Estrogen Works in the Brain to Keep Weight in Check, Study Shows

A recent UT Southwestern Medical Center study found that estrogen regulates energy expenditure, appetite and body weight, while insufficient estrogen receptors in specific parts of the brain may lead to obesity.

"Estrogen has a profound effect on metabolism," said Dr. Deborah Clegg, associate professor of internal medicine and senior author of the study published Oct. 5 in Cell Metabolism. "We hadn't previously thought of sex hormones as being critical regulators of food intake and body weight."

The mouse study is the first to show that estrogen, acting through two hypothalamic neural centers in the brain, keeps female body weight in check by regulating hunger and energy expenditure. Female mice lacking estrogen receptor alpha -- a molecule that sends estrogen signals to neurons -- in those parts of the brain became obese and developed related diseases, such as diabetes and heart disease.

Similar results were not seen in male mice, although researchers suspect other unknown estrogen receptor sites in the brain play a similar role in regulating metabolism for males as well.

Estrogen receptors are located throughout the body, but researchers found two specific populations of estrogen receptors that appear to regulate energy balance for female mice.

The findings are potentially important for millions of postmenopausal women, many of whom have decided against hormonal replacement therapy. The study could lead to new hormonal replacement therapies in which estrogen is delivered to specific parts of the brain that regulate body weight, thereby avoiding the risks associated with full-body estrogen delivery, such as breast cancer and stroke.

Doctors stopped routinely recommending long-term estrogen therapy for menopausal women in 2002 when a Women's Health Initiative study showed the hormone also led to increased risk of cardiovascular disease.
"The role of estrogen in postmenopausal women continues to remain uncertain," Dr. Clegg said. "Current research is focused on the timing and the type of estrogen supplementation that would be most beneficial to women. Our findings further support a role for estrogens in regulating body weight and energy expenditure, suggesting a benefit of estrogen supplementation in postmenopausal women."

Other UT Southwestern researchers involved in the study included lead author Dr. Yong Xu, a former postdoctoral researcher in Dr. Clegg's lab; Dr. Carol Elias, assistant professor of internal medicine; and Dr. Joel Elmquist, professor of internal medicine.

The research was supported by grants from the National Institutes of Health, the American Heart Association and the American Diabetes Association.


Via: Sciencedaily

Pushing the Limits of Performance

Deceiving the brain can lead to an improvement of up to five per cent in sporting performance, according to research from Northumbria University -- news which could have a significant impact on athletes' chances in the 2012 Olympics.



In a research project, trained cyclists were asked to race against an avatar on a computer screen which they believed was moving at the rate of the cyclist's personal best.
However, the avatar was actually going at a speed one per cent faster than the cyclist's fastest time. Despite this, the cyclists, who could also see themselves as an avatar cycling the virtual course, were able to match their opponent, going faster than they ever had before.

Researchers believe this is because there is a reserve of energy production that can be tapped into, even in well-trained athletes.

In training, the mind anticipates the end of a bout of exercise in order to set an initial pace. Sensory receptors, which monitor the body's responses, feed this information back to the brain, allowing it to control the body's resources to last until the end of the exercise to avoid damage.

Professor Kevin Thompson, Head of Sport and Exercise Sciences at Northumbria University, who carried out the research along with PhD student Mark Stone, said: "We feel that this system is conservative and even in well-trained individuals, who have a well developed pacing template, there is a reserve of energy production which can be utilised to further enhance performance."

He added: "These findings demonstrate a metabolic reserve exists which, if it can be accessed, can release a performance improvement of between two and five per cent in terms of their average power output.
"At elite level sport, even an increase of one per cent in average speed can make the difference between somebody being placed in a race or not.''

The study found that adding a competitive opponent to motivate participants to access this reserve was not effective when the participant was aware that their opponent was exercising at a power output 2% or 5% greater, but was effective when participants did not know.

Prof Thompson added: "We believe a small deception of the brain can enhance performance. Despite the internal feedback to the brain being heightened by the extra power output being produced, the participants still believed it was possible to beat their opponent."

Vía: ScienceDaily

Brain imaging reveals why we remain optimistic in the face of reality

For some people, the glass is always half full. Even when a football fan's team has lost ten matches in a row, he might still be convinced his team can reverse its run of bad luck. So why, in the face of clear evidence to suggest to the contrary, do some people remain so optimistic about the future?

In a study published today in Nature Neuroscience, researchers at the Wellcome Trust Centre for Neuroimaging at UCL (University College London) show that people who are very optimistic about the outcome of events tend to learn only from information that reinforces their rose-tinted view of the world. This is related to 'faulty' function of their frontal lobes.

People's predictions of the future are often unrealistically optimistic. A problem that has puzzled scientists for decades is why human optimism is so pervasive, when reality continuously confronts us with information that challenges these biased beliefs.

"Seeing the glass as half full rather than half empty can be a positive thing – it can lower stress and anxiety and be good for our health and well-being," explains Dr Tali Sharot. "But it can also mean that we are less likely to take precautionary action, such as practising safe sex or saving for retirement. So why don't we learn from cautionary information?"

In this new study, Dr Sharot and Professor Ray Dolan from the Wellcome Trust Centre for Neuroimaging, together with Christoph Korn from the Berlin School of Mind and Brain have shown that our failure to alter optimistic predictions when presented with conflicting information is due to errors in how we process the information in our brains.

Nineteen volunteers were presented with a series of negative life events, such as car theft or Parkinson's disease, whilst lying in a functional magnetic resonance imaging (fMRI) scanner, which measures activity in the brain. They were asked to estimate the probability that this event would happen to them in the future. After a short pause, the volunteers were told the average probability of this event to occur. In total, the participants saw eighty such events.

After the scanning sessions, the participants were asked once again to estimate the probability of each event occurring to them. They were also asked to fill in a questionnaire measuring their level of optimism.
The researchers found that people did, in fact, update their estimates based on the information given, but only if the information was better than expected. For example if they had predicted that their likelihood of suffering from cancer was 40%, but the average likelihood was 30%, they might adjust their estimate to 32%. If the information was worse than expected – for example, if they had estimated 10% – then they tended to adjust their estimate much less, as if ignoring the data.

The results of the brain scans suggested why this might be the case. All participants showed increased activity in the frontal lobes of the brain when the information given was better than expected, this activity actively processed the information to recalculate an estimate. However, when the information was worse than estimated, the more optimistic a participant was (according to the personality questionnaire), the less efficiently activity in these frontal regions coded for it, suggesting they were disregarding the evidence presented to them.

Dr Sharot adds: "Our study suggests that we pick and choose the information that we listen to. The more optimistic we are, the less likely we are to be influenced by negative information about the future. This can have benefits for our mental health, but there are obvious downsides. Many experts believe the financial crisis in 2008 was precipitated by analysts overestimating the performance of their assets even in the face of clear evidence to the contrary."

'Understanding the brain' is one of the Wellcome Trust's key strategic challenges. At the Wellcome Trust Centre for Neuroimaging, clinicians and scientists study higher cognitive function to understand how thought and perception arise from brain activity, and how such processes break down in neurological and psychiatric disease.

Commenting on the study, Dr John Williams, Head of Neuroscience and Mental Health at the Wellcome Trust, said: "Being optimistic must clearly have some benefits, but is it always helpful and why do some people have a less rosy outlook on life? Understanding how some people always manage to remain optimistic could provide useful insights into happens when our brains do not function properly."

###

The research was funded by the Wellcome Trust, the British Academy and the German Academic Exchange Service.

Via:
http://www.eurekalert.org/pub_releases/2011-10/wt-bir100611.php

How Your Brain Reacts To Mistakes Depends On Your Mindset

“Whether you think you can or think you can’t—you’re right,” said Henry Ford. A new study, to be published in an upcoming issue of Psychological Science, a journal of the Association for Psychological Science, finds that people who think they can learn from their mistakes have a different brain reaction to mistakes than people who think intelligence is fixed.


“One big difference between people who think intelligence is malleable and those who think intelligence is fixed is how they respond to mistakes,” says Jason S. Moser, of Michigan State University, who collaborated on the new study with Hans S. Schroder, Carrie Heeter, Tim P. Moran, and Yu-Hao Lee. Studies have found that people who think intelligence is malleable say things like, “When the going gets tough, I put in more effort” or “If I make a mistake, I try to learn and figure it out.” On the other hand, people who think that they can’t get smarter will not take opportunities to learn from their mistakes. This can be a problem in school, for example; a student who thinks her intelligence is fixed will think it’s not worth bothering to try harder after she fails a test.

For this study, Moser and his colleagues gave participants a task that is easy to make a mistake on. They were supposed to identify the middle letter of a five-letter series like “MMMMM” or “NNMNN.” Sometimes the middle letter was the same as the other four, and sometimes it was different. “It’s pretty simple, doing the same thing over and over, but the mind can’t help it; it just kind of zones out from time to time,” Moser says. That’s when people make mistakes—and they notice it immediately, and feel stupid.

While doing the task, the participant wore a cap on his or her head that records electrical activity in the brain. When someone makes a mistake, their brain makes two quick signals: an initial response that indicates something has gone awry—Moser calls it the “’oh crap’ response”—and a second that indicates the person is consciously aware of the mistake and is trying to right the wrong. Both signals occur within a quarter of a second of the mistake. After the experiment, the researchers found out whether people believed they could learn from their mistakes or not.




People who think they can learn from their mistakes did better after making a mistake – in other words, they successfully bounced back after an error. Their brains also reacted differently, producing a bigger second signal, the one that says “I see that I’ve made a mistake, so I should pay more attention” Moser says.

The research shows that these people are different on a fundamental level, Moser says. “This might help us understand why exactly the two types of individuals show different behaviors after mistakes.” People who think they can learn from their mistakes have brains that are tuned to pay more attention to mistakes, he says. This research could help in training people to believe that they can work harder and learn more, by showing how their brain is reacting to mistakes.

###

For more information about this study, please contact: Jason S. Moser at jmoser@msu.edu.

via: http://www.psychologicalscience.org

National Geographic: Teenage Brains

Moody. Impulsive. Maddening. Why do teenagers act the way they do? Viewed through the eyes of evolution, their most exasperating traits may be the key to success as adults.

 

See the rest of the note by clicking the link below:
http://ngm.nationalgeographic.com/2011/10/teenage-brains/dobbs-text/1

 

Brain rhythms are key to learning

New study from MIT neuroscientists finds that brain waves shift frequency as a new task becomes routine.

Neuroscientists have long known of the existence of brain waves — rhythmic fluctuations of electrical activity believed to reflect the brain’s state. For example, during rest, brain activity slows down to an alpha rhythm of about eight to 10 hertz, or cycles per second.

It has been unclear what role, if any, these waves play in cognitive functions such as learning and memory. But now, a study from MIT neuroscientists shows that a switch between two of these rhythms is critical for learning habitual behavior.

In a paper appearing this week in the Proceedings of the National Academy of Sciences (PNAS), the researchers report that as rats learn to run a maze, activity in a brain region that controls habit formation shifts from a fast, chaotic rhythm to a slower, more synchronized pace. That switch, which occurs just as the rats start to master the maze, likely signals that a habit has been formed, says MIT Institute Professor Ann Graybiel, senior author of the PNAS paper.

This is a major clue to how the brain reorganizes itself during learning, says Graybiel, who is also a principal investigator at the McGovern Institute for Brain Research at MIT.

Rhythms in the brain

Several brain waves of different frequencies have been observed in humans and other animals. This paper focused on beta waves, which range from 15 to 28 hertz, and high gamma waves, which range from 70 to 90 hertz. The beta band is associated with a lack of movement, and gamma with highly attentive states.

Graybiel and graduate student Mark Howe, lead author of the paper, set out to see if they could link these rhythms with the changes in brain state that accompany learning.

Graybiel’s lab has previously shown that patterns of electrical activity in a part of the brain known as the basal ganglia are critical for habit formation. Habits begin when you gain some benefit for taking a particular action, but eventually the behavior becomes ingrained and you do it even when you no longer get the reward. In extreme cases, this could mean continuing to scratch part of the body even after it stops itching, for example.

In this study, Howe looked at brain rhythms in a region at the very bottom of the basal ganglia, known as the ventral striatum. This area is necessary for responding to pain or pleasure, and is also highly involved in addiction.

Brain activity was measured as rats ran along a T-shaped maze, in which they had to learn to turn left or right in response to a sound. If they made the correct turn and reached the end of the maze, they received a reward: chocolate milk.

In the first few runs, while the rats were still learning the maze, the researchers saw bursts of ventral striatum activity in the gamma frequency range shortly before the rats finished the maze. This activity was dispersed throughout the ventral striatum: Cells synchronized with the rhythm at different times, in a fairly uncoordinated fashion.

When the rats began to catch on to how to earn the reward, the gamma activity faded away and was replaced with short bursts of activity in the beta band, a lower frequency, just after they finished the maze. The activity also became much more coordinated throughout the entire ventral striatum.

“Although there has been a lot of work on studying brain oscillations, there’s really no work looking at how oscillations in different frequency bands impact different parts of the learning process, and that’s what this paper does,” says Michael Frank, an associate professor of cognitive, linguistic and psychological sciences at Brown University who was not involved with the work.

Reinforcing habits

To get a deeper view of what was happening during this frequency shift, the researchers also measured activity from single neurons in the ventral striatum, and found that activity in two groups of neurons coordinated with the oscillations. Output neurons, which control the ventral striatum’s communication with the rest of the brain, spiked during the peaks of both gamma and beta oscillations. Another type, which inhibits the output neurons, spiked at the troughs of the oscillations.

“Whenever you have a strong rhythm, these two populations of neurons oscillate in opposite directions,” Howe says.

This finding suggests that while the rats are learning a new behavior, the high-frequency activity in the output neurons of the ventral striatum sends messages to the rest of the brain directing it to learn a new behavior, reinforced by the chocolate reward. Then, once the behavior is learned and a habit is formed, those messages are no longer needed, and are shut off by inhibitory neurons during the beta oscillations.

“As the rats were learning, that reinforcement signal goes away, because you really don’t need it,” Graybiel says. This is beneficial to the brain because once that habit is formed, “what you want to do is free up that bit of brain so you can do something else — form a new habit or think a great thought,” she says.

The researchers, including Howe, Graybiel, and other lab members Hisham Attalah, Dan Gibson and Andrew McCool, are now planning to investigate whether habit formation is interrupted if they alter the brain rhythms in the ventral striatum. They also want to identify more specifically the neurons that are involved. Identifying and controlling such neurons might offer a new way to help combat addiction — an extreme form of habitual behavior.


To see the original articule, please click the link below:
http://web.mit.edu/newsoffice/2011/habit-formation-0927.html

Zen Brain: Exploring The Connection Between Neuroscience And Meditation

This past August, more than 50 people gathered in the Circle of the Way temple at Upaya Zen Center in Santa Fe, New Mexico, to explore the connection between neuroscience and meditation. This is the fourth year we have done so.

Why? This is a Zen center that is inspired by the example set by His Holiness the Dalai Lama, who nearly 30 years ago began a dialogue with Dr. Francisco Varela and myself that was to eventually become embodied in the Mind & Life Institute, an organization that supports and sustains dialogue and rigorous scientific inquiry into meditative states.

Over the years His Holiness has enjoyed relationships with many scientists, including Varela, Sir Karl Popper, and David Bohm. His Holiness said:

With the ever growing impact of science on our lives, religion and spirituality have a greater role to play reminding us of our humanity. There is no contradiction between the two. Each gives us valuable insights into the other. Both science and the teachings of the Buddha tell us of the fundamental unity of all things.

Upaya Zen Center continues this deep inquiry into science and Buddhism through the vehicle of the Zen Brain retreats, as well as other programs. Those who are enrolled in Upaya's Contemplative End-of-Life Care training (for medical professionals) and the Buddhist Chaplaincy Program develop a thorough grounding in the latest findings on neuroscience and meditation as they go about their work in the world.

In the Zen Brain retreats, prominent scientists and Zen practitioners explore Buddhist, neuro-scientific and clinical science perspectives on topics like altruism, compassion and consciousness. Lectures and discussions with participants are embedded within zazen (meditation) practice throughout each day.

The most recent Zen Brain program this August explored trauma, stress, loss and the human potential for resilience and happiness. The faculty, drawn from the most accomplished clinicians and researchers studying this topic, featured Al Kaszniak, Ph.D., George Chrousos, M.D., George A. Bonanno, Ph.D. and Philippe Goldin, Ph.D. I also had the privilege of participating with these scientists as a contemplative and someone who has worked in this field for many years.

The main coordinator of this unusual program at Upaya is Dr. Kaszniak, the director of the Neuropsychology, Emotion and Memory Lab at the University of Arizona, where he studies Alzheimer's disease and other age-related neurological disorders, as well as emotion response and regulation in long-term Zen and mindfulness meditators. His most recent publication is a chapter on the use of meditation to reduce stress and improve well-being among caregivers of persons with dementia to be included in the book Enhancing Cognitive Fitness in Adults: A Guide to the Use and Development of Community-Based Programs (P.E. Hartman-Stein and A. LaRue, eds.).

Dr. Chrousos is renowned as one of the world's pre-eminent pediatric physicians and endocrinologists. He also serves as the UNESCO chair in adolescent care. His expertise in stress in large part can be linked to his work in endocrinology. Dr. Chrousos' presentation during Zen Brain on "Stress: the Good, the Bad, and the Ugly" explored the effects of stress on the individual.

Dr. Bonanno, professor of clinical psychology at Columbia University, has been hailed as a pioneering researcher in bereavement and trauma. In work funded by the National Institutes of Health and the National Science Foundation, Dr. Bonanno has examined how adults and children respond to and cope with extremely aversive events, such as the death of a loved one, war, sexual abuse, and terrorist attack. More recently, he has focused on defining psychological resilience in adults exposed to extreme adversity and on the factors that might inform resilient outcomes.

Dr. Goldin is a postdoctoral researcher in the Department of Psychology at Stanford University. His clinical research focuses on the effect of mindfulness meditation and cognitive behavioral therapy on neural substrates of emotional reactivity, emotion regulation, and attention regulation. He also explores the effect of child-parent mindfulness meditation training on anxiety, compassion, and quality of family interactions.

Buddhism is a path to liberation from suffering, and among the most pervasive universal triggers of suffering are trauma, stress and loss, including bereavement. Fundamental to Buddhist teaching is the recognition that freedom from suffering can be found through realizing that the fundamental nature of our mental experience is ever-changing, interdependent and without any fixed, unchanging self at its core.

In these unusual programs, participants explore constructs like "affective stickiness," a phrase coined by Dr. Richard Davidson, Research Professor of Psychology and Psychiatry at the University of Wisconsin-Madison. This is the phenomenon by which we interpret an experience as negative and then become so strongly identified with it that it becomes a fixed part of "us." The particular kind of misinterpreation of self-identification can prevent us from accessing our full range of consciousness and often limits our capacity to make choices regarding a situation.
This phenomenon recalls the astute observation that Albert Einstein made in 1950:

A human being is a part of a whole, called by us 'universe,' a part limited in time and space. He experiences himself, his thoughts and feelings as something separated from the rest... a kind of optical delusion of his consciousness. This delusion is a kind of prison for us, restricting us to our personal desires and to affection for a few persons nearest to us. Our task must be to free ourselves from this prison by widening our circle of compassion to embrace all living creatures and the whole of nature in its beauty.

What would it mean for us to truly understand that this thing we call "self" is a fiction, not only from a philosophical perspective but from a scientific one? What kind of impact could that realization have on the way we structure our economy, our health care system, our government, and even our relationships with each other, with those "different" from us, and with the Earth?
What a marvelous possibility for us to explore at this time in our planet's history.

If you'd like to join us in this exploration, the next Zen Brain program is January 12-15, 2012. More information is available on the Upaya website, www.upaya.org.

Vía: huffington post

Prenatal Exposure to Stress Linked to Accelerated Cell Aging

Young adults whose mothers experienced psychological trauma during their pregnancies show signs of accelerated aging, a UC Irvine-led study found.

The researchers discovered that this prenatal exposure to stress affected the development of chromosome regions that control cell aging processes. The study results, which appear online this week in the Proceedings of the National Academy of Sciences, point to the importance of maternal health and well-being during pregnancy.

"Our previous research on prenatal stress exposure has shown its effects on long-term metabolic, immune, endocrine and cognitive function," said the paper's lead author, Dr. Pathik D. Wadhwa, UCI professor of psychiatry & human behavior, obstetrics & gynecology, pediatrics, and epidemiology. "But this is the first to show the impact of prenatal stress on cell aging in humans, and it sheds light on an important biological pathway underlying the developmental origins of adult disease risk."

Study participants were healthy 25-year-old women and men born to mothers who had, during pregnancy, experienced psychosocial stress in the form of major, traumatic life events, such as the death or sudden severe illness of an immediate family member. Blood tests revealed that subjects' white blood cells had aged an average of three and a half more years -- five among women -- than those of individuals whose mothers had uneventful pregnancies.

This hastened aging was evidenced by the shortened length of telomeres, repetitive stretches of DNA-protein complexes that cap and protect the ends of chromosomes. Telomeres maintain chromosomal stability and control the processes that underlie cellular aging by functioning as a "clock" that regulates how many times a cell can divide. The shorter the telomere strands, the faster the cell ages.

The telomere maintenance system plays an important role in human disease and longevity, and scientists now know that telomere length is correlated to the risk of disease and premature mortality in humans. Truncated telomeres -- such as those found in the white blood cells of study participants -- can, for example, be a precursor to diabetes, cancer and coronary heart disease.

"These results indicate that stress exposure in intrauterine life is a significant predictor of adult telomere length -- even after accounting for other established prenatal and postnatal influences on telomere length," said Sonja Entringer, UCI assistant professor of pediatrics and first author on the paper.
A rapidly emerging body of human and animal research indicates that intrauterine conditions play an important role not only in all aspects of fetal development and health across gestation and birth, but also in a wide range of physical and mental health outcomes over an individual's entire lifespan.

Elizabeth H. Blackburn, Elissa S. Epel and Jue Lin of UC San Francisco and German researchers Robert Kumsta, Dirk H. Hellhammer and Stefan Wust contributed to the study, which was supported by the National Institutes of Health and the Barney & Barbro Fund.

Via: ScienceDaily

How your brain works

In this series of videos, you will see how your brain works





These brief videos provide an introductory appreciation of how we learn skills and information, move, think, feel, speak and remember. They are brought to you by the UCLA Brain Research Institute and by Bruce H. Dobkin, MD, who directs the neurorehabilitation program in the Department of Neurology at UCLA. The videos especially aim to reach out to students in grade school to stir their interest, and to people with disabilities in walking, using an affected upper extremity, and loss of memory from neurological diseases such as stroke, brain trauma, tumors, multiple sclerosis, cerebral palsy, Parkinsons, and Alzheimers disease.

Video 1:
General organization of a real human brain.

Video 2:
The pathology of brain injuries and diseases. Rat versus human brain complexity. How do we reach for a ball? How do we walk?

Video 3:
How does practice enable us to learn and retain skills and information?

Video 4:
How can we drive the nervous system to adapt in ways that help restore lost skills after injury from disease? Can we reorganize the brains connections?

Specific Brain Area Found Responsive for Rewards

According to researchers from the Centre de Neuroscience Cognitive (Cognitive Neuroscience Center) in Lyon, France, the orbitofrontal cortex, which is located in the anterior ventral part of the brain, is comprised of distinct regions that respond to rewards like money and chocolate.

Every day we must make reward choices. In order to do so, we have to compare their value on a single scale, which hints that all rewards are assessed in the same area. However, at the same time it is possible that different rewards activate different brain areas, depending on the characteristics of the reward.
To study the brain areas associated with rewards, scientists conducted a game as an experiment. Participants were rewarded with money and their cerebral activity was measured with an FMRI (functional magnetic resonance imaging) scanner.

The experiment concluded that reward association is shared between the cerebral regions known as the ventral striatum, insula, mesencephalon and the anterior cingulated cortex. Scientists also found that there is dissociation between primary and secondary awards, which supports the hypothesis of different brain areas responding to various gratifications.

How Golf Practice Changes the Brain

Neuroscience research provides increased understanding of how behavior and specific activities change the brain.  This type of research underscores the concept of neuroplasticity--that our brains change in response to how it is used on a daily basis.

One area of research in neuroplasticity is the effect of specific cognitive and motor behavior on brain structure.  A novel study published in The Journal of Neuroscience examined the effect of golf practice on brain structure.  Bezzola and colleagues from Switzerland and Germany in this study proposed that golf practice is likely to effect the following brain regions based on their known functions:

• Dorsal stream--development of visuomotor skills
• Subcortical and cerebellar regions--motor learning
• Frontal association areas--cognitive aspects of skill development

A group of relatively novice golfers had brain scan before and after a period of 40 hours of golf practice.  This study used a real world type of design.  The golfer intervention group were directed to complete their practice under a golf instructor at their own course at their own pace.  The experimental group and control groups in this study were between the ages of 40 and 60 years of age as the goal was to examine the effect in those who were likely to begin experiencing some decline in brain cognitive function.

The brain imaging in this study was completed using magnetic resonance imaging or MRI.  This technique allows for examination of small changes in brain gray and white matter volumes.

The golf practice intervention group demonstrated significant brain volume increases in a variety of brain regions including the:

• ventral premotor cortex
• several regions in the parietal cortex including the inferior parietal cortex (area demonstrated in the attached Brain Tutor HD screen shot)
• parietal-occipital junction

The golfers in the study took up to five months to complete the 40 hours of practice.  Interestingly, those who completed their practice in the least number of days showed the greatest increase in brain volumes in at the parietal occipital junction.

The authors note their study is important because it shows brain neuroplasticity occurs not just in strictly controlled motor exercise protocols but in the real world of structured leisure activity like golf.  The note structured leisure exercise activities "may be considered an additional therapeutic setting in the process of neuro-rehabilitation.

This study also suggests middle-aged individuals have a new excuse for taking up a new physical activity like golf.  If their spouse objects to heading out to the golf course to practice, a scientific response might be: "Honey, I'm just going out to work out my brain parietal-occipital junction".

Via: BrainPost

The Bilingual Brain

A new study sheds further light on how we learn language, showing the power of early exposure to language. Language is something that humans are very good at, which is a way of saying that we have cortex dedicated to and specialized for language.

The dominant hemisphere (dominant by definition, the left hemisphere in most people) contains several structures specialized for language. Wernicke’s area is the brain’s dictionary – it translates words into concepts and concepts into words. When you are trying to think of a specific word for something – that process is taking place in Wernicke’s area. There is also specialized cortex that processes auditory information, translating sounds into words, and feeding that information to Wernicke’s area. In the frontal lobe there is Broca’s area that converts words into speech – essentially this is specialized motor cortex that allows for the exquisite control of the muscles of speech necessary to produce the subtle sounds of speech. Wernicke’s area and Broca’s area are connected by a cable called the arcuate fasciculus.

It has also been known for a long time that the language cortex develops when we are very young, beginning in infancy and then pretty much locking in place by the time we are four years old. This is the “window” of development for language. For children who are raised without exposure to language by age four, they will never acquire normal fluency. If you normally developed a primary language, and then learn a second language after age four, the second language will use more brain resources – it won’t have the same language cortex encoding that the primary language does.

This window of development also applies to phonemes – the individual sounds that make up words. We learn a finite number of phonemes by age four, and then we are pretty much stuck with that set of language sounds. Children as young as 8-10 months old start to learn how to distinguish sounds that are part of speech from other sounds, and the speech sounds (phonemes) become encoded in the language cortex. After about four years old no new phonemes can be learned, and every speech sound we hear from that point forward will be slotted into an existing phoneme.

This is where the new study comes in. The researchers found that babies 8-10 months old were already developing the ability to distinguish sounds important to language – like the difference between an “r” and an “l” in English. However, they also found that babies not exposed to a language that makes this distinction, for example like a child raised in a Japanese household, will start to lose the ability to make this distinction at the same age. So by 10 month old children are already losing their ability to learn new languages, or at least the sounds that make up languages.

In addition they found that children raised in a bilingual household had a greater facility for learning language and the window of learning new sounds was extended. The researchers hypothesize that in a bilingual environment children learn that there is more than one word for everything, and they also greatly stimulate their language cortex by the task of switching between the two languages.

This study extends what was already known about the advantages of learning multiple languages by age four. This study, in fact, indicates that if you want to maximize your child’s language ability, they should be exposed to a second language from infancy.

The study looked at children raised in a bilingual household. It is unclear if the advantage extend to simply playing a second language for the children to hear, but that is not being used interactively with another person. Perhaps a video would be better than pure audio, but still that should be studied specifically before any claims are made for such products. Children may need direct human interaction to make the connection with language.

This study does add to existing evidence, and suggests that perhaps parents should be encouraged to expose children to more than one language. Language instruction might also be added to preschool and daycare programs. By the time children reach Kindergarten, it’s already too late.

via: Neurologicablog

Interactive Human Brain in 3D

Very interesting 3D Brain.

http://www.healthline.com/human-body-maps/brain#3/4294967273

Enjoy it!

But, just in case you don´t realise, please, consider to see and watch the whole 3D body  animation.
And I also recomend you to watch this youtube video:

Do you know what a MEG (magnetoencephalography) is?

A Magnetoencephalography (MEG) is a technique for mapping brain activity by recording magnetic fields produced by electrical currents occurring naturally in the brain, using arrays of SQUIDs (superconducting quantum interference devices). Applications of MEG include basic research into perceptual and cognitive brain processes, localizing regions affected by pathology before surgical removal, determining the function of various parts of the brain, and neurofeedback.

Here, you will find a full explanation of what a MEG is.
http://en.wikipedia.org/wiki/Magnetoencephalography




And also an instructive video:

 

The Brain’s Working-Memory Capacity Revealed

A new study provides a deeper look into why most people’s brains have a limited capacity to memorize information. The knowledge gained in the paper, which was published in last week’s issue of the Proceedings of the National Academy of Science, could help hone cognition-boosting games and visual displays for airplane pilots and automobile drivers.

One of the more basic limitations of our intelligence is the maximum number of information pieces the brain can memorize and retrieve on a short-term basis. This is known as the maximum capacity of the working memory.

                                                    

A team from the Massachusetts Institute of Technology (MIT) in Cambridge, Mass., tested the working-memory capacity of two macaque monkeys. The researchers were not surprised to find that four is the maximum number of objects the macaques could remember information about at any given time. That’s the same maximum capacity of most people’s working memory, according to earlier studies.

(Monkey's Can Recall Simple Shapes)

But the MIT team members did not expect their major finding, which was that the left and right visual fields—and hence the right and left hemispheres of the brain where information from each field, respectively, is processed—seem to be independent. Neural recordings uncovered the fact that the monkeys were limited to recalling two objects in their right and left visual fields.

“Before the study, we expected that information resources in your brain could be used in a very flexible way —that one hemisphere can lend a hand when the other hemisphere is only using part of its capacity,” explained lead researcher Timothy Buschman, PhD. “But it seems that’s not the case. There are limitations—although we don’t yet know whether these are physical or something else—to how information from the outside world can be represented internally in the brain and hence remembered, accessed and utilized.”

Dr. Buschman is a postdoctoral associate at the Picower Institute for Learning and Memory in the Department of Brain and Cognitive Sciences at MIT. He, along with his supervisor and institute associate director Earl Miller, Ph.D, and two other researchers simultaneously recorded the firing of neurons in the prefrontal and parietal cortices of the brains of the two macaques. The monkeys watched a computer screen that displayed very briefly, either two, three, four, or five coloured squares. A short time later the monkeys were shown the same display but with one square coloured differently. The macaques received a reward for glancing toward the single changed square.

Each monkey could only remember information regarding an average of four coloured squares. In addition, the neural recordings showed that the monkeys could only recall two objects on each side of their field of vision. The limitation occurred during memory encoding, not during memory retrieval.

“Why our working memory has a limited capacity has been the subject of an ongoing debate among researchers,” said Dr. Buschman. “One group believes it’s because there only a limited number of objects we can hold in our mind at one time. Other people think we have a pool of available resources that we can divvy up—and capacity limitations happen as we divide up those resources for use with particular memories, overextending ourselves too much. And our study shows a hybrid model is likely what is happening— resources are pooled, except there are actually two pools. And we can’t take resources from one pool and use them to help out the other pool.”

Dr. Buschman noted the separate pools of working-memory resources can be harnessed in several practical ways. He and Dr. Miller hope to build visual displays, such as heads-up displays (transparent displays of information that present information without requiring the viewer to look away, initially developed for aviation) that have similar amounts of information in the left and right sides. This would not overload viewers’ working-memory capacity and hence would allow more information on the displays to be retained and accessed.

“In addition, better brain-training games can be developed that isolate each visual hemisphere, targeting training to weaknesses in each hemisphere alone,” concluded Dr. Buschman.

Via:  Rosemary Frei, Freelance Journalist for “Betterbrainbetterlife.com”

When four is not four, but rather two plus two

MIT neuroscientists redefine the limits of visual working memory.

When it comes to working memory, the brain’s mental sketchpad, studies have largely converged on four as the magic number: It’s how many objects average adults can successfully hold in mind at once. Variations in this capacity are correlated with IQ — the more things you can think about simultaneously, the better able you are to make connections between them, and the “smarter” you’re considered.




But just why working memory can only juggle four items at a time has been poorly understood. Is working memory a discrete resource, meaning that once the four slots are filled, there’s simply no room for more objects? Or is it a flexible pool, divided more or less evenly among objects, and five or more cause it to be stretched too thin? Finally, where does the failure occur: in the initial perception of the objects, or later, in the remembering?

Now, MIT researchers have some answers. By studying visual working memory in monkeys — whose capacities are surprisingly similar to humans’ — they discovered that the limit of four can actually be broken down into two limits of two: one each for the left and right hemispheres of the brain. Because each hemisphere processes input from the right or left half of vision, memory for increasing numbers of objects depends on where in the visual field they appear.

“Surprisingly, we found that monkeys, and by extension humans, do not have a general capacity [for working memory] in the brain,” says Earl Miller, the Picower Professor of Neuroscience in MIT’s Picower Institute for Learning and Memory. “Rather, they have two independent, smaller capacities in the right and left halves of the visual space.”

So, not all groups of four objects are created equal: The brain can indeed remember up to four things, but it does best when those things are spaced out into two on the right side and two on the left. Any more than two on one side, and working memory starts to break down.

The results were published online this week in the Proceedings of the National Academy of Sciences (PNAS).

Sorry, can’t help you

In the researchers’ experiment, rhesus monkeys looked at an array of two to five colored squares on a black background. The screen went briefly blank, and then the squares reappeared — but this time, one square had changed color. The animals were trained to look at the changed square, or the “target,” to indicate that they knew which one it was. Previous research had predicted that the monkeys would do well on trials with up to four squares, but their performance would drop off when they had to remember five or more.

However, rather than the total number of objects across the array, the monkeys’ performance depended on the number of objects on each side of the visual space. For instance, even in certain trials with five objects — two on one side, three on the other — monkeys did fine, as long as the target object was one of the two. But in trials where the target was one of three objects all on the same side, even if there were no objects on the other side, monkeys were far less successful.

This suggests that visual working memory is split between the left and right side of the brain, and the two hemispheres are unable to transfer memory load between them. That is, if there are three objects on one side and only one on the other, the side with the lighter load can’t step in and relieve some of the other side’s burden. “Our study shows that both the slot and pool models are true,” Miller says. “The two hemispheres of the visual brain work like slots, but within each slot, it’s a pool.”

“The fact that we have different capacities in each hemisphere implies that we should present information in a way that does not overtax one hemisphere while undertaxing the other,” says Tim Buschman, a postdoc working with Miller and a co-author of the PNAS paper. “For example, heads-up displays [transparent projections of information that a driver or pilot would normally need to look down at the dashboard to see] show a lot of data. Our results suggest that you want to put that information evenly on both sides of the visual field to maximize the amount of information that gets into the brain.”

Breakdown from the bottom up

Furthermore, the researchers took recordings of neurons in the monkeys’ brains as they performed the visual task. They hoped this would shed light on where in the memory pathway the breakdown takes place: Does it happen as the monkeys are looking at the scene, failing to fully perceive it the first time around? Or do the monkeys see all the objects, but fail to encode what they’re seeing to be able to remember it later?

The researchers tracked visual information as it flowed from the parietal cortex, where sensory input is initially processed, to the frontal cortex, where higher-order structures encode it for memory. “We found that the bottleneck is not in the remembering, it is in the perceiving,” Miller says. Essentially, working memory for more than two objects in the same visual field was doomed from step one.

Recordings also showed that the total amount of information being processed increased from one to two objects, but that cortical areas became saturated after two, consistent with the idea that introducing more objects reduces the amount of information that can be stored about each one.

According to Edward Awh, a professor of psychology at the University of Oregon, one of the things that’s “very exciting” about this paper is the success of using neuronal recordings to examine working memory in non-human primates. “We haven’t gotten this kind of detailed cellular level information about the nature of capacity limits in working memory [before],” he says. He calls the strong lateralization between hemispheres in the monkey brain “curious and interesting,” but cautions against generalizing too quickly, since similar studies with humans have not found “such dramatic compartmentalization.”

Of course, if a similar phenomenon does exist in humans, it would have strong implications for how data should be presented to ensure maximum retention. Biomedical monitors that currently have one column of information should balance it in right and left columns, and security personnel could take in more information if displays scrolled vertically rather than horizontally, since horizontal scrolling doesn't fully take advantage of the independent capacities of the right and left.

In addition to Miller and Buschman, the PNAS paper was co-authored by Markus Siegel, another postdoc in Miller’s lab, and Jefferson Roy, a research scientist at the Picower Institute. In future studies, the researchers hope to discover why the perceptual bottleneck occurs in the first place, which would give “real insights into consciousness,” Miller says.

Via: MIT news