Push-ups, crunches, gyms, personal trainers – people have many strategies for building bigger muscles and stronger bones. But what can one do to build a bigger brain?

Meditate.

That’s the finding from a group of researchers at UCLA who used high-resolution magnetic resonance imaging (MRI) to scan the brains of people who meditate. In a study published in the journal NeuroImage and currently available online (by subscription), the researchers report that certain regions in the brains of long-term meditators were larger than in a similar control group.

Specifically, meditators showed significantly larger volumes of the hippocampus and areas within the orbito-frontal cortex, the thalamus and the inferior temporal gyrus – all regions known for regulating emotions.

“We know that people who consistently meditate have a singular ability to cultivate positive emotions, retain emotional stability and engage in mindful behavior,” said Eileen Luders, lead author and a postdoctoral research fellow at the UCLA Laboratory of Neuro Imaging. “The observed differences in brain anatomy might give us a clue why meditators have these exceptional abilities.”

Research has confirmed the beneficial aspects of meditation. In addition to having better focus and control over their emotions, many people who meditate regularly have reduced levels of stress and bolstered immune systems. But less is known about the link between meditation and brain structure.

In the study, Luders and her colleagues examined 44 people – 22 control subjects and 22 who had practiced various forms of meditation, including Zazen, Samatha and Vipassana, among others. The amount of time they had practiced ranged from five to 46 years, with an average of 24 years.

More than half of all the meditators said that deep concentration was an essential part of their practice, and most meditated between 10 and 90 minutes every day.

The researchers used a high-resolution, three-dimensional form of MRI and two different approaches to measure differences in brain structure. One approach automatically divides the brain into several regions of interest, allowing researchers to compare the size of certain brain structures. The other segments the brain into different tissue types, allowing researchers to compare the amount of gray matter within specific regions of the brain.

The researchers found significantly larger cerebral measurements in meditators compared with controls, including larger volumes of the right hippocampus and increased gray matter in the right orbito-frontal cortex, the right thalamus and the left inferior temporal lobe. There were no regions where controls had significantly larger volumes or more gray matter than meditators.

Because these areas of the brain are closely linked to emotion, Luders said, “these might be the neuronal underpinnings that give meditators’ the outstanding ability to regulate their emotions and allow for well-adjusted responses to whatever life throws their way.”

What’s not known, she said, and will require further study, are what the specific correlates are on a microscopic level – that is, whether it’s an increased number of neurons, the larger size of the neurons or a particular “wiring” pattern meditators may develop that other people don’t.

Because this was not a longitudinal study – which would have tracked meditators from the time they began meditating onward – it’s possible that the meditators already had more regional gray matter and volume in specific areas; that may have attracted them to meditation in the first place, Luders said.

However, she also noted that numerous previous studies have pointed to the brain’s remarkable plasticity and how environmental enrichment has been shown to change brain structure.

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Other authors of the study included Arthur Toga, director of UCLA Laboratory of Neuro Imaging; Natasha Lepore of UCLA; and Christian Gaser of the University of Jena in Germany. Funding for the study was provided by the National Institutes of Health. The authors report no conflicts of interest.

The UCLA Laboratory of Neuro Imaging, which seeks to improve understanding of the brain in health and disease, is a leader in the development of advanced computational algorithms and scientific approaches for the comprehensive and quantitative mapping of brain structure and function. The laboratory is part of the UCLA Department of Neurology, which encompasses more than a dozen research, clinical and teaching programs. The department has ranked No. 1 among its peers nationwide in National Institutes of Health funding for the last seven years (2002-08).

Reposted from University of California – Los Angeles

Future mandates, however, might be better served by taking into account findings from a University of Illinois study suggesting the academic benefits of physical education classes, recess periods and after-school exercise programs. The research, led by Charles Hillman, a professor of kinesiology and community health and the director of the Neurocognitive Kinesiology Laboratory at Illinois, suggests that physical activity may increase students’ cognitive control – or ability to pay attention – and also result in better performance on academic achievement tests.

“The goal of the study was to see if a single acute bout of moderate
exercise – walking – was beneficial for cognitive function in a period of time afterward,” Hillman said. “This question has been asked before by our lab and others, in young adults and older adults, but it’s never been asked in children. That’s why it’s an important question.”

For each of three testing criteria, researchers noted a positive outcome linking physical activity, attention and academic achievement.

Study participants were 9-year-olds (eight girls, 12 boys) who performed a series of stimulus-discrimination tests known as flanker tasks, to assess their inhibitory control.

On one day, students were tested following a 20-minute resting period; on another day, after a 20-minute session walking on a treadmill. Students were shown congruent and incongruent stimuli on a screen and asked to push a button to respond to incongruencies.  During the testing, students were outfitted with an electrode cap to measure electroencephalographic (EEG) activity.

“What we found is that following the acute bout of walking, children performed better on the flanker task,” Hillman said. “They had a higher rate of accuracy, especially when the task was more difficult. Along with that behavioral effect, we also found that there were changes in their event-related brain potentials (ERPs) – in these neuroelectric signals that are a covert measure of attentional resource allocation.”

One aspect of the neuroelectric activity of particular interest to researchers is a measure referred to as the P3 potential. Hillman said the amplitude of the potential relates to the allocation of attentional resources.

“What we found in this particular study is, following acute bouts of walking, children had a larger P3 amplitude, suggesting that they are better able to allocate attentional resources, and this effect is greater in the more difficult conditions of the flanker test, suggesting that when the environment is more noisy – visual noise in this case – kids are better able to gate out that noise and selectively attend to the correct stimulus and act upon it.”

In an effort to see how performance on such tests relates to actual classroom learning, researchers next administered an academic achievement test. The test measured performance in three areas: reading, spelling and math.

Again, the researchers noted better test results following exercise.

“And when we assessed it, the effect was largest in reading comprehension,” Hillman said. In fact, he said, “If you go by the guidelines set forth by the Wide Range Achievement Test, the increase in reading comprehension following exercise equated to approximately a full grade level.

“Thus, the exercise effect on achievement is not statistically significant, but a meaningful difference.”

Hillman said he’s not sure why the students’ performance on the spelling and math portions of the test didn’t show as much of an improvement as did reading comprehension, but suspects it may be related to design of the experiment. Students were tested on reading comprehension first, leading him to speculate that too much time may have elapsed between the physical activity and the testing period for those subjects.

“Future attempts will definitely look at the timing,” he said. Subsequent testing also will introduce other forms of physical-activity testing.

“Treadmills are great,” Hillman said. “But kids don’t walk on treadmills, so it’s not an externally valid form of exercise for most children. We currently have an ongoing project that is looking at treadmill walking at the same intensity relative to a Wii Fit game – which is a way in which kids really do exercise.”

Still, given the preliminary study’s positive outcomes on the flanker task, ERP data and academic testing, study co-author Darla Castelli believes these early findings could be used to inform useful curricular changes.

“Modifications are very easy to integrate,” Castelli said. For example, she recommends that schools make outside playground facilities accessible before and after school.

“If this is not feasible because of safety issues, then a school-wide assembly containing a brief bout of physical activity is a possible way to begin each day,” she said. “Some schools are using the Intranet or internal TV channels to broadcast physical activity sessions that can be completed in each classroom.”

Among Castelli’s other recommendations for school personnel interested in integrating physical activity into the curriculum:

• scheduling outdoor recess as a part of each school day;

• offering formal physical education 150 minutes per week at the elementary level, 225 minutes at the secondary level;

• encouraging classroom teachers to integrate physical activity into learning.

An example of how physical movement could be introduced into an actual lesson would be “when reading poetry (about nature or the change of seasons), students could act like falling leaves,” she said.

The U. of I. study appears in the current issue of the journal Neuroscience. Along with Castelli and Hillman, co-authors are U. of I. psychology professor Art Kramer and kinesiology and community health graduate student Mathew Pontifex and undergraduate Lauren Raine.Reposted from the University of Illinois at Urbana-Champaign.

ScienceDaily (Dec. 29, 2008) – Researchers at the University of Rochester have shown that the human brain-once thought to be a seriously flawed decision maker-is actually hard-wired to allow us to make the best decisions possible with the information we are given.

Neuroscientists Daniel Kahneman and Amos Tversky received a 2002 Nobel Prize for their 1979 research that argued humans rarely make rational decisions. Since then, this has become conventional wisdom among cognition researchers

Contrary to Kahnneman and Tversky’s research, Alex Pouget, associate professor of brain and cognitive sciences at the University of Rochester, has shown that people do indeed make optimal decisions-but only when their unconscious brain makes the choice.

“A lot of the early work in this field was on conscious decision making, but most of the decisions you make aren’t based on conscious reasoning,” says Pouget. “You don’t consciously decide to stop at a red light or steer around an obstacle in the road. Once we started looking at the decisions our brains make without our knowledge, we found that they almost always reach the right decision, given the information they had to work with.”

Pouget says that Kahneman’s approach was to tell a subject that there was a certain percent chance that one of two choices in a test was “right.” This meant a person had to consciously compute the percentages to get a right answer-something few people could do accurately.

Pouget has been demonstrating for years that certain aspects of human cognition are carried out with surprising accuracy. He has employed what he describes as a very simple unconscious-decision test. A series of dots appears on a computer screen, most of which are moving in random directions. A controlled number of these dots are purposely moving uniformly in the same direction, and the test subject simply has to say whether he believes those dots are moving to the left or right. The longer the subject watches the dots, the more evidence he accumulates and the more sure he becomes of the dots’ motion.

Subjects in this test performed exactly as if their brains were subconsciously gathering information before reaching a confidence threshold, which was then reported to the conscious mind as a definite, sure answer. The subjects, however, were never aware of the complex computations going on, instead they simply “realized” suddenly that the dots were moving in one direction or another. The characteristics of the underlying computation fit with Pouget’s extensive earlier work that suggested the human brain is wired naturally to perform calculations of this kind.

“We’ve been developing and strengthening this hypothesis for years-how the brain represents probability distributions,” says Pouget. “We knew the results of this kind of test fit perfectly with our ideas, but we had to devise a way to see the neurons in action. We wanted to see if, in fact, humans are really good decision makers after all, just not quite so good at doing it consciously. Kahneman explicitly told his subjects what the chances were, but we let people’s unconscious mind work it out. It’s weird, but people rarely make optimal decisions when they are told the percentages up front.”

Pouget analyzed the data from a test performed in the laboratory of Michael Shadlen, a professor of physiology and biophysics at the University of Washington. Shadlen’s team watched the activity of a pair of neurons that normally respond to the sight of things moving to the left or right. For instance, when the test consisted of a few dots moving to the right within the jumble of other random dots, the neuron coding for “rightward movement” would occasionally fire. As the test continued, the neuron would fire more and more frequently until it reached a certain threshold, triggering a flurry of activity in the brain and a response from the subject of “rightward.”

Pouget says a probabilistic decision-making system like this has several advantages. The most important is that it allows us to reach a reasonable decision in a reasonable amount of time. If we had to wait until we’re 99 percent sure before we make a decision, Pouget says, then we would waste time accumulating data unnecessarily. If we only required a 51 percent certainty, then we might reach a decision before enough data has been collected.

Another main advantage is that when we finally reach a decision, we have a sense of how certain we are of it-say, 60 percent or 90 percent-depending on where the triggering threshold has been set. Pouget is now investigating how the brain sets this threshold for each decision, since it does not appear to have the same threshold for each kind of question it encounters.

The findings are published in the Dec 26 issue of the journal Neuron.

Reprinted from ScienceDaily.

Findings could help marketers optimize advertising for the human mind

Fads have been a staple of American pop culture for decades, from spandex in the 1980s to skinny jeans today. But while going from fad to flop may seem like the result of fickle consumers, a new study suggests that this is exactly what should be expected for a highly efficient, rationally evolved animal.

The new research, led by cognitive scientist Mark Changizi of Rensselaer Polytechnic Institute, shows why direct exposure to repeated ads initially increases a consumer’s preference for promoted products, and why the most effective advertisements are the ones consumers don’t even realize they have seen.

It has long been known that repeated visual exposure to an object can affect an observer’s preference for it, initially rapidly increasing preference, and then eventually lowering preference again. This can give way to short-lived fads. But while this may seem illogical, Changizi argues that it makes perfect cognitive sense.

“A rational animal ought to prefer something in proportion to the probable payoff of acting to obtain it,” said Changizi, assistant professor of cognitive science at Rensselaer and lead author of the study, which appears in the online version of the journal Perception. “The frequency at which one is visually exposed to an object can provide evidence about this expected payoff, and our brains have evolved mechanisms that exploit this information, rationally modulating our preferences.”

A small number of visual exposures to an object typically raises the probability of acquiring the object, which enhances preference, according to Changizi.

On the other hand, Changizi says overexposure to an object provides the brain with evidence that the object is overabundant, and is likely not valuable, thereby lowering the individual’s preference for it.

“An individual’s preference for an object based on a large number of visual exposures will almost always take the shape of an inverted ‘U’, with an initial rapid rise in preference based on the enhanced probability that an object can be obtained, followed by a plateau and a gradual decrease in preference as the evidence begins to suggest that the object is overly common and thus not valuable,” Changizi said.

One of the most surprising aspects of visual exposure effects, according to Changizi, is that they are enhanced when visual exposure occurs without conscious recognition.

“This non-conscious mechanism exists because visual exposure information alone, without conscious judgment, has implications for the expected payoff of one’s actions,” Changizi said. “In many natural situations, observers potentially have both exposure schedule information and consciously accessible information about the object, in which case the predicted degree of preference modulations from visual exposure will be dampened, as the visual information is competing with the information from conscious recognition of the object and any subsequent judgment.”

These non-conscious mechanisms for rationally modulating preference are the kind animals without much of a cognitive life can engage in, and Changizi speculates that they are much more ancient.

Advertising that takes the form of apparel branded with company’s names, and products strategically placed in movies and television shows, often go unnoticed by consumers, capitalizing on our brain’s mechanisms to modulate preference based on non-conscious exposure.

Changizi’s research suggests that such advertising tactics work because they tap into our non-conscious mechanisms for optimal preferences, hijacking them for selling a company’s products. The research could hold potential for marketers interested in optimizing their advertising for the human mind, Changizi says.

Changizi conducted his research with Shinsuke Shimojo, professor of biology at the California Institute of Technology. The project was funded by a grant from the National Institutes of Health.

Reprinted from Rensselaer Polytechnic Institute.

What can retailers do to make the choice process easier?

That gorgeous sweater has your name written on it. But, those red suede pumps are calling your name too. What goes through your mind as you consider these choices? During normal economic times, you might indulge in a whole new wardrobe. But now, with considerably tighter budgets, consumers don’t have the luxury of saying “It’s the holidays — I’ll just buy both!” What happens in buyers’ brains as they consider difficult choices? What can retailers do to make the choice process easier for consumers?

Akshay Rao, a marketing professor at the University of Minnesota’s Carlson School of Management, has conducted research that shows that decision making is simplified when a consumer considers a third, less attractive option. For example, when a second, less desirable sweater is also considered in the situation above, the shopper could solve their conundrum by choosing the more attractive sweater. The less appealing sweater plays the role of a “decoy” that makes the other sweater appear more pleasing than before. “In some ways, it is quite straightforward,” said Rao. “When a consumer is faced with a choice, the presence of a relatively unattractive option improves the choice share of the most similar, better item.”

In their forthcoming Journal of Marketing Research article “Trade-off Aversion as an Explanation for the Attraction Effect: A functional Magnetic Resonance Imaging Study,” Rao and co-author William Hedgcock (University of Iowa) explain the reasons for this decoy effect. Volunteers had their brains scanned while they made choices between several sets of equally appealing options as well as choice sets that included a third, somewhat less attractive option. Overall, the presence of the extra, “just okay” possibility systematically increased preference for the better options. The fMRI scans showed that when making a choice between only two, equally preferred options; subjects tended to display irritation because of the difficulty of the choice process. The presence of the third option made the choice process easier and relatively more pleasurable.

“The technical evidence for our conclusion is quite clear, based on the imaging data,” Rao said. “When considering three options, our “buyers” displayed a decrease in activation of the amygdala, an area of the brain associated with negative emotions. Seemingly, subjects were using simple heuristics — short-cuts or decision rules — rather than a more complex evaluation process, when they were evaluating three-item choice sets.”

There are several practical implications of this research. Irrelevant alternatives are routinely encountered in a variety of settings including web-based travel and vacation markets, cable deals, cell phone plans and even newspaper circulars. In these markets, the addition of irrelevant options is a strategy that ought to reduce negative emotion. “Retailers interested in helping ease the pain of consumer decision making may introduce decoys, loss leaders, or other products similar to the ones they really want to market. It will make the focal product look more attractive,” said Rao. “Plus, a frustrated customer struggling to choose between two equally attractive options may decide not to buy anything — the introduction of a third option may be better for everyone.”

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Akshay Rao’s teaching, research, and consulting have focused on industries ranging from food and airlines to apparel and the Internet. His research and opinions have been featured in Time, The Boston Globe, The New York Times, The Wall Street Journal, NPR, CNN and other outlets. More information on Rao and a copy of the article can be found at www.carlsonschool.umn.edu/marketinginstitute/arao

The Institute for Research in Marketing is part of the Carlson School of Management at the University of Minnesota. Established in 2005, the Institute fosters innovative, rigorous research that improves the science and practice of marketing. More information can be found at www.carlsonschool.umn.edu/marketinginstitute

Reprinted from University of Minnesota.

Reforming the system will require strong medicine, tough choices

To heal our ailing health care system, we need to stop thinking like Americans. That’s the message of two articles by UCLA’s Dr. Marc Nuwer, a leading expert on national health care reform, published this week in Neurology, the journal of the American Academy of Neurology.

“Americans prize individual choice and resist limiting care,” says Nuwer, a professor of clinical neurology at the David Geffen School of Medicine at UCLA. “We believe that if doctors can treat very ill patients aggressively and keep every moment of people in the last stages of life under medical care, then they should. We choose to hold these values. Consequently, we choose to have a more expensive system than Europe or Canada.”

Consider these statistics:

• The United States boasts the world’s most expensive health care system, yet only one-sixth of Americans are insured. Medical expenditures exceed $2 trillion annually, making health care the economy’s largest sector, four times bigger than national defense.

• By 2015, the U.S. government is projected to spend $4 trillion on health care, or 20 percent of the nation’s gross domestic product.

• An aging population will boost spending. Half of Medicare costs support very sick people in their last stages of life, and experts estimate that Medicare funds will be exhausted by 2018.

• 31 percent of U.S. health care funds go toward administration. “We push a lot of paper,” Nuwer says. “We spend twice as much as Canada, which has a more streamlined health care system that demands doctors complete less paperwork.”

• 10 percent of U.S. expenses are spent on “defensive medicine” – pricey tests ordered by doctors afraid of missing anything, however unlikely. “Doctors don’t want to be accused in court of a delayed diagnosis, so they bend over backwards to find something – even if it’s a rare possibility – in order to cover themselves,” Nuwer says.

Reforming the U.S. health care system with the goal of providing universal, affordable, high-quality care will require rethinking our overall values and paying greater attention to care-related expenditures, according to Nuwer.

Part of the current problem, he says, is that doctors are oblivious to the price tags of options they’re prescribing for patients. He recommends educating physicians about the costs of care, including imaging, blood tests and specific drugs.

“Does a fancy electric wheelchair cost $500 or $50,000?” Nuwer asks. “Most doctors have no clue. We need to give physicians feedback about the dollar signs behind their orders.”

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Nuwer’s co-authors on both articles include Dr. G.L. Barkley (Henry Ford Hospital, Detroit); Dr. G.J. Esper (Emory University School of Medicine, Atlanta); Dr. P.D. Donofrio (Vanderbilt University School of Medicine, Nashville); Dr. J.P. Szaflarski (University of Cincinnati Academic Health Center); and Dr. T.R. Swift (Medical College of Georgia, Augusta).

UCLA is California’s largest university, with an enrollment of nearly 38,000 undergraduate and graduate students. The UCLA College of Letters and Science and the university’s 11 professional schools feature renowned faculty and offer more than 323 degree programs and majors. UCLA is a national and international leader in the breadth and quality of its academic, research, health care, cultural, continuing education and athletic programs. Four alumni and five faculty have been awarded the Nobel Prize. For more news, visit the UCLA Newsroom.

Reprinted from the UCLA Newsroom.

Prefrontal cortex activity in poor children resembles that of stroke victim, study finds

Berkeley — University of California, Berkeley, researchers have shown for the first time that the brains of low-income children function differently from the brains of high-income kids.

In a study recently accepted for publication in the Journal of Cognitive Neuroscience, scientists at UC Berkeley’s Helen Wills Neuroscience Institute and the School of Public Health report that normal 9- and 10-year-olds differing only in socioeconomic status have detectable differences in the response of their prefrontal cortex, the part of the brain that is critical for problem solving and creativity.

Brain function was measured by means of an electroencephalograph (EEG) – basically, a cap fitted with electrodes to measure electrical activity in the brain – like that used to assess epilepsy, sleep disorders and brain tumors.

“Kids from lower socioeconomic levels show brain physiology patterns similar to someone who actually had damage in the frontal lobe as an adult,” said Robert Knight, director of the institute and a UC Berkeley professor of psychology. “We found that kids are more likely to have a low response if they have low socioeconomic status, though not everyone who is poor has low frontal lobe response.”

Previous studies have shown a possible link between frontal lobe function and behavioral differences in children from low and high socioeconomic levels, but according to cognitive psychologist Mark Kishiyama, first author of the new paper, “those studies were only indirect measures of brain function and could not disentangle the effects of intelligence, language proficiency and other factors that tend to be associated with low socioeconomic status. Our study is the first with direct measure of brain activity where there is no issue of task complexity.”

Co-author W. Thomas Boyce, UC Berkeley professor emeritus of public health who currently is the British Columbia Leadership Chair of Child Development at the University of British Columbia (UBC), is not surprised by the results. “We know kids growing up in resource-poor environments have more trouble with the kinds of behavioral control that the prefrontal cortex is involved in regulating. But the fact that we see functional differences in prefrontal cortex response in lower socioeconomic status kids is definitive.”

Boyce, a pediatrician and developmental psychobiologist, heads a joint UC Berkeley/UBC research program called WINKS – Wellness in Kids – that looks at how the disadvantages of growing up in low socioeconomic circumstances change children’s basic neural development over the first several years of life.

“This is a wake-up call,” Knight said. “It’s not just that these kids are poor and more likely to have health problems, but they might actually not be getting full brain development from the stressful and relatively impoverished environment associated with low socioeconomic status: fewer books, less reading, fewer games, fewer visits to museums.”

Kishiyama, Knight and Boyce suspect that the brain differences can be eliminated by proper training. They are collaborating with UC Berkeley neuroscientists who use games to improve the prefrontal cortex function, and thus the reasoning ability, of school-age children.

“It’s not a life sentence,” Knight emphasized. “We think that with proper intervention and training, you could get improvement in both behavioral and physiological indices.”

Kishiyama, Knight, Boyce and their colleagues selected 26 children ages 9 and 10 from a group of children in the WINKS study. Half were from families with low incomes and half from families with high incomes. For each child, the researchers measured brain activity while he or she was engaged in a simple task: watching a sequence of triangles projected on a screen. The subjects were instructed to click a button when a slightly skewed triangle flashed on the screen.

The researchers were interested in the brain’s very early response – within as little as 200 milliseconds, or a fifth of a second – after a novel picture was flashed on the screen, such as a photo of a puppy or of Mickey and Minnie Mouse.

“An EEG allows us to measure very fast brain responses with millisecond accuracy,” Kishiyama said.

The researchers discovered a dramatic difference in the response of the prefrontal cortex not only when an unexpected image flashed on the screen, but also when children were merely watching the upright triangles waiting for a skewed triangle to appear. Those from low socioeconomic environments showed a lower response to the unexpected novel stimuli in the prefrontal cortex that was similar, Kishiyama said, to the response of people who have had a portion of their frontal lobe destroyed by a stroke.

“When paying attention to the triangles, the prefrontal cortex helps you process the visual stimuli better. And the prefrontal cortex is even more involved in detecting novelty, like the unexpected photographs,” he said. But in both cases, “the low socioeconomic kids were not detecting or processing the visual stimuli as well. They were not getting that extra boost from the prefrontal cortex.”

“These kids have no neural damage, no prenatal exposure to drugs and alcohol, no neurological damage,” Kishiyama said. “Yet, the prefrontal cortex is not functioning as efficiently as it should be. This difference may manifest itself in problem solving and school performance.”

The researchers suspect that stressful environments and cognitive impoverishment are to blame, since in animals, stress and environmental deprivation have been shown to affect the prefrontal cortex. UC Berkeley’s Marian Diamond, professor emeritus of integrative biology, showed nearly 20 years ago in rats that enrichment thickens the cerebral cortex as it improves test performance. And as Boyce noted, previous studies have shown that children from poor families hear 30 million fewer words by the time they are four than do kids from middle-class families.

“In work that we and others have done, it really looks like something as simple and easily done as talking to your kids” can boost prefrontal cortex performance, Boyce said.

“We are certainly not blaming lower socioeconomic families for not talking to their kids – there are probably a zillion reasons why that happens,” he said. “But changing developmental outcomes might involve something as accessible as helping parents to understand that it is important that kids sit down to dinner with their parents, and that over the course of that dinner it would be good for there to be a conversation and people saying things to each other.”

“The study is suggestive and a little bit frightening that environmental conditions have such a strong impact on brain development,” said Silvia Bunge, UC Berkeley assistant professor of psychology who is leading the intervention studies on prefrontal cortex development in teenagers by using functional magnetic resonance imaging (fMRI).

Boyce’s UBC colleague, Adele Diamond, showed last year that 5- and 6-year-olds with impaired executive functioning, that is, poor problem solving and reasoning abilities, can improve their academic performance with the help of special activities, including dramatic play.

Bunge hopes that, with fMRI, she can show improvements in academic performance as a result of these games, actually boosting the activity of the prefrontal cortex.

“People have tried for a long time to train reasoning, largely unsuccessfully,” Bunge said. “Our question is, ‘Can we replicate these initial findings and at the same time give kids the tools to succeed?’”

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This research is supported by grants from the National Institute of Mental Health and the National Institute of Neurological Disorders and Stroke of the National Institutes of Health.

Blunted reward response, gene may trigger overeating

AUSTIN, Texas-Obese individuals may overeat because they experience less satisfaction from eating food due to a reduced response in their brains’ reward circuitry, according to a new study by Eric Stice, psychology researcher at The University of Texas at Austin.

While eating, the body releases dopamine, a neurotransmitter in the reward centers of the brain, but Stice found obese people show less activation in the striatum relative to lean people. He also found individuals with a blunted response were more likely to show unhealthy weight gain, particularly if they had a gene associated with compromised dopamine signaling in the brain’s reward circuitry.

Stice and a team of researchers have published their findings in the Science article, “Relation Between Obesity and Blunted Striatal Response to Food is Moderated by TaqIA A1 Allele.”

Although research has revealed biological factors play a major role in causing obesity, few studies have identified factors that increase people’s risk to gain weight in the future.

With support from the National Institutes of Health, Stice led a research team-comprising clinical psychologists from the university and Oregon Research Institute and sensory scientists from the John B. Pierce Laboratory and Yale University-to explore how blunted responses in the brain relate to weight gain in young females.

“The research reveals obese people may have fewer dopamine receptors, so they overeat to compensate for this reward deficit,” Stice, who has studied eating disorders and obesity for almost two decades, said. “People with fewer D2 receptors need to take in more of a rewarding substance-such as food or drugs-to experience the same level of pleasure as other people.”

Using Functional Magnetic Resonance Imaging (fMRI), Stice’s team measured how the dorsal striatum was activated in response to the taste of a chocolate milkshake (versus a tasteless solution). The researchers also tested participants for the presence of a genetic variation linked to a lower number of dopamine D2 receptors, the Taq1A1 allele.

For one year, the researchers tracked participants’ changes in body mass index. The results revealed participants with decreased striatal activation in response to the milkshake who also had the A1 allele were more likely to gain weight over time.

“Understanding the abnormalities in activation of reward circuitry in response to eating is critical to helping people regulate their weight because dopamine serves as the primary neurotransmitter in the reward pathways of the brain,” Stice said. “Although people with decreased sensitivity of reward circuitry are at increased risk for unhealthy weight gain, identifying changes in behavior or pharmacological options could correct this reward deficit to prevent and treat obesity.”

Reprinted from University of Texas at Austin.

In an experiment carried out at the Wellcome Trust Centre for Neuroimaging at UCL (University College London), volunteers were shown a selection of images, which they had already been familiarised with. Each card had a unique probability of reward attached to it and over the course of the experiment, the volunteers would be able to work out which selection would provide the highest rewards. However, when unfamiliar images were introduced, the researchers found that volunteers were more likely to take a chance and select one of these options than continue with their familiar – and arguably safer – option.

Using fMRI scanners, which measure blood flow in the brain to highlight which areas are most active, Dr Bianca Wittmann and colleagues showed that when the subjects selected an unfamiliar option, an area of the brain known as the ventral striatum lit up, indicating that it was more active. The ventral striatum is in one of the evolutionarily primitive regions of the brain, suggesting that the process can be advantageous and will be shared by many animals.

“Seeking new and unfamiliar experiences is a fundamental behavioural tendency in humans and animals,” says Dr Wittmann. “It makes sense to try new options as they may prove advantageous in the long run. For example, a monkey who chooses to deviate from its diet of bananas, even if this involves moving to an unfamiliar part of the forest and eating a new type of food, may find its diet enriched and more nutritious.”

When we make a particular choice or carry out a particular action which turns out to be beneficial, it is rewarded by a release of neurotransmitters such as dopamine. These rewards help us learn which behaviours are preferable and advantageous and worth repeating. The ventral striatum is one of the key areas involved in processing rewards in the brain. Although the researchers cannot say definitively from the fMRI scans how novelty seeking is being rewarded, Dr Wittmann believes it is likely to be through dopamine release.

However, whilst rewarding the brain for making novel choices may prove advantageous in encouraging us to make potentially beneficial choices, it may also make us more susceptible to exploitation.

“I might have my own favourite choice of chocolate bar, but if I see a different bar repackaged, advertising its ‘new, improved flavour’, my search for novel experiences may encourage me to move away from my usual choice,” says Dr Wittmann. “This introduces the danger of being sold ‘old wine in a new skin’ and is something that marketing departments take advantage of.”

Rewarding the brain for novel choices could have a more serious side effect, argues Professor Nathaniel Daw, now at New York University, who also worked on the study.

“The novelty bonus may be useful in helping us make complex, uncertain decisions, but it clearly has a downside,” says Professor Daw. “In humans, increased novelty-seeking may play a role in gambling and drug addiction, both of which are mediated by malfunctions in dopamine release.”

Reprinted from Wellcome Trust.

UCLA psychologist Golnaz Tabibnia, and colleagues Ajay Satpute and Matthew Lieberman, used a psychological test called the “ultimatum game” to explore fairness and self-interest in the laboratory. In this particular version of the test, Person A has a pot of money, say $23, which they can divide in any way they want with Person B. All Person B can do is look at the offer and accept or reject it; there is no negotiation. If Person B rejects the offer, neither of them gets any money.

Whatever Person A offers to Person B is an unearned windfall, even if it’s a miserly $5 out of $23, so a strict utilitarian would take the money and run. But that’s not exactly what happens in the laboratory. The UCLA scientists ran the experiment so sometimes $5 was stingy and other times fair, say $5 out of a total stake of $10. The idea was to make sure the subjects were responding to the fairness of the offer, not to the amount of the windfall. When they did this, and asked the subjects to rate themselves on scales of happiness and contempt, they had some interesting findings: Even when they stood to gain exactly the same dollar amount of free money, the subjects were much happier with the fair offers and much more disdainful of deals that were lopsided and self-centered.

The psychologists wanted to know if there is something inherently rewarding about being treated decently. So, they scanned several parts of the participants’ brains while they were in the act of weighing both fair and miserly offers. Consistent with previous results, the researchers found that a region previously associated with negative emotions such as moral disgust (the anterior insula) was activated during unfair treatment.   However, interestingly, they also found that regions associated with reward (including the ventral striatum) were activated during fair treatment even though there was no additional money to be gained.

As reported in the April issue of the journal Psychological Science, a journal of the Association for Psychological Science, the brain finds self-serving behavior emotionally unpleasant, but a different bundle of neurons also finds genuine fairness uplifting. What’s more, these emotional firings occur in brain structures that are fast and automatic, so it appears that the emotional brain is overruling the more deliberate, rational mind. Faced with a conflict, the brain’s default position is to demand a fair deal.

Furthermore, when the scientists scanned the brains of those who were “swallowing their pride” for the sake of cash, the brain showed a distinctive pattern of neuronal activity. It appears that the unconscious mind can temporarily damp down the brain’s contempt response, in effect allowing the rational, utilitarian brain to rule, at least momentarily.

Psychological Science is ranked among the top 10 general psychology journals for impact by the Institute for Scientific Information.

Reprinted from the Association for Psychological Science.

Philadelphia, March 28, 2008 – Many parents are convinced that the brains of their teenage offspring are different than those of children and adults. New data confirms that this is the case. An article by Jay N. Giedd, MD, of the National Institute of Mental Health (NIMH), published in the April 2008 issue of the Journal of Adolescent Health describes how brain changes in the adolescent brain impact cognition, emotion and behavior.

Dr. Giedd reviews the results from the NIMH Longitudinal Brain Imaging Project. This study and others indicate that gray matter increases in volume until approximately the early teens and then decreases until old age. Pinning down these differences in a rigorous way had been elusive until MRI was developed, offering the capacity to provide extremely accurate quantifications of brain anatomy and physiology without the use of ionizing radiation.

Writing in the article, Dr. Giedd comments, “Adolescence is a time of substantial neurobiological and behavioral change, but the teen brain is not a broken or defective adult brain. The adaptive potential of the overproduction/selective elimination process, increased connectivity and integration of disparate brain functions, changing reward systems and frontal/limbic balance, and the accompanying behaviors of separation from family of origin, increased risk taking, and increased sensation seeking have been highly adaptive in our past and may be so in our future. These changes and the enormous plasticity of the teen brain make adolescence a time of great risk and great opportunity.”

In an accompanying editorial, Elizabeth R. McAnarney MD, Department of Pediatrics, University of Rochester Medical Center, comments, “Finally neuroscientists are able to go under the ‘…leathery membrane, surrounded by a protective moat of fluid, and completely encased in bone…’ to provide new insights into brain development. Changes in the brain during childhood and adolescent development that are being documented through exquisite imaging by Giedd and others hold the promise for the development of hypotheses about the potential origins of behaviors that we have observed clinically for years….”

“Novelty seeking/sensation seeking and risk taking,” Dr. McAnarney continues, “is the basis for considerable growth during adolescence, as well as for the seemingly reckless behavior of some adolescents. Novelty seeking/sensation seeking and risk taking are topics of growing interest as adolescent brain development is defined better and as morbidity from adolescent risk taking mounts….The implication of our growing knowledge of brain-behavior mechanisms of adolescent conditions should provide insights into the risk of particular adolescents for morbidity and mortality. Preliminary data are promising so that as we begin to understand the complexity of and specificity of each of these conditions, we shall be able to diagnose and treat conditions earlier.”

The NIMH Longitudinal Brain Imaging Project began in 1989. Participants visit the NIMH at approximately two-year intervals for brain imaging, neuropsychological and behavioral assessment and collection of DNA. As of September 2007, approximately 5000 scans from 2000 subjects have been acquired. Of these, 387 subjects, aged 3 to 27 years, have remained free of any psychopathology and serve as the models for typical brain development.

Three themes have emerged from this and other studies in this new era of adolescent neuroscience. The first is functional and structural increases in connectivity and integrative processing as distributed brain modules become more and more integrated. Using a literary metaphor, maturation would not be the addition of new letters but rather of combining earlier formed letters into words, and then words into sentences and then sentences into paragraphs.

The second is a general pattern of childhood peaks of gray matter (frontal lobe, parietal lobe, temporal lobe and occipital lobe) followed by adolescent declines. As parts of the brain are overdeveloped and then discarded, the structure of the brain becomes more refined.

The third theme is a changing balance between limbic/subcortical and frontal lobe functions that extends well into young adulthood as different cognitive and emotional systems mature at different rates. The cognitive and behavioral changes taking place during adolescence may be understood from the perspective of increased “executive” functioning, a term encompassing a broad array of abilities, including attention, response inhibition, regulation of emotion, organization and long-range planning.

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The article is “The Teen Brain: Insights from Neuroimaging” by Jay N. Giedd, MD. The editorial is “Adolescent Brain Development: Forging New Links”" by Elizabeth R. McAnarney, MD. Both appear in the Journal of Adolescent Health, Volume 42, Issue 4 (April 2008) published by Elsevier.

As reported in this week’s issue of “New Scientist” magazine, research by Rice University professor of political science John Alford indicates that what is on one’s mind about politics may be influenced by how people are wired genetically.

Alford, who has researched this topic for a number of years, and his team analyzed data from political opinions of more than 12,000 twins in the United States and supplemented it with findings from twins in Australia. Alford found that identical twins were more likely to agree on political issues than were fraternal twins. On the issue of property taxes, for example, an astounding four-fifths of identical twins shared the same opinion, while only two-thirds of fraternal twins agreed.

“What we found was that it probably is going to take more than a persuasive television ad to change someone’s mind on a certain political position or attitude,” said Alford. “Individual genes for behaviors do not exist and no one denies that humans have the capacity to act against genetic predispositions. But predictably dissimilar correlations of social and political attitudes among people with greater and lesser shared genotypes suggest that behaviors are often shaped by forces of which the person themselves are not consciously aware.”

Alford believes that political scientists are too quick to dismiss genetics; rather, he believes genetics should be studied and taught along with social-environment influences.

“It has been proven that genetics plays a role in a myriad of different human interaction and makeup,” said Alford. “Why should we exclude political beliefs and attitudes?”

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About John Alford:

Alford’s research areas include American politics, congressional elections, political behavior and biology of politics. His current research concerns the biological basis of human political and social behavior. This includes small-group experiments designed to probe regularities and variability in basic social behaviors, evolutionary explanations of behaviors and predispositions, twin studies of the genetic heritability of behavioral tendencies, and brain-imaging studies of specific areas of brain activation in political decision-making.

For more information, visit http://cohesion.rice.edu/administration/fis/report/FacultyDetail.cfm?DivID=1&DeptID=62&RiceID=687.

People from different cultures use their brains differently to solve the same visual perceptual tasks, MIT researchers and colleagues report in the first brain imaging study of its kind.

Psychological research has established that American culture, which values the individual, emphasizes the independence of objects from their contexts, while East Asian societies emphasize the collective and the contextual interdependence of objects. Behavioral studies have shown that these cultural differences can influence memory and even perception. But are they reflected in brain activity patterns?

To find out, a team led by John Gabrieli, a professor at the McGovern Institute for Brain Research at MIT, asked 10 East Asians recently arrived in the United States and 10 Americans to make quick perceptual judgments while in a functional magnetic resonance imaging (fMRI) scanner–a technology that maps blood flow changes in the brain that correspond to mental operations.

The results are reported in the January issue of Psychological Science. Gabrieli’s colleagues on the work were Trey Hedden, lead author of the paper and a research scientist at McGovern; Sarah Ketay and Arthur Aron of State University of New York at Stony Brook; and Hazel Rose Markus of Stanford University.

Subjects were shown a sequence of stimuli consisting of lines within squares and were asked to compare each stimulus with the previous one. In some trials, they judged whether the lines were the same length regardless of the surrounding squares (an absolute judgment of individual objects independent of context). In other trials, they decided whether the lines were in the same proportion to the squares, regardless of absolute size (a relative judgment of interdependent objects).

In previous behavioral studies of similar tasks, Americans were more accurate on absolute judgments, and East Asians on relative judgments. In the current study, the tasks were easy enough that there were no differences in performance between the two groups.

However, the two groups showed different patterns of brain activation when performing these tasks. Americans, when making relative judgments that are typically harder for them, activated brain regions involved in attention-demanding mental tasks. They showed much less activation of these regions when making the more culturally familiar absolute judgments. East Asians showed the opposite tendency, engaging the brain’s attention system more for absolute judgments than for relative judgments.

“We were surprised at the magnitude of the difference between the two cultural groups, and also at how widespread the engagement of the brain’s attention system became when making judgments outside the cultural comfort zone,” says Hedden.

The researchers went on to show that the effect was greater in those individuals who identified more closely with their culture. They used questionnaires of preferences and values in social relations, such as whether an individual is responsible for the failure of a family member, to gauge cultural identification. Within both groups, stronger identification with their respective cultures was associated with a stronger culture-specific pattern of brain-activation.

How do these differences come about? “Everyone uses the same attention machinery for more difficult cognitive tasks, but they are trained to use it in different ways, and it’s the culture that does the training,” Gabrieli says. “It’s fascinating that the way in which the brain responds to these simple drawings reflects, in a predictable way, how the individual thinks about independent or interdependent social relationships.”

Gabrieli is the Grover Herman Professor of Health Sciences and Technology and Brain and Cognitive Sciences, and holds an appointment at the Harvard-MIT Division of Health Sciences and Technology. This study was funded by the National Institutes of Health and supported by the McGovern Institute.

URL: http://web.mit.edu/newsoffice/2008/psychology-0111.html

In contrast, Chinese, who live in a society that encourages a collectivist attitude among its members, are much more adept at determining another person’s perspective, according to a new study.

One of the consequences of  Americans’ and other Westerners’ problems of seeing things from another person’s point of view is faltering communication, said Boaz Keysar, Professor in Psychology at the University of Chicago. 

“Many actions and words have multiple meanings. In order to sort out what a person really means, we need to gain some perspective on what he or she might be thinking and, Americans for example, who don’t have that skill very well developed, probably tend to make more errors in understanding what another person means,” Keysar said.

Keysar is co-author with University graduate student Shali Wu of “The Effect of Culture on Perspective Taking,” which discusses their research and is published in the current issue of the journal Psychological Science.

Although studies of children have shown that the ability a person to appreciate another person’s perspective is universal, not all societies encourage their members to develop the skill as they grow up.  “Members of these two cultures seem to have a fundamentally different focus in social situations,” the authors wrote of Chinese and Americans.

“Members of collectivist cultures tend to be interdependent and to have self-concepts defined in terms of relationships and social obligations,” they said. “In contrast, members of individualist cultures tend to strive for independence and have self-concepts defined in terms of their own aspirations and achievements.”

In order to study this cultural difference in interpersonal communications, the team devised a game that tested how quickly and naturally people from the two groups were able to access another person’s perspective.

They chose two groups of University of Chicago students: one consisting of 20 people from China who grew up speaking Mandarin, and another group including 20 non-Asian Americans who were all native English speakers.

The researchers tested a hypothesis that suggested interdependence would make people focus on others and away from themselves. They did that by having people from the same cultural group pair up and work together to move objects around in a grid of squares placed between them. 

In the game, one person, the “director,” would tell the other person, the “subject,” where the objects should be moved. Over some of the squares, a piece of cardboard blocked the view of the director, so the subject could clearly tell what objects the director could not see. In some cases there were two similar objects, one blocked from the director’s view and one visible to both people playing the game.

The Chinese subjects almost immediately focused on the objects the director could see and moved the correct objects. When Americans were asked to move an object and there were two similar objects on the grid, they paused and often had to work to figure out which object the director could not see before moving the correct object. Taking into account the other person’s perspective was more work for the Americans, who spent on average about twice as much time completing the moves than did the Chinese. 

Even more startling for the researchers was the frequency with which many of the Americans ignored the fact that the director could not see all the objects.

“Despite the obvious simplicity of the task, the majority of American subjects (65 percent) failed to consider the director’s pespective at least once during the experiment,” by asking the director which object he or she meant or by moving an object the director could not see, Keysar said.  In contrast, only one Chinese subject seemed confused by the directions.

“Apparently, the interdependence that pervades Chinese culture has its effect on members of the culture over time, taking advantage of the human ability to distinguish between the mind of the self and that of the other, and developing this ability to allow Chinese to unreflectively interpret the actions of another person from his or her perspective,” the authors wrote.

Americans do not lose this ability, but years of culturalization based values of independence do not promote the development of mental tools needed to take into account another person’s point of view, they said.

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