In the famous "marshmallow experiment" four decades ago, researchers at Stanford University presented more than 600 four-year-olds with a marshmallow and told the kids that if they could resist eating it for an unspecified amount of time (actually 15 minutes), they would get two marshmallows.

Researchers followed up with the participants over the next several years and found that those who were able to wait for the second marshmallow as children tended to enjoy more success later in life, from higher scores on their SATs to lower body mass index.

A new small study that plays on this experiment suggests that the ability to delay gratification might be impacted as much by the environment as by innate self-control.

"Being able to delay gratification - in this case to wait 15 difficult minutes to earn a second marshmallow - not only reflects a child's capacity for self-control, it also reflects their belief about the practicality of waiting," the new study's lead author, Celeste Kidd, a doctoral student at the University of Rochester, said in a statement. "Delaying gratification is only the rational choice if the child believes a second marshmallow is likely to be delivered after a reasonably short delay."

In the study, Kidd and her team gave 28 children, age three to five, a piece of paper to decorate for a create-your-own-cup kit.

If you've ever had to make a snap decision between two unfamiliar choices, you may want to thank your subconscious for making it possible. According to new research, the brain's memory areas link new memories to old associations, providing a roadmap for decision-making we don't even realize we have.

The research, published in the Oct. 12 issue of the journal Science, focuses on the hippocampus, a region nestled deep in the brain that helps consolidate memories. Scientists have long known the hippocampus links memories and integrates them together, but the new study is the first to look at the region's role in biasing the brain toward certain choices.

People are faced with new choices all the time: two new cereals in the grocery store, for example, or two unknown routes on the GPS. Without any previous history to draw on, how do people make these decisions?

Testing the subconscious

Columbia University psychologists G. Elliott Wimmer and Daphna Shohamy decided to find out. They had 28 people complete a series of three tasks while in a functional magnetic resonance imaging (fMRI) machine. First, the participants saw pairs of images flashed up on a computer screen in the fMRI. One image was a picture of either a face, body part or landscape. The other was a circle with a colorful, psychedelic pattern inside.

The same circle was always shown with the same image, so that participants would learn that the two went together. Next, the researchers flashed images of only the psychedelic circles. For half of the circles, participants were told they would get a $1 reward for viewing these.

After the participants had learned to associate certain circle patterns with money, the researchers put up another series of paired images. This time, participants saw either two psychedelic circles or two of the original body part, face or landscape pictures. They were then told to pick one of the two for a chance to win another prize.

Throughout the experiment, the fMRI measured the blood flow to individual brain regions, a way to quantify brain activity in each region.

Women are more affected by bad news and can also remember the details better than their male counterparts, according to new research. The study, which is one of the first to look at the body's response to negative media, included 60 men and women who were shown news articles of accidents and murders.

Researchers found that women react to bad news with more stress than men. They say that the reason could be that women are more empathetic and have evolved to be more vigilant and think about situations that threaten them and their children.

Canadian researchers from the University of Montreal gave participants a selection of articles from Montreal's newspapers. Some of the articles were judged to be emotionally neutral, like a story about a film premiere or the opening of a new bridge, and others were more upsetting about events such as murders or accidents.

Researchers took saliva samples from the participants before and after they read the stories to check for any changes in levels of the stress hormone cortisol.

The next day, researchers had asked participants recall as many of the news headlines from the day before. They found that while women and men remembered the neutral stories at about the same rate, women were twice as likely as men to remember negative stories.

A study from the University of Granada based on police surveys indicates that in domestic violence crimes in which the woman kills her abuser, if she is more attractive she is perceived as guiltier.

From a social psychology point of view, it has been noticed that physical attractiveness has an influence on how people are perceived by others in labour, academic and even legal fields. On the one hand, this creates the mental association of "what is beautiful is good". On the other hand though, when it comes to domestic violence the results are different.

"One of the most interesting conclusions of the study was that when the woman accused of killing her abuser was attractive, participants attached greater culpability, whereas if considered 'unattractive', this decreases," as explained to SINC by Antonio Herrera, Inmaculada Valor-Segura and Francisca Expósito, the authors of the study published in The European Journal of Psychology Applied to Legal Context.

For the purposes of the study, two types of 'mock' stories about legal proceedings were invented in which the defendant was a woman accused of killing her husband. Her defence was that she had suffered prolonged domestic violence and thus acted in self-defence when killing him. In one of the stories the description of the woman coincided with the prototypical battered woman but in the other it did not.

Learning a new language makes the brain grow, according to a new study. Swedish scientists studied young recruits at the Swedish Armed Forces Interpreter Academy by measuring the brains of participants before and after the language training.

Students accepted to the academy typically go from having no knowledge of a language such as Arabic, Russian or Mandarin to speaking it fluently after 13 months. Recruits at this academy study from morning to evening, weekdays and weekends and the recruits study at a pace quicker than any other language course.

Researchers compared students at the language academy with a control group made up of medicine and cognitive science students at Umeå University. Researchers explained that the non-language students at the university still studied hard, but not languages.

Both groups had undergone MRI scans before and after a three-month period of intensive study. Results of the study show that while the brain structure of the control group remained unchanged, specific parts of the brain of language students grew. Researchers found the hippocampus, which is a deep-lying brain structure that is involved in learning new material and spatial navigation, and some areas in the cerebral cortex grew in size after three months of an intensive language course.

"We were surprised that different parts of the brain developed to different degrees depending on how well the students performed and how much effort they had had to put in to keep up with the course," researcher Johan Mårtensson, of Lund University, Sweden, said in a statement.

UCLA researchers have for the first time measured the activity of a brain region known to be involved in learning, memory and Alzheimer's disease during sleep. They discovered that this part of the brain behaves as if it's remembering something, even under anesthesia, a finding that counters conventional theories about memory consolidation during sleep.

The research team simultaneously measured the activity of single neurons from multiple parts of the brain involved in memory formation. The technique allowed them to determine which brain region was activating other areas of the brain and how that activation was spreading, said study senior author Mayank R. Mehta, a professor of neurophysics in UCLA's departments of neurology, neurobiology, physics and astronomy.

In particular, Mehta and his team looked at three connected brain regions in mice - the new brain or the neocortex, the old brain or the hippocampus, and the entorhinal cortex, an intermediate brain that connects the new and the old brains. While previous studies have suggested that the dialogue between the old and the new brain during sleep was critical for memory formation, researchers had not investigated the contribution of the entorhinal cortex to this conversation, which turned out to be a game changer, Mehta said. His team found that the entorhinal cortex showed what is called persistent activity, which is thought to mediate working memory during waking life, for example when people pay close attention to remember things temporarily, such as recalling a phone number or following directions.

"The big surprise here is that this kind of persistent activity is happening during sleep, pretty much all the time." Mehta said. "These results are entirely novel and surprising. In fact, this working memory-like persistent activity occurred in the entorhinal cortex even under anesthesia."

The study appears Oct. 7, 2012 in the early online edition of the journal Nature Neuroscience.

The findings are important, Mehta said, because humans spend one-third of their lives sleeping and a lack of sleep results in adverse effects on health, including learning and memory problems.

As a neurosurgeon, I did not believe in the phenomenon of near-death experiences. I grew up in a scientific world, the son of a neurosurgeon. I followed my father's path and became an academic neurosurgeon, teaching at Harvard Medical School and other universities. I understand what happens to the brain when people are near death, and I had always believed there were good scientific explanations for the heavenly out-of-body journeys described by those who narrowly escaped death.

The brain is an astonishingly sophisticated but extremely delicate mechanism. Reduce the amount of oxygen it receives by the smallest amount and it will react. It was no big surprise that people who had undergone severe trauma would return from their experiences with strange stories. But that didn't mean they had journeyed anywhere real.

Although I considered myself a faithful Christian, I was so more in name than in actual belief. I didn't begrudge those who wanted to believe that Jesus was more than simply a good man who had suffered at the hands of the world. I sympathized deeply with those who wanted to believe that there was a God somewhere out there who loved us unconditionally. In fact, I envied such people the security that those beliefs no doubt provided. But as a scientist, I simply knew better than to believe them myself.

In the fall of 2008, however, after seven days in a coma during which the human part of my brain, the neocortex, was inactivated, I experienced something so profound that it gave me a scientific reason to believe in consciousness after death.

I know how pronouncements like mine sound to skeptics, so I will tell my story with the logic and language of the scientist I am.

Very early one morning four years ago, I awoke with an extremely intense headache. Within hours, my entire cortex - the part of the brain that controls thought and emotion and that in essence makes us human - had shut down. Doctors at Lynchburg General Hospital in Virginia, a hospital where I myself worked as a neurosurgeon, determined that I had somehow contracted a very rare bacterial meningitis that mostly attacks newborns. E. coli bacteria had penetrated my cerebrospinal fluid and were eating my brain.

When I entered the emergency room that morning, my chances of survival in anything beyond a vegetative state were already low. They soon sank to near nonexistent. For seven days I lay in a deep coma, my body unresponsive, my higher-order brain functions totally offline.

Then, on the morning of my seventh day in the hospital, as my doctors weighed whether to discontinue treatment, my eyes popped open.

Swedish researchers at Uppsala University have, together with Brazilian collaborators, discovered a new group of nerve cells that regulate processes of learning and memory. These cells act as gatekeepers and carry a receptor for nicotine, which can explain our ability to remember and sort information.

The discovery of the gatekeeper cells, which are part of a memory network together with several other nerve cells in the hippocampus, reveal new fundamental knowledge about learning and memory. The study is published today in Nature Neuroscience.

The hippocampus is an area of the brain that is important for consolidation of information into memories and helps us to learn new things. The newly discovered gatekeeper nerve cells, also called OLM-alpha2 cells, provide an explanation to how the flow of information is controlled in the hippocampus.

"It is known that nicotine improves cognitive processes including learning and memory, but this is the first time that an identified nerve cell population is linked to the effects of nicotine", says Professor Klas Kullander at Scilifelab and Uppsala University.

Humans think, learn and memorize with the help of nerve cells sending signals between each other. Some nerve cells send signals far away to other areas of the brain, while other neurons send signals within the same area. Local nerve circuits in the hippocampus process impressions and turn some of them into memories. But how does this work? And how can nicotine improve this mechanism?

Do you think like a psychopath? It has been claimed that one quick way of telling is to read the following story and see what answer to its final question first pops into your head:

While attending her mother's funeral, a woman meets a man she's never seen before. She quickly believes him to be her soulmate and falls head over heels. But she forgets to ask for his number, and when the wake is over, try as she might, she can't track him down. A few days later she murders her sister. Why?

If the first answer that springs to your mind is some variation of jealousy and revenge - she discovers her sister has been seeing the man behind her back - then you are in the clear. But if your first response to this puzzle is "because she was hoping the man would turn up to her sister's funeral as well", then by some accounts you have the qualities that might qualify you to be a cold-blooded killer - or a captain of industry, a nerveless surgeon, a recruit for the SAS - or which may well make you a commission-rich salesman, a winning barrister, a charismatic clergyman or a red-top journalist. The little parable purports to reveal those qualities - an absence of emotion in decision making, a cold focus on outcomes, an extremely ruthless and egocentric logic - which tend to show up in disproportionate degrees in all those individuals.

Hate the Lakers? Do the Celtics make you want to hurl? Whether you like someone can affect how your brain processes their actions, according to new research from the Brain and Creativity Institute at USC.

Most of the time, watching someone else move causes a 'mirroring' effect - that is, the parts of our brains responsible for motor skills are activated by watching someone else in action.

But a study by USC researchers appearing Oct. 5 in PLOS ONE shows that whether or not you like the person you're watching can actually have an effect on brain activity related to motor actions and lead to "differential processing" - for example, thinking the person you dislike is moving more slowly than they actually are.

"We address the basic question of whether social factors influence our perception of simple actions," says Lisa Aziz-Zadeh, an assistant professor with the Brain and Creativity Institute at USC and the Division of Occupational Science. "These results indicate that an abstract sense of group membership, and not only differences in physical appearance, can affect basic sensory-motor processing."

Past research has shown that race or physical similarity can influence brain processes, and we tend to have more empathy for people who look more like us.