Month: October 2007

Artificial intelligence ‘sees’ visual illusion

A study just published in PLoS Computational Biology has reported that an artificial intelligence system trained to make sense of a simulated natural environment is susceptible to some of the same visual illusions that humans fall for.

In one of these, the ‘Herman grid‘ illusion – illustrated on the right, you may be able to ‘see’ fuzzy patches of grey in the white stripes, despite the fact that there is no grey in the image (click for a bigger version if it’s not clear).

David Corney and Beau Lotto, researchers working in the Lotto Lab (which has a wonderful website by the way), have been training artificial intelligence systems to distinguish surfaces in a simulated natural environment with lots of ‘dead leaf’-like shapes.

When training these sorts of systems, the idea is not to program them with specific rules, but to present an image and let the neural network make a guess.

The researchers then ‘tell’ the AI system whether it is correct in its guess, and it adjusts itself to try and reduce the extent of the error on the next guess. After many learning trials, these sorts of ‘back propagation‘ neural networks can make distinctions between quite complex stimuli.

In this case, Corney and Lotto decided that once the system was fully trained to complete its task successfully, they would test it with some visual illusions experienced by humans.

Interestingly, the AI system was susceptible to the Herman Grid illusion, sensing ‘grey’ where there was none. Other illusions produced similar results.

The fact that both humans and AI system ‘fall’ for the same illusions, suggests that they take advantage of visual abilities that have been shaped by our experience of the visual world.

Link to paper in PLoS Computational Biology (thanks Matt!).
Link to study write-up from the university’s news site.
Link to Lotto Lab website (with loads of cool images and demos).

Pioneers of psychology

Oklahoma State University’s online psychology museum has launched an exhibit to commemorate African American Pioneers of Psychology. It’s an excellent resource but they’re missing some photos and you might be able to help.

The photo on the left is of Dr Inez Prosser. She earned her PhD in educational psychology from the University of Cincinnati in 1933.

She did some of the earliest research into the effect of racial segregation on academic achievement.

There have been many more African-American psychologists who were working in the USA as far back as the 1920s and the new ‘Pioneers of Psychology’ site is collating their history.

Unfortunately, it’s missing photos for Drs Robert Prentiss Daniel and John Henry Brodhead.

If you think you can help out with photos of either of the above, or have additional information on any of the people featured in the exhibit, I am sure the curators would love to hear from you.

Link to African-American Pioneers of Psychology Website (via AHP).

Personality types, as you’ve never seen them before

Someone’s created some satirical descriptions of the personality types classified by the Myers-Briggs personality test, that include categories such as ‘The Egghead’, ‘The Conman’ and ‘The Evil Overlord’.

The Myers-Briggs isn’t used so much by research psychologists, largely because it isn’t as reliable as some of the newer ‘Big Five‘ personality measures which dominate the field.

It is not unusual for people to fill one in themselves though (there are many versions online) and get a rating of whether they are Extroverted or Introverted, Sensing or iNtuitive, Feeling or Thinking, Judging or Perceiving.

Each of these gets compressed into a short letter string, and each is supposed to represent some particular personality type.

This new satirical interpretation of the personality types makes a sly commentary on some of the more outlandish descriptions you can read online.

ESFP: The National Enquirer Headline

An ESFP is a spontaneous, outgoing, charismatic, fun-loving person like the guy you used to room with in college–you know, the one who was found floating face-down in the reservoir with the homecoming queen’s underwear in his teeth.

The strongest element of the psychological makeup of an ESFP is his easygoing, impulsive approach to life. ESFPs often build their careers out of dating supermodels, being involved in scandals, and appearing regularly in such newspapers as “The National Enquirer” and “The Weekly World News.” ESFPs often die in bizarre circumstances, usually involving jealous boyfriends, exotic dancers, escaped pythons, feather boas, and falls from the penthouse floor of high-rise apartments; those who don’t, usually die of veneral diseases.

Link to satirical Myers-Briggs interpretation (via MeFi).
Link to good Wikipedia page on the Myers-Briggs.

‘Self-silencing’ may affect women’s health

The New York Times discusses recent findings suggesting that not expressing feelings during marital arguments is bad for women’s health, but not for men’s.

The article draws on the results of a study that followed over 3,500 people and looked at both the quality of their marriage and whether they developed heart disease.

Interestingly, the overall level of marital satisfaction and total number of disagreements were not related to heart problems.

However, women who “self-silenced” during conflict with their spouse, compared with women who did not, had four times the risk of dying. This was not the case with men.

The tendency to bottle up feelings during a fight is known as self-silencing. For men, it may simply be a calculated but harmless decision to keep the peace. But when women stay quiet, it takes a surprising physical toll.

“When you’re suppressing communication and feelings during conflict with your husband, it’s doing something very negative to your physiology, and in the long term it will affect your health,” said Elaine Eaker, an epidemiologist in Gaithersburg, Md., who was the study’s lead author. “This doesn’t mean women should start throwing plates at their husbands, but there needs to be a safe environment where both spouses can equally communicate.”

Other studies led by Dana Crowley Jack, a professor of interdisciplinary studies at Western Washington University in Bellingham, Wash., have linked the self-silencing trait to numerous psychological and physical health risks, including depression, eating disorders and heart disease.

Keeping quiet during a fight with a spouse is something “we all have to do sometimes,” Dr. Jack said. “But we worry about the people who do it in a more extreme fashion.”

Nevertheless, men are not without their seemingly gender specific health risks. The study found that men with wives who were upset by work were almost three times more likely to develop heart disease.

The study is another example of how mental and physical health are completely intertwined.

Link to NYT article ‘Marital Spats, Taken to Heart’.
Link to abstract of scientific study.

How the brain generates private thoughts

The Spanish Journal of Psychology has an interesting English language article [pdf] on the neuropsychology of private thoughts – still one of the most mysterious and poorly understood aspects of our mental life.

Neuropsychology is especially good at looking at how differences in brain function relate to objectively observable behaviour. Private thoughts are quite hard to study in this way, because they are essentially subjective.

Sometimes, of course, we make our private thoughts ‘public’ by talking to ourselves, and, it seems, this is something we learn to do during childhood.

Infants seem unable to ‘think to themselves’ and instead ‘talk to themselves‘ when solving problems, usually vocalising the most tricky or novel aspects of the situation. As we grow, we develop the ability to internalise this speech, and can eventually have a purely internal monologue.

Understanding inner speech is also important because it becomes distorted in psychotic disorders such as schizophrenia.

People with psychosis can experience effects like ‘thought insertion’, where they experience external thoughts being inserted into their stream of consciousness, or ‘thought withdrawal’, where thoughts seem to be removed from the mind.

This suggests that there must be something that the brain uses to identify thoughts as self-generated, and that this perhaps breaks down in psychosis, so we can have the uncanny experience of having thoughts that don’t seem to be our own.

Why we would need this is an interesting question, as surely all thoughts would be our own.

However, the Spanish Journal of Psychology article notes that inner speech often activates areas of the brain also used for ‘outloud speech’, suggesting that it may be a sort of internal action.

Being able to distinguish bodily movements caused by something external (someone moving your arm) and movements caused by our own will is very important, and, perhaps, this is the sort of mechanism that becomes disturbed for what were originally movements, but have become internalised as we ‘think to ourselves’.

pdf of ‘A Neurocognitive Approach to the Study of Private Speech’.
Link to SciAm article on private speech in children.

Illusory motion with waves of almonds

I’ve just found a visual illusion that gives a striking impression of motion from a static image. It’s entitled ‘this picture is not animated’, which, like anything eye-catching on the internet, immediately made me check whether it was or not.

With many of these sorts of illusory motion images, you can ‘stop’ the motion by simplying viewing them through a very small aperture.

Putting a pin through a piece of paper and viewing it through the hole does the trick, but so does making a small viewing hole with your fingers.

As you can see yourself, the picture stops ‘moving’ when viewed like this, but starts again as soon as you view it normally.

This also prevents stars from twinkling when you view them at night. The traditional explanation of ‘star twinkle’ is that the light gets bounced around as it travels through the atmosphere, giving it the twinkling effect.

In fact, by looking at them through a small hole, you’re preventing any effects caused by your eyes moving about.

The fact that the illusion stops moving and the stars stop twinkling when you do this, suggests that the way our eyes scan across the visual scene is an important part of why we see the false movement in these sorts of images.

Because of this, you can ‘speed up’ and ‘slow down’ the false movement in the visual illusions by changing how often you move your eyes.

UPDATE: Thanks to celeriac for posting a link to a scientific paper which explains this effect.

Link to striking movement illusion.

The influencing machine in art and psychosis

The ever-excellent Fortean Times has an article about an exhibition that showed some of the most important works in the history of visionary and psychiatric art which depict the mysterious ‘influencing machine’.

The term was coined by psychoanalyst Viktor Tausk who noted that the delusions of people with schizophrenia often involved them being influenced by a ‘diabolical machine’, just outside the technical understanding of the victim, that influenced them from afar and is operated by a shadowy group of the person’s enemies.

The exhibition is partly drawn from the Prinzhorn Collection, which was started by the German psychiatrist Hans Prinzhorn who collected art work by asylum inpatients.

Unlike his contemporaries, he didn’t assume the interest was solely that the work reflected the mental state of the patient, but collected them for their aesthetic value and, in the process, discovered some amazingly creative artists.

His subsequent book, Artistry of the Mentally, was hugely influential and was an inspiration to Jean Dubuffet, who wanted to capture art as it appears ‘in the raw’, away from the influence of art schools and the art world.

Dubuffet began to collect what he called ‘art brut’ (raw art) and suggested that people who worked outside the art world were ‘outsider artists‘ – to which now whole galleries, magazines and academic conferences are devoted.

The Prinzhorn Collection and the Collection de l’Art Brut are now two of the most important collections in the world.

The Fortean Times article discusses a recent Prinzhorn exhibition that focused purely on the ‘influencing machine’, with some truly spectacular pieces from both mainstream and ‘outsider’ artists.

The exhibition is, appropriately, dominated by the Air Loom, the first known example of an influencing machine, which was detailed in eerily precise technical drawings between 1800 and 1810 by a Welsh tea-merchant named James Tilly Matthews, at that time confined in Bedlam (Bethlem) as an incurable lunatic.

Matthews’s plans showed a machine fuelled by barrels of magnetised gas and ‘putrid effluvia’, and powered by Leyden jars and windmill sails, that wove invisible mesmeric currents which, beamed at a human target by its sinister operators, filled the mind with alien voices and nightmarish visions and could be programmed to convulse, torture and even kill.

In an inspired and classically fortean move, the installation artist and crop circle pioneer Rod Dickinson has turned Matthews’s hallucinatory blueprints into reality. The result is an inscrutable piece that fills the main exhibition floor, towering ominously over the spectator. On one level, it’s a sober and ‘authentic’ assemblage of 18th-century technology, with oak panelling, brass fittings, hooped barrels and tanned leather tubes: a period piece, yet also brand new, as if fresh off the assembly line and poised to hiss and rumble into life.

As an aside, I was inspired by Tausk in a couple of papers I wrote on the interaction between psychosis and the net, where I discussed the appearance of the internet in paranoid delusions as the modern day incarnation of the influencing machine [pdf1, pdf2].

Link to Fortean Times article ‘Shadow of the Air Loom’.