Science of the Spirit


Memory vs. Math: Same brain areas show inverse responses to recall and arithmetic

Anatomy of the posteromedial cortex (PMC). (A) PMC (highlighted region in purple), which forms a core node of the default mode network, is located on the medial surface of the brain. (B) The PMC is bounded ventrally by the parieto-occipital sulcus (which divides it from the cuneus); dorsally by the cingulate sulcus (cgs) and its marginal branch (mb); and extends anteriorly to approximately midcingulate level before it joins the anterior cingulate cortex. The PMC contains the PCC (areas 23a, 23b, and 23c), RSC (areas 29 and 30), medial parietal cortex (area 7m), and a transitional cortical area 31. The RSC is superficially visible as gyral cortex around areas 29 and 30; however, it extends perisplenially around the corpus callosum (cc) hidden within the callosal sulcus (cs; B and C).
Scientists have historically relied on neuroimaging - but not electrophysiological - data when studying the human default mode network (DMN), a group of brain regions with lower activity during externally-directed tasks and higher activity if tasks require internal focus. Recently, however, researchers at Stanford University School of Medicine recorded electrical activity directly from a core DMN component known as the posteromedial cortex (PMC) during both internally- and externally-directed waking states - specifically, autobiographical memory and arithmetic calculation, respectively. The data they recorded showed an inverse relationship - namely, the degree activation during memory retrieval predicted the degree of suppression during arithmetic calculation - which they say provides important anatomical and temporal details about DMN function at the neural population level.

Drs. Josef Parvizi, Brett L. Foster, and Mohammad Dastjerdi faced a range of challenges when recording intracranially from the human posteromedial cortex. "A key challenge in specifically studying the electrical activity of this region is that unlike much of the brains outer cerebral cortex, the posteromedial cortex is not superficially visible," Foster tells Medical Xpress. Rather, he illustrates, it is part of the cerebral cortex that is hidden from view, which wraps over into the middle space between the left and right brain hemispheres "like the inner walls of a glacier crevasse."

This is a two-fold problem, he continues. "Not only does this hidden location make it very difficult to record this regions electrical activity from outside the skull on the scalp - a common technique - but also, even if one gets the opportunity to record more closely from inside the skull, one still needs to access this hidden cortex within the narrow space between the two hemispheres." Importantly, the ability to do so in the human brain only arises out of a unique clinical opportunity, where neurosurgeons have diligently placed electrodes onto the cortical walls of this inter-hemispheric space to monitor epileptic seizure activity as part of surgical planning. "The findings reported in our study are all derived from this unique opportunity, which allowed for direct recordings of electrical neural activity from the posteromedial cortex."
Monkey Wrench

Trauma, Susceptibility and Manipulation: "We can implant entirely false memories"

You were abducted by aliens, you saw Bugs Bunny at Disneyland, and then you went up in a balloon. Didn't you? Laura Spinney on our remembrance of things past.

© Live Science
Alan Alda had nothing against hard-boiled eggs until last spring. Then the actor, better known as Hawkeye from M*A*S*H, paid a visit to the University of California, Irvine. In his new guise as host of a science series on American TV, he was exploring the subject of memory. The researchers showed him round, and afterwards took him for a picnic in the park. By the time he came to leave, he had developed a dislike of hard-boiled eggs based on a memory of having made himself sick on them as a child - something that never happened.

Alda was the unwitting guinea pig of Elizabeth Loftus, a UCI psychologist who has been obsessed with the subject of memory and its unreliability since Richard Nixon was sworn in as president. Early on in her research, she would invite people into her lab, show them simulated traffic accidents, feed them false information and leading questions, and find that they subsequently recalled details of the scene differently - a finding that has since been replicated hundreds of times.

More recently, she has come to believe that lab studies may underestimate people's suggestibility because, among other things, real life tends to be more emotionally arousing than simulations of it. So these days she takes her investigations outside the lab. In a study soon to be published, she and colleagues describe how a little misinformation led witnesses of a terrorist attack in Moscow in 1999 to recall seeing wounded animals nearby. Later, they were informed that there had been no animals. But before the debriefing, they even embellished the false memory with make-believe details, in one case testifying to seeing a bleeding cat lying in the dust.

"We can easily distort memories for the details of an event that you did experience," says Loftus. "And we can also go so far as to plant entirely false memories - we call them rich false memories because they are so detailed and so big."

'I'm bored!' -- Research on attention sheds light on the unengaged mind

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You're waiting in the reception area of your doctor's office. The magazines are uninteresting. The pictures on the wall are dull. The second hand on the wall clock moves so excruciatingly slowly that you're sure it must be broken. You feel depleted and irritated about being stuck in this seemingly endless moment. You want to be engaged by something - anything - when a thought, so familiar from childhood, comes to mind: "I'm bored!"

Although boredom is often seen as a trivial and temporary discomfort that can be alleviated by a simple change in circumstances, it can also be a chronic and pervasive stressor that can have significant consequences for health and well-being.

Boredom at work may cause serious accidents when safety depends on continuous vigilance, as in medical monitoring or long-haul truck driving. On a behavioral level, boredom has been linked with problems with impulse control, leading to overeating and binge eating, drug and alcohol abuse, and problem gambling. Boredom has even been associated with mortality, lending grim weight to the popular phrase "bored to death."

Learning to overcome fear is difficult for teens

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New study shows fear is hard to extinguish from the developing teenage brain, which may explain why anxiety and depression spikes during adolescence.

A new study by Weill Cornell Medical College researchers shows that adolescents' reactions to threat remain high even when the danger is no longer present. According to researchers, once a teenager's brain is triggered by a threat, the ability to suppress an emotional response to the threat is diminished which may explain the peak in anxiety and stress-related disorders during this developmental period.

The study, published Sept. 17 in the early online edition of the Proceedings of the National Academy of Sciences (PNAS), is the first to decode fear acquisition and fear "extinction learning," down to the synaptic level in the brains of mice, which mirror human neuronal networks. Also, through human and rodent experiments, the study finds that acquired fear can be difficult to extinguish in some adolescents. By contrast, the study shows that adults and children do not have the same trouble learning when a threat is no longer present.

"This is the first study to show, in an experiment, that adolescent humans have diminished fear extinction learning," says the study's lead author, Dr. Siobhan S. Pattwell, a postdoctoral fellow at the Sackler Institute for Developmental Psychobiology at Weill Cornell. "Our findings are important because they might explain why epidemiologists have found that anxiety disorders seem to spike during adolescence or just before adolescence. It is estimated that over 75 percent of adults with fear-related disorders can trace the roots of their anxiety to earlier ages."

"I'm Lovin' It": Fast-Food Logos 'Imprinted' in Children's Brains, Study Says

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Childhood obesity is a growing health concern in the public sphere, but for many of us, it also hits close to home. But while public health campaigns have singled in on parents providing children with unhealthy nutrition options and with poor examples of healthy eating, new research indicates that some of the problem may lie with fast food companies and their overly effective marketing campaigns.

A study has found that fast-food logos are branded into the minds of children from an early age.

According to the Centers for Disease Control and Prevention, childhood obesity has more than tripled over the past 30 years. And perhaps more damning, the government bureau reports that "[the] percentage of children aged 6-11 years in the United States who were obese increased from 7% in 1980 to nearly 20% in 2008. Similarly, the percentage of adolescents aged 12-19 years who were obese increased from 5% to 18% over the same period."

The study, conducted by researchers from the University of Missouri-Kansas City and the University of Kansas Medical Center, showed children 60 logos from popular food brands, like Rice Krispies and KFC and 60 logos from popular non-food brands, like BMW and FedEx. The children were aged between 10 and 14. Then, using a functional MRI scanner, which measures blood flow to different areas in the brain, they watched the brains of these children react to the different logos.

Encouraging The Public With A 'Nudge' Or 'Think'

If approached in the right way, citizens are willing to change their behaviour and do more to help themselves and others, according to research funded by the Economic and Social Research Council (ESRC). The project, carried out jointly at the universities of Manchester and Southampton, experimented with different intervention techniques which encourage citizen participation and explored people's motivations for community involvement.

The researchers focused on comparing the effectiveness of 'nudge' techniques, where people are offered incentives to change their behaviour, and 'think' techniques, which takes a planned approach where people are given information, the opportunity to discuss and debate a subject, and then opportunity to act. Overall, they found that while the nudge interventions yielded better results, these were not always sustained in the long term.

Individuals responded well to nudge techniques such as doorstep canvassing, receiving feedback on their actions and to public recognition of their contribution. For example, in a recycling experiment, there was a ten per cent increase in household recycling as a result of doorstep canvassing - a nudge technique. Unfortunately, this effect did not last and after three months the increase was just four per cent.

In another experiment people were asked to pledge used books to their local library. When the donors were told that their names would be made public, another nudge technique, donations went up by 22 per cent.

The 'think' technique experiments, though less successful, offered unexpected results. On-line debate forums where people were given information on a topic and the opportunity to discuss it resulted in modest changes in their policy positions. However, this approach failed to encourage participation among people that were not already politically engaged.

Racial Bias Revealed: The Reason Why "They All Look Alike"

Racial Bias
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We've all heard the racial phrase "they all look alike." For many individuals it is a common remark that people use to describe a different race. New research has finally revealed why many individuals have a hard time recognizing others from a different race.

In a study published in the Personality and Social Psychology Bulletin, researchers suggests if individuals of one race identify themselves as a part of the same group it can improve their memory of members of a different race.

Co-author of the new study Jay Van Bavel, of New York University, and William Cunningham, of the University of Toronto, and colleagues conducted three experiments.

"One of the most robust phenomena in social perception is the finding that people are better at remembering people from their own race. This effect - called the own-race bias - is often interpreted as the consequence of perceptual expertise, whereby people spend more time with members of their own race and therefore have difficulty differentiating members of other races," Van Bavel said.

"Instead, we show that people are better at differentiating members of their own race because they simply pay more attention to who is in their own group, regardless of their race."
Eye 1

People With Psychopathic Traits Can't Smell As Well, Study Suggests

psychopath smell
There may be a link between the cold, callous personality traits associated with psychopaths and sense of smell, according to a new study.

The research, published in the journal Chemosensory Perception, showed that people who scored high on a test of psychopathy also had more problems with being able to tell different smells apart, not to mention identifying smells.

The study included 79 adults who didn't have a criminal background. The researchers conducted a number of experiments to test their ability to smell and tell smells apart, and also had them take a test that measured their levels of psychopathic traits like callousness, manipulation, the urge to commit criminal acts, and leading an erratic lifestyle.

"Our findings provide support for the premise that deficits in the front part of the brain may be a characteristic of non-criminal psychopaths," the researchers, from Macquarie University, said in a statement. "Olfactory measures represent a potentially interesting marker for psychopathic traits, because performance expectancies are unclear in odor tests and may therefore be less susceptible to attempts to fake good or bad responses."

War causes mental illness in soldiers

One in every two cases of post-traumatic stress disorder (PTSD) in soldiers remains undiagnosed. This is the conclusion reached by a working group led by Hans-Ulrich Wittchen et al. They report their study in the current issue of Deutsches Ärzteblatt International (Dtsch Arztebl Int 2012; 109(35): 559), which is a special issue focusing on the prevalence of psychological stress in German army soldiers. In a second original article, results reported by Jens T Kowalski and colleagues show that more female soldiers contact the psychosocial support services provided by Germany's armed forces than their male colleagues (Dtsch Arztbl Int 2012; 109 (35): 559).
Magic Wand

Playground peers can predict adult personalities

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Concordia 20-year study shows childhood friends can forecast adulthood success.

Even on the playground, our friends know us better than we know ourselves. New research has revealed that your childhood peers from grade school may be able to best predict your success as an adult.

Lisa Serbin of the Department of Psychology at Concordia University and Alexa Martin-Storey, a recent Concordia graduate and a current post-doctoral student at the University of Texas - both members of the Concordia-based Centre for Research in Human Development - recently published a study online, which reveals that childhood peer evaluation of classmate personalities can more accurately predict adulthood success than self-evaluation at that age.

"This study, known as the Concordia Longitudinal Risk Project, was started in 1976 by my colleagues in the Department of Psychology, Alex Schwartzman and Jane Ledingham, who is now at the University of Ottawa" says Serbin. "Over two years, Montreal students in grades 1, 4 and 7 completed peer evaluations of their classmates and rated them in terms of aggression, likeability and social withdrawal. The students also did self-evaluations."

Over the next 20 years, these children were closely followed as researchers used the exhaustive longitudinal study to track their progress into adulthood. A follow-up survey was conducted between 1999 and 2003 with nearly 700 of the participants from the initial study. The survey included measurement of adult personality traits, such as levels of neuroticism, extroversion, openness, agreeableness and conscientiousness.