Perception is a fundamentally underconstrained problem. You get information in through your senses, but not enough information to be absolutely sure of what is causing those sensations. A good example is perception of depth in vision. You get a pattern of light falling on your retinas (retinae?), in two dimensions, and from that you infer a three dimensional world, using various clever calculations of the visual system and some assumptions about what is likely. But because the process remains fundamentally underconstrained, there is always the possibility that you will see something that isn’t really there – that is, your visual system will take in a pattern of information and decide that it is more likely to be produced by a scenario different from the real one.
Which is a all a long winded way of saying: “Look, cool! Illusions rooms!” (thanks Yalda)
They’re painted so that from one particular angle the shapes line up and your visual system flips into thinking that it can see a flat, 2D, pattern when the reality is a disjoint 3D one. Awesome.
There’s plenty more here
Eating disorders, such as anorexia, are traditionally thought to be driven by a distorted body image, so affected people see themselves as excessively overweight (and therefore unattractive) despite being very thin.
A recent study by psychologist Anita Jansen and colleagues has challenged this theory, by showing that women with eating disorders are actually more accurate at judging how attractive they are to others, whereas unaffected women typically over-estimate their attractiveness.
Jansen’s team asked women with and without eating disorder symptoms to have their picture taken, from the neck down, in their underwear. They were then asked to rate their own body for general attractiveness, and say which was the most attractive and unattractive part of their body.
These anonymised photos were then shown to two panels, consisting of both males and females, who were asked to make the same ratings.
The women with symptoms were generally in agreement with the panels, whereas those without rated themselves as more attractive and typically did not agree on which were their most and least attractive body parts.
This shows a lack of a ‘self serving attribution bias’ which is a normal tendency to over-attribute positive things to ourselves and negative things to other people or situations.
A recent review of the research suggested that this bias is usually strongly present in most people. It has been suggested that this may be useful, as it might emotionally cushion us from some of life’s hardships.
People with certain forms of mental illness, particularly depression, tend not to have this bias, however, meaning they actually view the world more accurately – an effect coined ‘depressive realism‘.
Jansen’s study suggests a similar ‘painful realism’ effect may be present in people with eating disorders, although it’s not clear whether this is specific to body perception, or whether it is primarily associated with emotional difficulties that often accompany conditions like anorexia.
UPDATE: World of Psychology has interesting commentary on this research (and post).
If you were designing an advert to encourage university students to drink less alcohol, which wording do you think would work better?
“Most university students drink too much, with dire consequences for their future health”.
“University students are healthier than you think, most have fewer than four drinks when they go out”.
A growing body of research on the misperception of norms suggests the second type of statement may work better. University students consistently overestimate how much their peers drink, and importantly, it’s this misperception that correlates with how much they choose to drink themselves.
“In point of fact, the norm among college students is to drink moderately if at all. And promoting this good news is an essential element of the health promotion strategy known as the social norms approach”.
From an article in The Scientist magazine on the science of encouraging healthy behaviour. (Note, to celebrate their relaunch, all 20 years of content is currently accessible for free at The Scientist website).
I’m currently enjoying reading the Brain Ethics Blog that aims to discuss the consequences of brain science amd the ethical issues that arise from it.
It is run by two Danish neuropsychologists, Thomas Zo√´ga Rams√∏y and Martin Skov, who give their own take on the current hot topics of mind and brain science.
The most recent post, analysing a recent study that claims to have made inferences about cognitive evolution from a brain scanning experiment, particularly caught my eye as an insightful look into a recent controversial finding.
Link to Brain Ethics Blog.
Science and Consciousness Review have an interview with neuroscientist Sara Lazar, who conducted the first fMRI study of meditation in 2000, and recently hit the news for reporting that meditation may increase the thickness of the grey matter in the cortex.
The interview explores Sara’s motivation for studying meditation, and discusses the science and implications of her work.
When we first posted about the meditation study, one of the criticisms was that the study simply compared meditators to non-meditators without following them up to actually see if the cortex did change over time.
It could be argued that people with more grey matter are simply more likely to meditate, rather than the act of meditation having any direct effect on grey matter.
Like the London cab driver study (which reported that cab drivers have larger hippocampi) Lazar’s meditation study reported a correlation between number of years spent meditating and the amount of grey matter, making it much less likely that the effect was incidental.
Lazar discusses such results in detail and, particularly, focuses on the brain areas found to show the most change, and relates them to the possible effects meditation may be having on the brain’s function.
Link to interview with Dr. Sara W. Lazar.
The band of reality skeptics over at The Huge Entity have finished their series of Reasons Why You Don’t Exist.
As we mentioned previously, there’s a contribution from our very own Christian Jarret, and a number of other authors pushing their own brand of mind altering concepts.
Jaime Morrison argues with himself on the reliability of information provided by perception and comes to the conclusion that neither of him exists, and Daniel Rourke questions whether the world as we experience it is just another reality-bending trick the brain has evolved to use.
…and there’s more where those came from.
Link to ‘Reasons Why You Don’t Exist’.
ABC Radio’s All in the Mind discusses the curious condition of prosopagnosia, sometimes called ‘face-blindness’, where affected individuals can’t recognise faces despite having intact vision and being able to recognise objects.
The programme discusses how face recognition can be affected after brain injury, and talks to both a person with the condition, and neuropsychologists trying to better understand how it occurs.
On a related note, last year we interviewed Thomas Gr√ºter, a prosopagnosia researcher and someone who has an inherited version of the disorder.
As the cold winter evenings drew near
Aunt Marge used to put extra blankets
over the furniture, to keep it warm and cosy
Mussolini was her lover, and life
was an outoffocus rosy-tinted spectacle
but neurological experts
with kind blueeyes
and gentle voices
small white hands
and large Rolls Royces
said that electric shock treatment
should do the trick
today after 15 years of therapeutic tears
and an awful lot of ratepayers’ shillings
down the hospital meter
sad Aunt Marge
no longer tucks up the furniture
before kissing it goodnight
that her affair with Mussolini
clearly was not right
particularly in the light
of her recently announced engagement
to the late pope.
‘Sad Aunt Marge’ by poet Roger McGough, from his book Blazing Fruit: Selected Poems 1967-1987 (ISBN 0140586520).
The series, made by producer Adam Curtis, follows the development of the concept of the self from the ideas of Freud, to the massively influential but largely unknown role of his nephew Edward Bernays.
Bernays is considered the ‘father of public relations’ as he virtually invented the practice in its current form by applying his uncle’s theories.
Crucially, instead of selling products on the basis that they were better products, he revolutionised advertising by marketing them to appeal to the sense of self – i.e. the product would make you a better person (more attractive, more independent or whatever).
He was later involved in applying the same techniques to excert political influence on behalf of the US government and later wrote Propaganda, one of the most influential books on the subject.
The documentary tracks how the psychology of the ‘self’ evolved and was used by marketeers and politicians throughout the 20th century.
It gets a little political towards the end, but otherwise strikes me as a groundbreaking analysis of a neglected topic. Highly recommended.
An interesting update on Peter Lawrence’s PLoS Biology article that discussed the role of social and biological differences between males and females, and the under-representation of women in science (see previously on Mind Hacks)…
According to an article in The Telegraph, Lawrence’s article was accepted for publication in the journal Science but they bottled it and pulled out at the eleventh hour, presumably fearing the controversy that has surrounded the debate so far.
Link to Telegraph article ‘Scientists are split on the different ways men and women think’.
This week’s Science News has a cover article on the neural basis of the sense of self, which they’ve kindly published online in full.
The article also discusses how the concept of self can breakdown after brain injury or during mental illness. For example, some people diagnosed with schizophrenia have the experience that they are being controlled by outside forces.
In addition to the article, there was a recent edition WNYC’s Radio Lab that covered similar ground, as noted in a previous post on Mind Hacks.
Link to article ‘Self-Serve Brains’ from Science News.
Quick links from the past week in mind and brain news:
Research suggests that complex decisions should be ‘slept-on’ whereas simple decisions such as “selecting a brand of oven glove” (huh?) can be left to the conscious mind.
Japan sees a surge of death from people who make ‘internet suicide pacts‘, reports the BBC.
Wired discusses research on the biases in interpreting emotional tone from other people’s emails.
An article in The Manitoban discusses the science and validity of parapsychology [Ghostbusters fans: make your own jokes about Manitoban’s Spirit Guide here].
Nature report on research that suggests that the more familiar you are with a route, the longer it seems.
Stanford neuroscientist Bill Newsome wants to implant an electrode in his brain to better understand human consciousness. Cool!
Circadiana discusses the disrupting effect of puberty and menstruation onset on sleep patterns.
Seed Magazine have an online article looking at the role of mirror neurons in appreciating spectator sport, particularly in light of the ongoing Winter Olympics.
The article itself is quite speculative, taking some of the conclusions with regard to possible emotional identification with the competitors a little further than the evidence can strongly support, but deftly uses the example of sports as an interesting introduction to the function of the ‘mirror system’.
Link to article ‘Built to be fans’.
The cover article in this week’s New Scientist is about the new generation of wakefulness-promoting and cognitive enhancement drugs being marketed and developed by pharmaceutical companies.
Although marketed as a treatment for narcolepsy, modafinil is being frequently used by people wanting more work or play time without the cognitive impairement associated with tiredness. This has become so prevalent that it featured in a major article in the Washington Post as far back as 2002.
The New Scientist article is also enthusiastic in its coverage of the new compounds:
If that sounds unlikely, think about what is already here. Modafinil has made it possible to have 48 hours of continuous wakefulness with few, if any, ill effects. New classes of sleeping pills are on the horizon that promise to deliver sleep that is deeper and more refreshing than the real thing. Further down the line are even more radical interventions – wakefulness promoters that can safely abolish sleep for several days at a stretch, and sleeping pills that deliver what feels like 8 hours of sleep in half the time. Nor is it all about drugs: one research team even talks about developing a wearable electrical device that can wake your brain up at the flick of a switch.
Although perhaps we can be a bit suspicious of the claim that they have “few, if any, ill effects”, as the history of new drugs shows that major effects are often not discovered until several years after the marketing claims them to be virtually side-effect free (e.g. benzodiazepines, SSRIs).
Unfortunately, the New Scientist article is not available online to non-subscribers, so you’ll have to visit your local library or newsagent to get a copy, but there’s plenty of information on modafinil and CX717 on the net.