Researchers are looking for a scientific answer to explain why children think they actually disappear when they cover their eyes while playing peekaboo.

Researchers led by James Russell at the University of Cambridge have carried out the first study into this bizarre trait with groups of three and four-year-old children.

The children's eyes were covered with masks and they were then asked whether they could be seen by the researchers - with most saying no.

Many also believed that the researchers could not see adults who were wearing eye masks - leading to the conclusion most young children believe that anyone who covers their eyes is obscured from other people's view.

© Chris ReaumeThis shows a fruit fly feeding. A genetic study by evolutionary biologists at the University of Toronto using fruit flies (Drosophila melanogaster) showed that chronic food deprivation and lack of adequate nutrition in early life had significant impact on adult behavior and quality of life.

Study part of growing body of knowledge surrounding gene-environment interplay.

It is time to put the nature versus nurture debate to rest and embrace growing evidence that it is the interaction between biology and environment in early life that influences human development, according to a series of studies recently published in a special edition of the Proceedings of the National Academy of Sciences (PNAS).

"Biologists used to think that our differences are pre-programmed in our genes, while psychologists argued that babies are born with a blank slate and their experience writes on it to shape them into the adults they become. Instead, the important question to be asking is, 'How is our experience in early life getting embedded in our biology?'" says University of Toronto behavioural geneticist Marla Sokolowski. She is co-editor of the PNAS special edition titled "Biological Embedding of Early Social Adversity: From Fruit Flies to Kindergarteners" along with professors Tom Boyce (University of British Columbia) and Gene Robinson (University of Illinois).

Sokolowski, who is a University Professor in the Department of Ecology & Evolutionary Biology (EEB), the inaugural academic director of Uof T's Fraser Mustard Institute for Human Development and co-director of the Experience-based Brain and Biological Development Program (EBBD) at the Canadian Institute for Advanced Research (CIFAR) says that relatively little is known about the gene-environment interplay that underlies the impact of early life adversity on adult health and behaviour.

Vulnerability to major depression is linked with how satisfied we are with our lives. This association is largely due to genes.

This is the main finding of a new twin study from the Norwegian Institute of Public Health in collaboration with the University of Oslo. The researchers compared longitudinal information from identical and fraternal twins to determine how vulnerability to major depression is associated with dispositional (overall) lifetime satisfaction.

Previous studies have systematically shown that life satisfaction is considerably stable over time. People who are satisfied at any one point in life are often also satisfied at other times in their lives. This stability - the dispositional life satisfaction - is often said to reflect an underlying positive mood or a positive disposition. Previous studies have also shown that people with such a positive disposition are less depressed, but very few studies have examined the mechanisms behind this relationship.

There are few more fascinating and mind-bending frontiers in fields of neuroscience and psychology than the study of how the brain perceives time. While symphonies, stock markets and our daily schedules are conveniently constructed around the well-defined, predictable progression of what might be called 'objective time', our brains take a much more flexible approach to dealing with passing events, stretching, condensing and generally distorting our perception of time in response to a variety of external and internal factors.

In fact, brain time - or our mind's perception of time - is an inherently subjective phenomenon. And it is perhaps never more subjective than when we are confronted with events that bring about a strong emotional response. Numerous studies in recent decades have repeatedly highlighted the fact that both our spatial perception and time perception can be measurably affected by negative or positive emotional experiences.

For instance, study subjects who are shown images that the brain associates with intensely positive experiences - like, say, erotic scenes - will consistently report that these images flit by more quickly than intensely negative pictures such as a grisly murder scene, even when both images are displayed for the exact same length of time.

"We imagine that we're perfect at judging time, but we're not," says Simona Buetti, a postdoctoral researcher in psychology at the University of Illinois at Urbana-Champaign. "If you see a disgusting image, like a photo of a mutilated body, you will perceive this image lasting longer than if you see a picture of people on a roller coaster, or an erotic image."

Buetti and her colleague Alejandro Lleras recently set out to see if they could offset the brain's tendency to distort time in emotionally intense situations. The results of their study, published in the online journal Frontiers in Psychology, demonstrate that this stretching and shortening of perceived time can be corrected simply by making a person feel that they are in control of the situation.

When do we first learn to express empathy? That's a question psychologists have been probing for some time by, among other things, examining when we learn to imitate yawns. Dogs, too, have been found in some studies to yawn when their owners yawn, but does it mean they're feeling empathy for the ones who care for them?

Scientists first came to the conclusion that "yawn contagion" -- as they call it -- was related to human empathy when they found that toddlers didn't have it. Research suggests kids learn to yawn in response to others beginning at age four; that's also when a number of cognitive abilities, such as reading emotional cues from facial expressions, begin to manifest themselves.

Is it possible that puppies also have to learn that yawns are contagious? A new study published in the journal Animal Cognition suggests yes. Swedish researchers selected 35 ordinary house dogs of various breeds between 4 and 14 months of age and sat them in front of their owners to see whether they would respond to fake yawns -- a gaping mouth with no sounds such as inhaling and exhaling of air -- and to realistic yawns that seemed convincing.

Cyberbullying - the use of the Internet, phones or other technologies to repeatedly harass or mistreat peers - is often linked with teen suicide in media reports. However, new research presented on Saturday, Oct. 20, at the American Academy of Pediatrics (AAP) National Conference and Exhibition in New Orleans, shows that the reality is more complex. Most teen suicide victims are bullied both online and in school, and many suicide victims also suffer from depression.

For the abstract, "Cyberbullying and Suicide: A Retrospective Analysis of 41 Cases," researchers searched the Internet for reports of youth suicides where cyberbullying was a reported factor. Information about demographics and the event itself were then collected through searches of online news media and social networks. Finally, descriptive statistics were used to assess the rate of pre-existing mental illness, the co-occurrence of other forms of bullying, and the characteristics of the electronic media associated with each suicide case.

The study identified 41 suicide cases (24 female, 17 male, ages 13 to 18) from the U.S., Canada, the United Kingdom and Australia. In the study, 24 percent of teens were the victims of homophobic bullying, including the 12 percent of teens identified as homosexual and another 12 percent of teens who were identified as heterosexual or of unknown sexual preference.

Wouldn't it be amazing if our bodies prepared us for future events that could be very important to us, even if there's no clue about what those events will be?

Presentiment without any external clues may, in fact, exist, according to new Northwestern University research that analyzes the results of 26 studies published between 1978 and 2010.

Researchers already know that our subconscious minds sometimes know more than our conscious minds. Physiological measures of subconscious arousal, for instance, tend to show up before conscious awareness that a deck of cards is stacked against us.

"What hasn't been clear is whether humans have the ability to predict future important events even without any clues as to what might happen," said Julia Mossbridge, lead author of the study and research associate in the Visual Perception, Cognition and Neuroscience Laboratory at Northwestern.

A person playing a video game at work while wearing headphones, for example, can't hear when his or her boss is coming around the corner.

Some people may actually see sounds, say researchers who found this odd ability is possible when the parts of the brain devoted to vision are small.

These findings points to a clever strategy the brain might use when vision is unreliable, investigators added.

Scientists took a closer look at the sound-induced flash illusion. When a single flash is followed by two bleeps, people sometimes also see two illusory consecutive flashes.

Past experiments revealed there are strong differences between individuals when it comes to how prone they are to this illusion. "Some would experience it almost every time a flash was accompanied by two bleeps, others would almost never see the second flash," said researcher Benjamin de Haas, a neuroscientist at University College London.

These differences suggested to de Haas and his colleagues that maybe variations in brain anatomy were behind who saw the illusion and who did not. To find out, the researchers analyzed the brains of 29 volunteers with magnetic resonance imaging (MRI) and tested them with flashes and bleeps.

New neuroscience research is confirming an old adage about the power of a handshake: strangers do form a better impression of those who proffer their hand in greeting. The study was led by Beckman Institute researcher Florin Dolcos and Department of Psychology postdoctoral research associate Sanda Dolcos.

New neuroscience research is confirming an old adage about the power of a handshake: strangers do form a better impression of those who proffer their hand in greeting.

A firm, friendly handshake has long been recommended in the business world as a way to make a good first impression, and the greeting is thought to date to ancient times as a way of showing a stranger you had no weapons. Now, a paper published online and for the December print issue of the Journal of Cognitive Neuroscience on a study of the neural correlates of a handshake is giving insight into just how important the practice is to the evaluations we make of subsequent social interactions.

The study was led by Beckman Institute researcher Florin Dolcos and Department of Psychology postdoctoral research associate Sanda Dolcos. They found, as they wrote, that "a handshake preceding social interaction enhanced the positive impact of approach and diminished the negative impact of avoidance behavior on the evaluation of social interaction."

Their results, for the first time, give a scientific underpinning to long-held beliefs about the important role a handshake plays in social or business interactions. Sanda Dolcos said their findings have obvious implications for those who want to make a good impression.

Are left-handed people smarter, more artistic or just plain clumsier?

About 10 per cent of the population is left handed and many more of us switch between our hands for various tasks. Yet left-handers have been discriminated against since ancient times and many myths surround this difference.

In fact, most of the popular beliefs about left-handers rarely stand up to close scrutiny, none more so than the belief that they tend to be a little clumsy.

It may appear so, but that's only because most of the world's tools, sporting equipment and musical instruments are designed by right handers for use by right-handers.

An awkward world

Everything from the angle of scissor blades to the turn of corkscrews and the placement of camera buttons favours the right-handed.

So do buttons - at least for men. Ever wondered why women's buttons do up on the left side? It's a relic from the time when right-handed maids helped their mistresses to dress.

More seriously, many power tools and heavy machines can be dangerous because left-handers find it difficult to reach the on/off switch and hold equipment steady.

The upside of this is that many left-handers learn to quickly adapt to items designed for right-handers and this sometimes leads to a heightened manual dexterity in approaching new tasks.

Living in a right-handed world can sometimes be a boon for the left-handed.

According to the Victorian government's Better Health Channel, "The sporting advantage includes taking the right-handed opponent by surprise. Right-handed athletes aren't used to playing against left-handed opponents."

Writing has traditionally been more difficult for left-handers due to smudging. But the modern world favours lefties, who have an advantage with QWERTY computer keyboards.

Some 56 per cent of keystrokes are made with the left hand and 3,000 words in English can be typed entirely with the left hand. Only 300 words are entirely right-handed.