 19th century Manchurian Candidate.

The murder of a public notary by Michel Eyraud and Gabrielle Bompard in 1889, in which Bompard said she was hypnotised to be a murderer, made headlines around the world (you can still read The New York Times coverage online) and also served as a public battle over whether hypnosis could be used for criminal ends.

France was the centre of hypnosis research at the time and many experiments were carried out where hypnotised people were asked to ‘kill’ people with prop weapons to test their compliance. Neurologists Gilles de la Tourette and Jean-Martin Charcot were famous for their work on hypnosis and hysteria and weighed into the heated legal debate.

The patient who shot Gilles de la Tourette was not hypnotised, however, although was delusional and believed that she was. Hypnosis is a common theme of psychosis even today and your average inpatient psychiatric ward may well contain a patient or two who believe they are being ‘controlled’ or ‘mesmerised’ by hypnosis.

In Gilles de la Tourette’s case, the incident is notable not least because he suffered a bullet in the brain, had it yanked out, and was writing to his friend about the experience later in the day.

…he was shot – for real – at his home in Paris by Rose Kamper-Lecoq, a 29-year-old former patient from La Salp√™tri√®re and Sainte-Anne who later claimed that she had been hypnotized from a distance…

Rose asked him for some money, claiming that she was without resources because her hypnotism sessions had altered her will, and shot him when he refused. There were three shots, with only the first one reaching its target. Fortunately for Gilles de la Tourette, it resulted in only a superficial occipital wound, and he was even able to write to Montorgueil about the event the same evening.

The article has a copy of the letter with the description “The writing is uneasy, but Gilles de la Tourette reassures Montorgueil and explains that the bullet has been removed, ending the letter with the comment ‘What a strange story’ (‘Quelle dr√¥le d’histoire’)”.

Anyway, a fascinating article, freely available, and full of fantastic images and illustrations from newspapers of the time.

Link to full-text of article (scroll down).
Link to PubMed entry for same.

AI predicts poker bets to three decimals places

Poker is considered one of the most skillful of betting games, but a new study published in the Journal of Gambling Studies reports on an artificial neural network that predicts gambler’s bets to three decimals places.

The system was built by researcher Victor Chan who created a relatively simply backpropogation neural network to predict future plays.

Backprop networks take a bunch of inputs, feed them through layers of loose mathematical simulations of neurons which then make a guess at an output.

Crucially, the network is initially given a set of training data on which it can modify its ‘guesses’ based on how wrong its initial estimation was. The amount of error is fed back through the network and each ‘neuron’ adjusts the strengths of its connections to other neurons to minimise the error next time round.

Chan used the playing patterns of six online Texas Hold ’em players each of whom played more than 100 games each. He entered just an initial series of games for each player to train the network and then asked it to predict how the following plays would go.

…it was to the author‚Äôs surprise that the neural network for M1 upon training turned out to be able to predict a gambler‚Äôs bet amounts in successive games accurately to more than three decimal places of the dollar on average for each of the six gamblers in our data sample across the board.

More importantly, the neural network for M2 upon training was also able to track the temporal trajectory of a gambler‚Äôs cumulative winnings/losses, i.e., successively predict the gambler‚Äôs cumulative winnings/losses, with a similar accuracy again for each of the six gamblers in our data sample across the board.

…the influence of a gambler‚Äôs skills, strategies, and personality on his/her cumulative winnings/losses is almost totally reflected by the pattern(s) of his/her cumulative winnings/losses in the several immediately preceding games.

In other words, from a sample of initial plays, each gambler’s behaviour was almost completely mathematically predictable in the same way across all six people.

Now, if they could only get a neural network to predict plays in strip poker, I think they’d be onto something.

Link to study.
Link to PubMed entry for same.

2009-07-17 Spike activity

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

NPR has a good piece on the vagaries of analysing functional brain scans.

Philosopher Pete Mandik features Mind Hacks as a ‘Top 10 mind and brain blog’ for blogs.com. Shakira yet to call.

The Independent covers the debate on clozapine – the best antipsychotic available that treats mortality-reducing schizophrenia but which causes potentially fatal white blood cell collapse in ~~10%~~ 1-2% of patients. Choose your poison. Discuss.

Psychiatric-service dogs, especially trained to assist patients with mental illness, are discussed by the Wall Street Journal.

BBC News has an opinion piece by always thought provoking against-the-grain psychiatrist Joanna Moncrieff on why psychotropic medication should be considered separately from mental illnesses. Frontier Psychiatrist has a thoughtful response to the debate.

The side-effects from sugar pills nocebo effect is covered by Brain Blogger

Neuroskeptic has a good complimentary piece on the placebo effect in prescribed medication.

There’s a good piece on ‘How chaos drives the brain’ on New Scientist. I always assume chaos is just a sign of caffeine deficiency.

Neurotopia covers a brain imaging study on a ‘super memoriser‘.

The kazillion dollar war on some drugs is featured in a special issue of Mother Jones magazine.

Schizophrenia Forum has a fantastic discussion from some of the world’s leading schizophrenia researchers on the significance of the recent high profile whole genome studies.

Anthropology, teaching and the great student swindle is discussed in an insightful article on Neuroanthropology.

The Wall Street Journal has a piece on the Blue Brain project. Neglects to mention that it becomes self-aware at 2:14 a.m. Eastern time, August 29th.

Crypto ninja Bruce Schneier discusses the interesting concept of privacy salience and the psychology of online service design.

The Chronicle of Higher Education has a piece on how autism and academia can go hand in hand, while BBC News covers a software company that specifically looks for employees on the autism spectrum.

A cute but gimmicky sleep monitor is covered by The New York Times. It describes it as recording ‘brain waves’ but it looks like it uses near infrared spectroscopy to measure blood flow. See what you’re missing ladies.

Nassir Ghaemi is a well known research psychiatrist who writes an increasingly excellent blog called Mood Swings

New Scientist covers the “first-ever neurobiological study of honesty and cheating“, apparently by a journalist with amnesia for all the other studies.

Ding ding. Round 3. More DSM-V bun fighting on Psychiatric News: “I wish to call attention to the imperiousness, arrogance, and secrecy…”

Neurophilosophy covers researching finding that swearing increases pain tolerance.

Jonah Lehrer reviews ‘You Are Here’, a new book on spatial perception and intelligence for The New York Times.

The excellent Situationist blog has a fantastic article on the legal implications of implicit biases.

Dr Shock discusses a recent thought-provoking article on neuroscience and architecture.

Aimless excursions

Photo by Flickr user Y. Ballester. Click for source NPR has an interesting short article on wandering in dementia. Conditions likes Alzheimer’s disease can cause patients to embark on seemingly aimless walks and sometime epic journeys, but nobody is quite sure why it happens.

We are fascinated by the pilgrim, the lost soul, the sovereign wayfarer. In others. In ourselves. The literature of wandering ‚Äî Homer’s Odysseus, Coleridge’s Ancient Mariner, Steinbeck’s Dust Bowl families, Star Trek’s questing starships, for instance ‚Äî fills shelves and shelves. “One wanders through life as if wandering through a field in the dark of night,” writes Lemony Snicket.

For dementia-driven wanderers, the desire to ramble can be amplified…

Scientists are also not sure why dementia often leads to roaming. But there is this sobering statistic from the Alzheimer’s Association: About 50 percent of people who wander will suffer serious injury or death if they are not found within 24 hours.

For this reason, wandering has been a subject of a fair amount of medical research. Unfortunately, it is still largely a mystery and all we know for certain is that patients who wander tend to be physically fitter but more cognitively impaired.

This had led to a number of innovative ideas to prevent patients getting lost, from electronic tracking by mobile phone to decoy bus stops on hospital grounds.

Link to NPR on wandering in dementia.

Chocolate cravings and the menstrual cycle

I’ve just found a remarkable study on how female chocolate cravings vary throughout the hormone cycle and drop off after menopause. While the cravings are not solely explained by hormone changes, some of the effect does seem to be linked.

Perimenstrual Chocolate Craving: What Happens after Menopause?

Appetite. 2009 Jul 9. [Epub ahead of print]

Hormes JM, Rozin P.

About half of American women crave chocolate, and approximately half of the cravers crave it specifically around the onset of menstruation. This study examines whether the primary cause of this “perimenstrual” craving is a direct effect of hormonal changes around the perimenstrum, or rather if the craving is a general response in some individuals to stress or other notable events. Insofar as there is a direct hormonal effect, one would predict a substantial decrease of 38% in total chocolate craving in women post-menopause, corresponding to the proportion of women pre-menopause who report craving chocolate exclusively perimenstrually. Based on a survey of pre- and postmenopausal alumnae of the same University, we report a significant but small decrease in prevalence of chocolate cravings post-menopause. The decrease is only 13.4% and thereby much smaller than a 38% drop predicted by a purely hormonal explanation, suggesting that female reproductive hormones are not the principal cause of perimenstrual chocolate craving.

Last time I posted something about the menstrual cycle, with reference to the effect on race bias, the post attracted some remarkably acerbic comments.

The comment on racism being a “typical British trait” was pure comedy gold, but one asked the question “Why are hormone fluctuations in men not studied as closely or publicized as widely?”.

I did have a look, but as far as I know, men don’t have hormone cycles. If you know different, do let us know as I’d love to know if there is any good evidence for them.

However, the point was that these studies often focus on stereotypes of female behaviour. So this post is offered as food for thought.

Link to PubMed entry for study.

I’ll be outback: Aussies want intelligent killer robots

The Australian military is seeking a human race Judas to design intelligent and fully autonomous robots that will be able to “neutralise threats” for a prize pot of $1.6 million.

From BBC News:

The government wants to develop an “intelligent and fully autonomous system” capable of carrying out dangerous surveillance missions.

Senior officials in Canberra have said they hope that unarmed robotic vehicles will do some of the army’s “dirty work” in such hazardous theatres.

The ultimate plan is for groups of these sophisticated machines to be sent into battle to help neutralise the enemy.

That’s their ultimate plan you idiot, not ours.

Our ultimate plan is to take off and nuke the entire site from orbit. It’s the only way to be sure.

Link to Aussie military’s International Challenge To Destroy Humanity.
Link to BBC News on the end times.

Is that you, Phineas?

The BPS Research Digest has the surprising news that a photo of Phineas Gage has been discovered. He became one of the most famous case studies in neuroscience when he had a large iron rod blown through his frontal lobes in in 1848.

He survived but his frontal lobe damage meant “Gage was no longer Gage”, at least according to his attending doctor, giving us some of the first clues that damage to specific brain areas could cause changes in personality.

The photo was apparently discovered by two photo collectors who went to great lengths to verify it was indeed Gage.

The photo may well show Gage in his later years as he ~~toured the country with PT Barnum’s circus~~ appeared at PT Barnum’s New York museum as one of the star attractions, always with the tamping iron on hand to amaze the crowds.

In the tradition of media circuses, the collectors have taken the long out-of-copyright photo, put a dirty great copyright sign across the front and are charging ‘usage fees’ for the undefaced version.

Phineas Gage may be dead, but the spirit of Barnum, it seems, lives on.

UPDATE: The LA Times has a short article and an undefaced version of the photo online.

Link to BPSRD on the photo.
Link to the ‘Meet Phineas Gage’ website with defaced photo.

Brain shaker

What modern home could not benefit from some brain-shaped porcelain salt and pepper shakers, I hear you ask. Apparently they even have magnets so the two hemisphere snap together into a whole brain.

Obviously, you’ll need to do an impromptu callosotomy to use them but at least you’ll have the fun of doing some split-brain experiments with your seasoning.

Not to be confused with AC/DC’s rather more saucy Brain Shake of course.

Link to brain salt and pepper shakers from Think Geek.

Street drugs and dopamine theory overdoses

Furious Seasons has alerted me to an interesting article in the Boston Globe about street dealing of the antipsychotic drug quetiapine – interesting because it reveals some of our prejudices about the neuroscience of recreational drug use.

One of the mantras of neuroscience is that drugs of abuse boost the dopamine system. This led to the somewhat bizarre headlines earlier this year that modafinil may be ‘addictive’ because it was found to increase dopamine function in the nucleus accumbens, a key part of the reward system.

The reason this was bizarre is because while there are many reports of people illicitly using the drug to avoid sleep and maintain focus, there are none about ‘modafinil addicts’. In fact, I couldn’t find a single case in the literature.

However, the ‘all drugs of abuse boost dopamine’ mantra trumped the fact that there aren’t any actual addicts to make people warn about its potential for addiction. And by people I don’t just mean the press, I mean the neuroscientists who carried out the research, including Nora Volkow, head of the US’s National Institute on Drug Abuse.

And this is why the reports of the abuse of quetiapine (trade name Seroquel), both in the popular press and in the medical literature, are so interesting, because quetiapine is a dopamine blocker.

In fact, it reduces function at the same D₂ dopamine receptors in exactly the same ‘reward circuits’ that are supposedly always stimulated by drugs of abuse.

In other words, it does exactly the opposite of what the received wisdom tell us, and yet, it is being widely abused to the point where people are getting gunned down over shady quetiapine deals.

As scientists one of our greatest vices is fitting the world into our theories, rather than fitting our theories to the world. For neuroscientists, this is especially tempting because society has come to the popular but false conclusion that brain-based explanations trump behavioural or psychological observations.

There is more to drug abuse and addiction than dopamine and our clich√©s about the ‘reward system’ are hampering our efforts to make sense of it all.

Link to Boston Globe article ‘Psychiatric drug sought on streets’.
Link to Furious Seasons who have been on the case for ages.

Is brain death, death?

The New Atlantis magazine has an in-depth article discussing the difficulty in defining death and why arguments about the brain have become central to understanding the final curtain.

The article is a little bit wordy in places but does a great job of exploring the philosophy of death definitions and why these have direct practical applications in medicine.

Not least in ‘pulling the plug’ decisions and the removal of organs from people who have been declared brain dead even while their body is still functioning on life support.

Another way forward is to confess that all this time the real reason why the neurological standard seemed palatable was that the patient with total brain failure has lost consciousness and will never regain it.

All the talk about the body no longer being a whole was just a distraction. The pulsing heartbeat, the warm skin, all the integrated work of the body‚Äîthese are indicators that the body is alive but not the person.

And it is the life of the person that demands protection, in this case from being made into a source for organs. This kind of dualism opens the door, of course, to the possibility that there are more ‚Äúpersonless‚Äù bodies‚Äîthat, for instance, some patients with severe dementia or PVS [persistent vegetative state] might meet the description.

Link to article ‘What and When Is Death?’

Encephalon 73 flickers into life

The 73rd edition of the Encephalon psychology and neuroscience writing carnival is here with a specially video enriched version, this time ably hosted on Channel N.

A couple of my favourites include Neurocritic tackling the myth of the depression gene and Providentia on the visionary psychosis surfer Emmanuel Swedenborg.

There’s many more excellent articles and a video to match each one so head on over and enjoy.

Link to Encephalon 73.

Unique like everyone else

You’ve probably heard of the many cognitive bias studies where the vast majority of people rate themselves as among the best. Like the fact that 88% of college students rate themselves in the top 50% of drivers, 95% of college professors think they do above average work, and so on.

In light of this, I’ve just found a wonderfully ironic study that found that the majority of people rate themselves as less susceptible to cognitive biases than the average person.

It’s work from psychologist Emily Pronin who studies insight into our own judgements and how it affects our social understanding and perception of others.

In this study, the participants (psychology students no less), were given a booklet explaining how cognitive biases work that described eight of the most common ones. They were then asked to rate how susceptible they were to each of the biases and then how susceptible the ‘average American’ was.

Each rated themselves as less affected by biases than other people, instantly causing an irony loop in the fabric of space and time.

The study also had a fantastic follow-up that demonstrated just how strongly these cognitive biases affect our thinking. Even when they’re pointed out, we can’t escape them:

Participants in one follow-up study who showed the better than-average bias insisted that their self-assessments were accurate and objective even after reading a description of how they could have been affected by the relevant bias.

Participants in a final study reported their peer’s self-serving attributions regarding test performance to be biased but their own similarly self-serving attributions to be free of bias.

Pronin calls this the ‘bias blind spot’ and you can read the full study online as a pdf file. Pronin also wrote an excellent 2008 review, also available as a pdf, on how these biases mean we see ourselves differently from how we see others, because we have direct access to our own minds but only observations of other people.

pdf of ‘bias blind spot’ study.
Link to DOI entry for same.

A reflector for violence

I don’t know what to make of this, but the discovery is quite startling. It’s data from a World Health Organisation study on lethal violence, finding that the ratio between murder and suicide differs between countries, and in some countries differs between sexes.

It suggests an interesting hypothesis, that cultural differences affect whether lethal violence is typically directed outwards (murder) or inwards (suicide). Skip to the findings if you just want the bottom line.

An Analysis of WHO Data on Lethal Violence: Relevance of the New Western Millennium.

Rezaeian M.

Asia Pac J Public Health. 2009 Jul 2. [Epub ahead of print]

INTRODUCTION: Suicide and homicide are considered to be lethal violent acts with a clear difference in their directions, that is, inwardly “killing oneself” or outwardly “killing another,” respectively. There are some studies in which these 2 violent acts are considered under the same framework mostly within Western countries. This article for the first time investigates this issue throughout the world. Material and methods. The present study uses data that have been estimated by Global Burden of Disease (GBD) project for 2000 for the 6 different regions of the world proposed by WHO. The suicide/homicide ratio has been calculated by dividing the suicide rate by the sum of the suicide and homicide rates within each age and sex groups.

FINDINGS. Three distinct groups have emerged. In the first group, that is, Southeast Asia, Europe, and Western Pacific, lethal violence in both males and females usually directs inward whereas in the second group, that is, Africa, lethal violence in both males and females directs outward. In the third group, that is, America and Eastern Mediterranean, in males lethal violence generally directs outward whereas in females it often directs inward.

CONCLUSION: Under the same framework if a factor causes external blame for the people’s failures it will increase the likelihood that the suicide/homicide ratio is expressed as homicide and vice versa. Although this might explain the observed pattern to some extent, more in-depth studies are needed to better understand the causal root of the pattern.

Link to PubMed entry for study.