At some point, the Mongol military leader Kublai Khan (1215–94) realized that his empire had grown so vast that he would never be able to see what it contained. To remedy this, he commissioned emissaries to travel to the empire’s distant reaches and convey back news of what he owned. Since his messengers returned with information from different distances and traveled at different rates (depending on weather, conflicts, and their fitness), the messages arrived at different times. Although no historians have addressed this issue, I imagine that the Great Khan was constantly forced to solve the same problem a human brain has to solve: what events in the empire occurred in which order?

Your brain, after all, is encased in darkness and silence in the vault of the skull. Its only contact with the outside world is via the electrical signals exiting and entering along the super-highways of nerve bundles. Because different types of sensory information (hearing, seeing, touch, and so on) are processed at different speeds by different neural architectures, your brain faces an enormous challenge: what is the best story that can be constructed about the outside world?

The days of thinking of time as a river—evenly flowing, always advancing—are over. Time perception, just like vision, is a construction of the brain and is shockingly easy to manipulate experimentally. We all know about optical illusions, in which things appear different from how they really are; less well known is the world of temporal illusions. When you begin to look for temporal illusions, they appear everywhere. In the movie theater, you perceive a series of static images as a smoothly flowing scene. Or perhaps you’ve noticed when glancing at a clock that the second hand sometimes appears to take longer than normal to move to its next position—as though the clock were momentarily frozen. (…)

Like vision, time perception is underpinned by a collaboration of separate neural mechanisms that usually work in concert but can be teased apart under the right circumstances. (…)

In the early days of television broadcasting, engineers worried about the problem of keeping audio and video signals synchronized. Then they accidentally discovered that they had around a hundred milliseconds of slop: As long as the signals arrived within this window, viewers’ brains would automatically resynchronize the signals; outside that tenth-of-a-second window, it suddenly looked like a badly dubbed movie.

This brief waiting period allows the visual system to discount the various delays imposed by the early stages; however, it has the disadvantage of pushing perception into the past. (…)

If I touch your toe and your nose at the same time, you will feel those touches as simultaneous. This is surprising, because the signal from your nose reaches your brain well before the signal from your toe. Why didn’t you feel the nose-touch when it first arrived? Did your brain wait to see what else might be coming up in the pipeline of the spinal cord unti lit was sure it had waited long enough for the slower signal from the toe? Strange as that sounds, it may be correct.

It may be that a unified polysensory perception of the world has to wait for the slowest overall information. Given conduction times along limbs, this leads to the bizarre but testable suggestion that tall people may live further in the past than short people. The consequence of waiting for temporally spread signals is that perception becomes something like the airing of a live television show. Such shows are not truly live but are delayed by a small window of time, in case editing becomes necessary.

Waiting to collect all the information solves part of the temporal-binding problem, but not all of it. A second problem is this: if the brain collects information from different senses in different areas and at different speeds, how does it determine how the signals are supposed to line up with one another? To illustrate the problem, snap your fingers in front of your face. The sight of your fingers and the sound of the snap appear simultaneous. But it turns out that impression is laboriously constructed by your brain. After all, your hearing and your vision process information at different speeds.

{ David M. Eagleman/Edge | Continue reading }

photo { Camilla Akrans }

Youngsters tend to live for the moment whilst older folks are more concerned about their futures. But when in a person’s life does this change in perspective usually occur? A new study identifies a period between the ages of thirteen and sixteen as being critical.

Laurence Steinberg and colleagues asked 935 people between the ages of ten and thirty years to answer questions regarding how much they think about the future, and to complete a time-discounting task. (…)

A key difference emerged between participants who were aged thirteen and younger versus those aged sixteen and older, with the older group being more future oriented.

{ BPS | Continue reading }

A single mega-colony of ants has colonised much of the world, scientists have discovered.

Argentine ants living in vast numbers across Europe, the US and Japan belong to the same inter-related colony, and will refuse to fight one another.

The colony may be the largest of its type ever known for any insect species, and could rival humans in the scale of its world domination.

What’s more, people are unwittingly helping the mega-colony stick together.

Argentine ants (Linepithema humile) were once native to South America. But people have unintentionally introduced the ants to all continents except Antarctica.

These introduced Argentine ants are renowned for forming large colonies, and for becoming a significant pest, attacking native animals and crops.

{ BBC | Continue reading }

Researchers in Italy had a female confederate visit a disco and approach 176 random people asking for a smoke. Clubbers were about twice as likely to hand one over if the request was directed at the right ear, whether or not the clubber was male or female. Whether these findings will hold good for other types of request is unknown.

These findings confirm previous studies which have found a right-ear preference for attending to and processing verbal stimuli. It is thought that this is because language is preferentially processed by the left side of the brain, which receives its input from the right ear. (…)

People’s preferred ear when using a telephone, though, has proved more controversial.

{ PsyBlog | Continue reading }

photo { Kate Moss by Michael Thompson }

The peak of the Spice Girls’ popularity has long passed, but Victoria Beckham – aka Posh Spice – still has massive media exposure. And Paris Hilton, who is famous for her lifestyle alone, makes world headlines daily.

A new psychology study helps explain why some stars burn bright, long, long after their talent has faded – if it ever was there to begin with.

Simply put, says Nathanael Fast of Stanford University in California, people need something to talk about. The human desire to find common ground in conversation pushes us to discuss already popular people, he says.

Fast’s team focused not on gossip column celebrities, but on professional baseball players in the US

“We realised that there’s a ton of stats and performance data available for baseball, so if we can show that famous or well-known baseball players become more prominent than unknown baseball players who perform just as well or better, we’re able to make a convincing case,” he says. (…)

Volunteers who were baseball fans themselves tended to pick an obscure player if they thought they were emailing an expert. Yet the same fans tended to converse about prominent players when they didn’t know anything about their correspondent.

“The very experts who could kind of inform everyone else don’t. They actually keep feeding them the information they already know because that helps establish a connection,” Fast says.

{ New Scientist | Continue reading }

Understanding the biology of mental illness would be a paradigm shift in our thinking about mind. It would not only inform us about some of the most devastating diseases of humankind but, because these are diseases of thought and feeling, it would also tell us more about who we are and how we function. I naively thought we were on the verge of such a paradigm change in 1983, when James Gusella and Nancy Wexler were tracking down the gene that causes Huntington’s disease. I expected that within 10 years we would have found the major genes that contribute to schizophrenia, depression, and autism. Since then, there has been a lot of enthusiasm about genes and mental illness and some false starts, but surprisingly little progress.

In the past few years, however, certain advances in genetics have given us new reasons for optimism. Now that we can look at the whole human genome, there is a logic to it that we could not appreciate when looking at genes in isolation. As a result, there is reason to believe that the next 10 to 20 years will be more fruitful than the past two decades have been. (…)

The most convincing scientific progress in psychiatry in the past decade has had little to do with genomics. It is the rigorous, scientific verification that certain forms of psychotherapy are effective. This is perhaps not surprising. One of the major insights in the modern biology of learning and memory is that education, experience, and social interactions affect the brain. When you learn something and then remember it for a long time, it’s because genes are being turned on and off in certain brain cells, leading to the growth of new synaptic contacts between the nerve cells of the brain. Insofar as psychotherapy works and produces stable, learned changes in behavior, it can cause stable anatomical changes in the brain.

{ Newsweek | Continue reading }

Assuming for a moment that birthdays are evenly distributed throughout the year, if you’re sitting in a room with forty people in it, what are the chances that two of those people have the same birthday?

For simplicity’s sake, we’ll ignore leap years. A reasonable, intelligent person might point out that the odds don’t reach 100% until there are 366 people in the room (the number of days in a year + 1)… and forty is about 11% of 366… so such a person might conclude that the odds of two people in forty sharing a birthday are about 11%. In reality, due to Math’s convoluted reasoning, the odds are about 90%. This phenomenon is known as the Birthday Paradox.

{ Damn Interesting | Continue reading }

Have to solve a problem? Try taking a nap.

But it has to be the right kind of nap — one that includes rapid eye movement, or REM, sleep, the kind that includes dreams. (…)

A nap that included REM sleep resulted in nearly a 40 percent improvement over the pre-nap performance.

{ NY Times | Continue reading }

photo { Lane Coder }

Since the declaration of Mahmoud Ahmadinejad’s landslide victory in Iran’s presidential election, accusations of fraud have swelled. Against expectations from pollsters and pundits alike, Ahmadinejad did surprisingly well in urban areas, including Tehran — where he is thought to be highly unpopular — and even Tabriz, the capital city of opposition candidate Mir Hussein Mousavi’s native East Azarbaijan province.

Others have pointed to the surprisingly poor performance of Mehdi Karroubi, another reform candidate, and particularly in his home province of Lorestan, where conservative candidates fared poorly in 2005, but where Ahmadinejad allegedly captured 71 percent of the vote. Eyebrows have been raised further by the relative consistency in Ahmadinejad’s vote share across Iran’s provinces, in spite of wide provincial variation in past elections.

These pieces of the story point in the direction of fraud, to be sure. They have led experts to speculate that the election results released by Iran’s Ministry of the Interior had been altered behind closed doors. But we don’t have to rely on suggestive evidence alone. We can use statistics more systematically to show that this is likely what happened. Here’s how.

We’ll concentrate on vote counts — the number of votes received by different candidates in different provinces — and in particular the last and second-to-last digits of these numbers. For example, if a candidate received 14,579 votes in a province (Mr. Karroubi’s actual vote count in Isfahan), we’ll focus on digits 7 and 9.
This may seem strange, because these digits usually don’t change who wins. In fact, last digits in a fair election don’t tell us anything about the candidates, the make-up of the electorate or the context of the election. They are random noise in the sense that a fair vote count is as likely to end in 1 as it is to end in 2, 3, 4, or any other numeral. But that’s exactly why they can serve as a litmus test for election fraud. For example, an election in which a majority of provincial vote counts ended in 5 would surely raise red flags.

Why would fraudulent numbers look any different? The reason is that humans are bad at making up numbers. Cognitive psychologists have found that study participants in lab experiments asked to write sequences of random digits will tend to select some digits more frequently than others.

So what can we make of Iran’s election results? We used the results released by the Ministry of the Interior and published on the web site of Press TV, a news channel funded by Iran’s government. The ministry provided data for 29 provinces, and we examined the number of votes each of the four main candidates — Ahmadinejad, Mousavi, Karroubi and Mohsen Rezai — is reported to have received in each of the provinces — a total of 116 numbers.

The numbers look suspicious. We find too many 7s and not enough 5s in the last digit.

{ Washington Post | Continue reading }

People tend to be poor judges of the quality of their memories. The circumstances in which eyewitnesses find themselves might render their recollections particularly untrustworthy, says Elizabeth Loftus, a professor of psychology at the University of California and a pioneer in the field of eyewitness research. “When it comes to brief episodes of memory, like in many criminal cases, poor lighting, passage of time, biased or suggestive questioning all can produce an erroneous memory,” she says.

{ Seed magazine | Continue reading }

photo { Pipilotti Rist, video still }

During production of the 1997 movie “Mimic,” American Humane Assn. representatives wandered through the Los Angeles set, ensuring that a herd of cockroaches was well taken care of. Licensed animal handlers were to follow state and federal anti-cruelty laws designed to protect the insects, which had been trained to swirl around actress Mira Sorvino’s feet. The roaches had to be fed at a certain time. They could only work a few hours each day. They could not be harmed.

At the same time, in studios in the San Fernando Valley, scores of other actors and actresses were working on movies. They put in long hours, commonly without meal breaks. They often worked without clean toilets, toilet paper, soap or water. More importantly, they were exposed to a host of infectious, and sometimes fatal, diseases.

These performers were making heterosexual adult films for an industry that in California is entirely legal, and utterly unregulated. Its producers take in several billion dollars annually from cable television programming, videos and Internet sites watched by a public whose appetite seems insatiable. They pay taxes, lobby in Sacramento and contribute to political campaigns.

Yet actors and actresses are discouraged from wearing prophylactics during filming because porn producers believe the public wants to see unprotected sex. So adult porn stars commonly engage in sexual acts with scores of partners, and then return each evening to their private lives–dating or having relationships with people across Southern California.

{ LA Times | Continue reading }

L.A. County health officials say at least 16 performers have been infected in addition to one reported this week. That brings the number of HIV cases in porn performers to 22 in the last five years.

{ LA Times | Continue reading }

Children with attention-deficit hyperactivity disorder might appear rowdy and indisciplined, but they are actually trying to cope with a faulty perception of time.

What to most of us seems like a short stretch of time would drag unbearably for someone with ADHD, says Katya Rubia of the Institute of Psychiatry at King’s College London. Her team’s research, reported this week, adds to a growing body of evidence for the importance of time perception in a wide range of psychological disorders.

ADHD affects around 5 per cent of children globally, most of them boys. Studies relating to the disorder have focused on patients’ short attention spans and impulsive behaviour. But ADHD is characterised by a shortage of dopamine, which is known to affect time perception, so Rubia and her colleagues wanted to know if this was the source of the kids’ problems.

{ NewScientist | Continue reading }

artwork { Morris Louis, Lambda II, 1960 | acrylic resin on canvas }