Posts tagged psychology
Articles and news from the latest research reports.
Brain scans reveal ‘grey matter’ differences in media multitaskers
Simultaneously using mobile phones, laptops and other media devices could be changing the structure of our brains, according to new University of Sussex research.
A study published today (24 September) in PLOS ONE reveals that people who frequently use several media devices at the same time have lower grey-matter density in one particular region of the brain compared to those who use just one device occasionally.
The research supports earlier studies showing connections between high media-multitasking activity and poor attention in the face of distractions, along with emotional problems such as depression and anxiety.
But neuroscientists Kep Kee Loh and Dr Ryota Kanai point out that their study reveals a link rather than causality and that a long-term study needs to be carried out to understand whether high concurrent media usage leads to changes in the brain structure, or whether those with less-dense grey matter are more attracted to media multitasking.
The researchers at the University of Sussex’s Sackler Centre for Consciousness Science used functional magnetic resonance imaging (fMRI) to look at the brain structures of 75 adults, who had all answered a questionnaire regarding their use and consumption of media devices, including mobile phones and computers, as well as television and print media.
They found that, independent of individual personality traits, people who used a higher number of media devices concurrently also had smaller grey matter density in the part of the brain known as the anterior cingulate cortex (ACC), the region notably responsible for cognitive and emotional control functions.
Kep Kee Loh says: “Media multitasking is becoming more prevalent in our lives today and there is increasing concern about its impacts on our cognition and social-emotional well-being. Our study was the first to reveal links between media multitasking and brain structure.”
Scientists have previously demonstrated that brain structure can be altered upon prolonged exposure to novel environments and experience. The neural pathways and synapses can change based on our behaviours, environment, emotions, and can happen at the cellular level (in the case of learning and memory) or cortical re-mapping, which is how specific functions of a damaged brain region could be re-mapped to a remaining intact region.
Other studies have shown that training (such as learning to juggle, or taxi drivers learning the map of London) can increase grey-matter densities in certain parts of the brain.
“The exact mechanisms of these changes are still unclear,” says Kep Kee Loh. “Although it is conceivable that individuals with small ACC are more susceptible to multitasking situations due to weaker ability in cognitive control or socio-emotional regulation, it is equally plausible that higher levels of exposure to multitasking situations leads to structural changes in the ACC. A longitudinal study is required to unambiguously determine the direction of causation.”
(Source: sussex.ac.uk)
(Image caption: This is a coronal view of the hippocampus brain region of a patient with Alzheimer’s disease. Image courtesy of Daniel Tranel’s Laboratory at the UI’s Department of Neurology.)
Alzheimer’s patients can still feel the emotion long after the memories have vanished
A new University of Iowa study further supports an inescapable message: caregivers have a profound influence—good or bad—on the emotional state of individuals with Alzheimer’s disease. Patients may not remember a recent visit by a loved one or having been neglected by staff at a nursing home, but those actions can have a lasting impact on how they feel.
The findings of this study are published in the September 2014 issue of the journal Cognitive and Behavioral Neurology.
UI researchers showed individuals with Alzheimer’s disease clips of sad and happy movies. The patients experienced sustained states of sadness and happiness despite not being able to remember the movies.
“This confirms that the emotional life of an Alzheimer’s patient is alive and well,” says lead author Edmarie Guzmán-Vélez, a doctoral student in clinical psychology, a Dean’s Graduate Research Fellow, and a National Science Foundation Graduate Research Fellow.
Guzmán-Vélez conducted the study with Daniel Tranel, UI professor of neurology and psychology, and Justin Feinstein, assistant professor at the University of Tulsa and the Laureate Institute for Brain Research.
Tranel and Feinstein published a paper in 2010 that predicted the importance of attending to the emotional needs of people with Alzheimer’s, which is expected to affect as many as 16 million people in the United States by 2050 and cost an estimated $1.2 trillion.
“It’s extremely important to see data that support our previous prediction,” Tranel says. “Edmarie’s research has immediate implications for how we treat patients and how we teach caregivers.”
Despite the considerable amount of research aimed at finding new treatments for Alzheimer’s, no drug has succeeded at either preventing or substantially influencing the disease’s progression. Against this foreboding backdrop, the results of this study highlight the need to develop new caregiving techniques aimed at improving the well-being and minimizing the suffering for the millions of individuals afflicted with Alzheimer’s.
For this behavioral study, Guzmán-Vélez and her colleagues invited 17 patients with Alzheimer’s disease and 17 healthy comparison participants to view 20 minutes of sad and then happy movies. These movie clips triggered the expected emotion: sorrow and tears during the sad films and laughter during the happy ones.
About five minutes after watching the movies, the researchers gave participants a memory test to see if they could recall what they had just seen. As expected, the patients with Alzheimer’s disease retained significantly less information about both the sad and happy films than the healthy people. In fact, four patients were unable to recall any factual information about the films, and one patient didn’t even remember watching any movies.
Before and after seeing the films, participants answered questions to gauge their feelings. Patients with Alzheimer’s disease reported elevated levels of either sadness or happiness for up to 30 minutes after viewing the films despite having little or no recollection of the movies.
Quite strikingly, the less the patients remembered about the films, the longer their sadness lasted. While sadness tended to last a little longer than happiness, both emotions far outlasted the memory of the films.
The fact that forgotten events can continue to exert a profound influence on a patient’s emotional life highlights the need for caregivers to avoid causing negative feelings and to try to induce positive feelings.
“Our findings should empower caregivers by showing them that their actions toward patients really do matter,” Guzmán-Vélez says. “Frequent visits and social interactions, exercise, music, dance, jokes, and serving patients their favorite foods are all simple things that can have a lasting emotional impact on a patient’s quality of life and subjective well-being.”
Infant Cooing, Babbling Linked to Hearing Ability
Infants’ vocalizations throughout the first year follow a set of predictable steps from crying and cooing to forming syllables and first words. However, previous research had not addressed how the amount of vocalizations may differ between hearing and deaf infants. Now, University of Missouri research shows that infant vocalizations are primarily motivated by infants’ ability to hear their own babbling. Additionally, infants with profound hearing loss who received cochlear implants to help correct their hearing soon reached the vocalization levels of their hearing peers, putting them on track for language development.
“Hearing is a critical aspect of infants’ motivation to make early sounds,” said Mary Fagan, an assistant professor in the Department of Communication Science and Disorders in the MU School of Health Professions. “This study shows babies are interested in speech-like sounds and that they increase their babbling when they can hear.”
Fagan studied the vocalizations of 27 hearing infants and 16 infants with profound hearing loss who were candidates for cochlear implants, which are small electronic devices embedded into the bone behind the ear that replace some functions of the damaged inner ear. She found that infants with profound hearing loss vocalized significantly less than hearing infants. However, when the infants with profound hearing loss received cochlear implants, the infants’ vocalizations increased to the same levels as their hearing peers within four months of receiving the implants.
“After the infants received their cochlear implants, the significant difference in overall vocalization quantity was no longer evident,” Fagan said. “These findings support the importance of early hearing screenings and early cochlear implantation.”
Fagan found that non-speech-like sounds such as crying, laughing and raspberry sounds, were not affected by infants’ hearing ability. She says this finding highlights babies are more interested in speech-like sounds since they increase their production of those sounds such as babbling when they can hear.
“Babies learn so much through sound in the first year of their lives,” Fagan said. “We know learning from others is important to infants’ development, but hearing allows infants to explore their own vocalizations and learn through their own capacity to produce sounds.”
In future research, Fagan hopes to study whether infants explore the sounds of objects such as musical toys to the same degree they explore vocalization.
Fagan’s research, “Frequency of vocalization before and after cochlear implantation: Dynamic effect of auditory feedback on infant behavior,” was published in the Journal of Experimental Child Psychology.
Brain Wave May Be Used to Detect What People Have Seen, Recognize
Brain activity can be used to tell whether someone recognizes details they encountered in normal, daily life, which may have implications for criminal investigations and use in courtrooms, new research shows.
The findings, published in Psychological Science, a journal of the Association for Psychological Science, suggest that a particular brain wave, known as P300, could serve as a marker that identifies places, objects, or other details that a person has seen and recognizes from everyday life.
Research using EEG recordings of brain activity has shown that the P300 brain wave tends to be large when a person recognizes a meaningful item among a list of nonmeaningful items. Using P300, researchers can give a subject a test called the Concealed Information Test (CIT) to try to determine whether they recognize information that is related to a crime or other event.
Most studies investigating P300 and recognition have been conducted in lab settings that are far removed from the kinds of information a real witness or suspect might be exposed to. This new study marks an important advance, says lead research John B. Meixner of Northwestern University, because it draws on details from activities in participants’ normal, daily lives.
“Much like a real crime, our participants made their own decisions and were exposed to all of the distracting information in the world,” he explains.
“Perhaps the most surprising finding was the extent to which we could detect very trivial details from a subject’s day, such as the color of umbrella that the participant had used,” says Meixner. “This precision is exciting for the future because it indicates that relatively peripheral crime details, such as physical features of the crime scene, might be usable in a real-world CIT — though we still need to do much more work to learn about this.”
To achieve a more realistic CIT, Meixner and co-author J. Peter Rosenfeld outfitted 24 college student participants with small cameras that recorded both video and sound — the students wore the cameras clipped to their clothes for 4 hours as they went about their day.
For half of the students, the researchers used the recordings to identify details specific to each person’s day, which became “probe” items for that person. The researchers also came up with corresponding, “irrelevant” items that the student had not encountered — if the probe item was a specific grocery store, for example, the irrelevant items might include other grocery stores.
For the other half of the students, the “probe” items related to details or items they had not encountered, but which were instead drawn from the recordings of other participants. The researchers wanted to simulate a real investigation, in which a suspect with knowledge of a crime would be shown the same crime-related details as a suspect who may have no crime-related knowledge.
The next day, all of the students returned to the lab and were shown a series of words that described different details or items (i.e., the probe and irrelevant items), while their brain activity was recorded via EEG.
The results showed that the P300 was larger for probe items than for irrelevant items, but only for the students who had actually seen or encountered the probe.
Further analyses revealed that P300 responses effectively distinguished probe items from irrelevant items on the level of each individual participant, suggesting that it is a robust and reliable marker of recognition.
These findings have implications for memory research, but they may also have real-world application in the domain of criminal law given that some countries, like Japan and Israel, use the CIT in criminal investigations.
“One reason that the CIT has not been used in the US is that the test may not meet the criteria to be admissible in a courtroom,” says Meixner. “Our work may help move the P300-based CIT one step closer to admissibility by demonstrating the test’s validity and reliability in a more realistic context.”
Meixner, Rosenfeld, and colleagues plan on investigating additional factors that may impact detection, including whether images from the recordings may be even more effective at eliciting recognition than descriptive words – preliminary data suggest this may be the case.
Brain Structure of Kidney Donors May Make Them More Altruistic
That’s the finding of a study published in today’s Proceedings of the National Academy of Sciences (PNAS) by Georgetown researchers.
Georgetown College psychology professor Abigail Marsh worked with John VanMeter, director of Center for Functional and Molecular Imaging at Georgetown University Medical Center, to scan the brains of 19 altruistic kidney donors.
More Sensitive to Distress
“The results of brain scans and behavioral testing suggests that these donors have some structural and functional brain differences that may make them more sensitive, on average, to other people’s distress,” Marsh explains.
The Georgetown researchers used functional MRI to record the neural activity of the kidney donors and 20 control subjects who had never donated an organ as they viewed faces with fearful, angry or neutral expressions.
Underlying Neural Basis
In the right amygdala, an emotion-sensitive brain region, altruists displayed greater neural activity while viewing fearful expressions than did control subjects.
When asked to identify the emotional expressions presented in the face images, altruists recognized fearful facial expressions relatively more accurately than the control subjects.
“The brain scans revealed that the right amygdala volume of altruists is larger than that of non-altruists,” Marsh says. “The findings suggest that individual differences in altruism may have an underlying neural basis.”
Opposite From Psychopaths?
These findings dovetail with previous research by the professor showing structural and functional brain differences that appear to make people with psychopathic traits less sensitive to others’ fear and distress.
These differences include amygdalas that are smaller and less responsive to fearful expressions. People who are unusually altruistic may therefore be the opposite in some ways from people who are psychopathic.
To find kidney donors, the researchers reached out to the Washington Regional Transplant Community (WRTC), a federally designated organ procurement organizations.
A Donor’s Story
Harold Mintz, former northern Virginian who volunteered with WRTC and agreed to participate in the Georgetown study, donated a kidney to an anonymous stranger he later learned was an Ethiopian refugee who had settled in Washington, D.C.
Mintz, who now lives in California and speaks to high school students about his 2000 donation, says a series of events over time led him to supply the kidney, including his father dying of cancer diagnosed too late at the age of 56.
One Valentine’s Day in 1988, Mintz and his wife were shopping separately for presents and Mintz noticed parents in a mall with a sign saying “Please Save Our Daughter’s Life.” He walked past them, then turned around and asked what they needed. It turned out the daughter had leukemia and needed a bone marrow transplant.
The couple decided to forget about the holiday and donated blood to see if either of them were a match. But no match was found and Mintz later noticed the daughter’s obituary in the newspaper.
Stories Taken to Heart
Mintz also was surprised to hear that although the couple’s daughter had just died, they thanked everyone who tried to help and expressed hope that they might help someone else.
“All these stories just kind of stuck inside my head and every time I’d see a story about a medical story of distress, it would just kind of get put away in a file inside my heart,” Mintz says.
Marsh notes that kidney disease is now the eighth-leading cause of death in the U.S., and that living kidney donations are the best hope for restoring people to health who have kidney disease.
“Dr. Marsh’s work is a great example of how fMRI can be used to provide insight into how differences in the brain’s response can lead individuals to perform such magnanimous acts,” VanMeter says.
This Is Your Brain on Snacks—Brain Stimulation Affects Craving and Consumption
Magnetic stimulation of a brain area involved in “executive function” affects cravings for and consumption of calorie-dense snack foods, reports a study in the September issue of Psychosomatic Medicine: Journal of Biobehavioral Medicine, the official journal of the American Psychosomatic Society. The journal is published by Lippincott Williams & Wilkins, a part of Wolters Kluwer Health.
After stimulation of the dorsolateral prefrontal cortex (DLPFC), young women experience increased cravings for high-calorie snacks—and eat more of those foods when given the opportunity, according to the study by researchers at University of Waterloo, Ont., Canada. “These findings shed a light on the role of the DLPFC in food cravings (specifically reward anticipation), the consumption of appealing high caloric foods, and the relation between self-control and food consumption,” the researchers write. The senior author was Peter Hall, PhD.
Brain Stimulation Affects Cravings and Consumption for ‘Appetitive’ Snacks
The study included 21 healthy young women, selected because they reported strong and frequent cravings for chocolate and potato chips. Such “appetitive,” calorie-dense snack foods are often implicated in the development of obesity.
The women were shown pictures of these foods to stimulate cravings. The researchers then applied a type of magnetic stimulation, called continuous theta-burst stimulation, to decrease activity in the DLPFC. Previous studies have suggested that DLPFC activity plays a role in regulating food cravings.
After theta-burst stimulation, the women reported stronger food cravings—specifically for “appetitive” milk chocolate and potato chips. During a subsequent “taste test,” they consumed more of these foods, rather than alternative, less-appetitive foods (dark chocolate and soda crackers).
Stimulation to weaken DLPFC activity was also associated with lower performance on a test of inhibitory control strength (the Stroop test). Decreased DLPFC activity appeared to be associated with increased “reward sensitivity”—it made the participants “more sensitive to the rewarding properties of palatable high caloric foods,” the researchers write.
Weak Executive Function May Contribute to Obesity Risk
The results highlight the role of executive function in governing “dietary self-restraint,” the researchers believe. Executive function, which involves the DLPFC, refers to a set of cognitive functions that enable “top-down” control of action, emotion, and thought.
At the “basic neurobiological level,” the study provides direct evidence that the DLPFC is involved in one specific aspect of food cravings: reward anticipation. People with weak executive function may lack the dietary self-control necessary to regulate snack food consumption in “the modern obesogenic environment.” Faced with constant cues and opportunities to consume energy-dense foods, such individuals may be more likely to become overweight or obese.
The results suggest that interventions aimed at enhancing or preserving DLPFC function may help to prevent obesity and related diseases. In conditions such as type 2 diabetes, where healthy dietary habits are essential for effective disease control, “Interventions focused on enhancing DLPFC activity, through aerobic exercise or other means, may result in increased dietary self-control and subsequently improve disease management,” Dr Hall and coauthors add.
(Source: newswise.com)
Study First to Use Brain Scans to Forecast Early Reading Difficulties
UC San Francisco researchers have used brain scans to predict how young children learn to read, giving clinicians a possible tool to spot children with dyslexia and other reading difficulties before they experience reading challenges.
In the United States, children usually learn to read for the first time in kindergarten and become proficient readers by third grade, according to the authors. In the study, researchers examined brain scans of 38 kindergarteners as they were learning to read formally at school and tracked their white matter development until third grade. The brain’s white matter is essential for perceiving, thinking and learning.
The researchers found that the developmental course of the children’s white matter volume predicted the kindergarteners’ abilities to read.
“We show that white matter development during a critical period in a child’s life, when they start school and learn to read for the very first time, predicts how well the child ends up reading,” said Fumiko Hoeft, MD, PhD, senior author and an associate professor of child and adolescent psychiatry at UCSF, and member of the UCSF Dyslexia Center.
The research is published online in Psychological Science.
Doctors commonly use behavioral measures of reading readiness for assessments of ability. Other measures such as cognitive (i.e. IQ) ability, early linguistic skills, measures of the environment such as socio-economic status, and whether there is a family member with reading problems or dyslexia are all common early factors used to assess risk of developing reading difficulties.
“What was intriguing in this study was that brain development in regions important to reading predicted above and beyond all of these measures,” said Hoeft.
The researchers removed the effects of these commonly used assessments when doing the statistical analyses in order to assess how the white matter directly predicted future reading ability. They found that left hemisphere white matter in the temporo-parietal region just behind and above the left ear — thought to be important for language, reading and speech — was highly predictive of reading acquisition beyond effects of genetic predisposition, cognitive abilities, and environment at the outset of kindergarten. Brain scans improved prediction accuracy by 60 percent better at predicting reading difficulties than the compared to traditional assessments alone.
“Early identification and interventions are extremely important in children with dyslexia as well as most neurodevelopmental disorders,” said Hoeft. “Accumulation of research evidence such as ours may one day help us identify kids who might be at risk for dyslexia, rather than waiting for children to become poor readers and experience failure.”
According to the National Institute of Child and Human Development, as many as 15 percent of Americans have major trouble reading.
“Examining developmental changes in the brain over a critical period of reading appears to be a unique sensitive measure of variation and may add insight to our understanding of reading development in ways that brain data from one time point, and behavioral and environmental measures, cannot,” said Chelsea Myers, BS, lead author and lab manager in UCSF’s Laboratory for Educational NeuroScience. “The hope is that understanding each child’s neurocognitive profiles will help educators provide targeted and personalized education and intervention, particularly in those with special needs.”
(Source: ucsf.edu)
Sometimes, adolescents just can’t resist
Don’t get mad the next time you catch your teenager texting when he promised to be studying.
He simply may not be able to resist.
A University of Iowa study found teenagers are far more sensitive than adults to the immediate effect or reward of their behaviors. The findings may help explain, for example, why the initial rush of texting may be more enticing for adolescents than the long-term payoff of studying.
“The rewards have a strong, perceptional draw and are more enticing to the teenager,” says Jatin Vaidya, a professor of psychiatry at the UI and corresponding author of the study, which appeared online this week in the journal Psychological Science. “Even when a behavior is no longer in a teenager’s best interest to continue, they will because the effect of the reward is still there and lasts much longer in adolescents than in adults.”
For parents, that means limiting distractions so teenagers can make better choices. Take the homework and social media dilemma: At 9 p.m., shut off everything except a computer that has no access to Facebook or Twitter, the researchers advise.
“I’m not saying they shouldn’t be allowed access to technology,” Vaidya says. “But they need help in regulating their attention so they can develop those impulse-control skills.”
In their study, “Value-Driven Attentional Capture in Adolescence,” Vaidya and co-authors Shaun Vecera, a professor of psychology, and Zachary Roper, a graduate student in psychology, note researchers generally believe teenagers are impulsive, make bad decisions, and engage in risky behavior because the frontal lobes of their brains are not fully developed.
But the UI researchers wondered whether something more fundamental was going on with adolescents to trigger behaviors independent of higher-level reasoning.
“We wanted to try to understand the brain’s reward system and how it changes from childhood to adulthood,” says Vaidya, who adds the reward trait in the human brain is much more primitive than decision-making. “We’ve been trying to understand the reward process in adolescence and whether there is more to adolescent behavior than an under-developed frontal lobe,” he adds.
For their study, the researchers recruited 40 adolescents, ages 13 and 16, and 40 adults, ages 20 and 35. First, participants were asked to find a red or green ring hidden within an array of rings on a computer screen. Once identified, they reported whether the white line inside the ring was vertical or horizontal. If they were right, they received a reward between 2 and 10 cents, depending on the color. For some participants, the red ring paid the highest reward; for others, it was the green. None was told which color would pay the most.
After 240 trials, the participants were asked whether they noticed anything about the colors. Most made no association between a color and reward, which researchers say proves the ring exercise didn’t involve high-level, decision-making.
In the next stage, participants showed they had developed an intuitive association when they were asked to find a diamond-shaped target. This time, the red and green rings were used as decoys.
At first, the adolescents and adults selected the color ring that garnered them the highest monetary reward, the goal of the first trial. But in short order, the adults adjusted and selected the diamond. The adolescents did not.
Even after 240 trials, the adolescents were still more apt to pick the colored rings.
“Even though you’ve told them, ‘You have a new target,’ the adolescents can’t get rid of the association they learned before,” Vecera says. “It’s as if that association is much more potent for the adolescent than for the adult.
“If you give the adolescent a reward, it will persist longer,” he adds. “The fact that the reward is gone doesn’t matter. They will act as if the reward is still there.”
Researchers say that inability to readily adjust behavior explains why, for example, a teenager may continue to make inappropriate comments in class long after friends stopped laughing.
In the future, researchers hope to delve into the psychological and neurological aspects of their results.
“Are there certain brain regions or circuits that continue to develop from adolescence to adulthood that play role in directing attention away from reward stimuli that are not task relevant?” Vaidya asks. “Also, what sort of life experiences and skill help to improve performance on this task?”
You are what you eat, the saying goes, and now a study conducted by researchers at UC Santa Barbara and the University of Pittsburgh suggests that the oft-repeated adage applies not just to physical health but to brain power as well.
In a paper published in the early online edition of the journal Prostaglandins, Leukotrienes and Essential Fatty Acids, the researchers compared the fatty acid profiles of breast milk from women in over two dozen countries with how well children from those same countries performed on academic tests.
Their findings show that the amount of omega-3 docosahexaenoic acid (DHA) in a mother’s milk — fats found primarily in certain fish, nuts and seeds — is the strongest predictor of test performance. It outweighs national income and the number of dollars spent per pupil in schools.
DHA alone accounted for about 20 percent of the differences in test scores among countries, the researchers found.
On the other hand, the amount of omega-6 fat in mother’s milk — fats that come from vegetable oils such as corn and soybean — predict lower test scores. When the amount of DHA and linoleic acid (LA) — the most common omega-6 fat — were considered together, they explained nearly half of the differences in test scores. In countries where mother’s diets contain more omega-6, the beneficial effects of DHA seem to be reduced.
More omega-3, less omega-6
“Human intelligence has a physical basis in the huge size of our brains — some seven times larger than would be expected for a mammal with our body size,” said Steven Gaulin, UCSB professor of anthropology and co-author of the paper. “Since there is never a free lunch, those big brains need lots of extra building materials — most importantly, they need omega-3 fatty acids, especially DHA. Omega-6 fats, however, undermine the effects of DHA and seem to be bad for brains.”
Both kinds of omega fat must be obtained through diet. But because diets vary from place to place, for their study Gaulin and his co-author, William D. Lassek, M.D., a professor at the University of Pittsburgh’s Graduate School of Public Health and a retired assistant surgeon general, estimated the DHA and LA content — the good fat and the bad fat — in diets in 50 countries by examining published studies of the fatty acid profiles of women’s breast milk.
The profiles are a useful measure for two reasons, according to Gaulin. First, because various kinds of fats interfere with one another in the body, breast milk DHA shows how much of this brain-essential fat survives competition with omega-6. Second, children receive their brain-building fats from their mothers. Breast milk profiles indicate the amount of DHA children in each region receive in the womb, through breastfeeding, and from the local diet available to their mothers and to them after they are weaned.
The academic test results came from the Programme for International Student Assessment (PISA), which administers standardized tests in 58 nations. Gaulin and Lassek averaged the three PISA tests — math, science and reading ability — as their measure of cognitive performance. There were 28 countries for which the researchers found information about both breast milk and test scores.
DHA content: best predictor of math test performance
“Looking at those 28 countries, the DHA content of breast milk was the single best predictor of math test performance,” Gaulin said. The second best indicator was the amount of omega-6, and its effect is opposite. “Considering the benefits of omega-3 and the detriment of omega-6, we can get pretty darn close to explaining half the difference in scores between countries,” he added. When DHA and LA are considered together, he added, they are twice as effective at predicting test scores as either is alone, Gaulin said.
Gaulin and Lassek considered two economic factors as well: per capita gross domestic product (a measure of average wealth in each nation) and per student expenditures on education. “Each of these factors helps explain some of the differences between nations in test scores, but the fatty acid profile of the average mother’s milk in a given country is a better predictor of the average cognitive performance in that country than is either of the conventional socioeconomic measures people use,” said Gaulin.
From their analysis, the researchers conclude that both economic wellbeing and diet make a difference in cognitive test performance, and children are best off when they have both factors in their favor. “But if you had to choose one, you should choose the better diet rather than the better economy,” Gaulin said.
The current research follows a study published in 2008 that showed that the children of women who had larger amounts of gluteofemoral fat “depots” performed better on academic tests than those of mothers with less. “At that time we weren’t trying to identify the dietary cause,” explained Gaulin. “We found that this depot that has been evolutionarily elaborated in women is important to building a good brain. We were content at that time to show that as a way of understanding why the female body is as evolutionarily distinctive as it is.”
Now the researchers are looking at diet as the key to brain-building fat, since mothers need to acquire these fats in the first place.
Their results are particularly interesting in 21st-century North America, Gaulin noted, because our current agribusiness-based diets provide very low levels of DHA — among the lowest in the world. Thanks to two heavily government-subsidized crops — corn and soybeans — the average U.S. diet is heavy in the bad omega-6 fatty acids and far too light on the good omega-3s, Gaulin said.
Wrong kind of polyunsaturated fat
“Back in the 1960s, in the middle of the cardiovascular disease epidemic, people got the idea that saturated fats were bad and polyunsaturated fats were good,” he explained. “That’s one reason margarine became so popular. But the polyunsaturated fats that were increased were the ones with omega-6, not omega-3. So our message is that not only is it advisable to increase omega 3 intake, it’s highly advisable to decrease omega-6 — the very fats that in the 1960s and ’70s we were told we should be eating more of.”
Gaulin added that mayonnaise is, in general, the most omega-6-laden food in the average person’s refrigerator. “If you have too much of one — omega-6 — and too little of the other — omega 3 — you’re going to end up paying a price cognitively,” he said.
The issue is a huge concern for women, Gaulin noted, because “that’s where kids’ brains come from. But it’s important for men as well because they have to take care of the brains their moms gave them.
“Just like a racecar burns up some of its motor oil with every lap, your brain burns up omega-3 and you need to replenish it every day,” he said.
(Image: Stacy Librandi)
Yogic breathing shows promise in reducing symptoms of post-traumatic stress disorder
One of the greatest casualties of war is its lasting effect on the minds of soldiers. This presents a daunting public health problem: More than 20 percent of veterans returning from the wars in Iraq and Afghanistan have post-traumatic stress disorder, according to a 2012 report by RAND Corp.
A new study from the Center for Investigating Healthy Minds at the Waisman Center of the University of Wisconsin-Madison offers hope for those suffering from the disorder. Researchers there have shown that a breathing-based meditation practice called Sudarshan Kriya Yoga can be an effective treatment for PTSD.
Individuals with PTSD suffer from intrusive memories, heightened anxiety, and personality changes. The hallmark of the disorder is hyperarousal, which can be defined as overreacting to innocuous stimuli, and is often described as feeling “jumpy,” or easily startled and constantly on guard.
Hyperarousal is one aspect of the autonomic nervous system, the system that controls the beating of the heart and other body functions, and governs one’s ability to respond to his or her environment. Scientists believe hyperarousal is at the core of PTSD and the driving force behind some of its symptoms.
Standard treatment interventions for PTSD offer mixed results. Some individuals are prescribed antidepressants and do well while others do not; others are treated with psychotherapy and still experience residual affects of the disorder.
Sudarshan Kriya Yoga is a practice of controlled breathing that directly affects the autonomic nervous system. While the practice has proven effective in balancing the autonomic nervous system and reducing symptoms of PTSD in tsunami survivors, it has not been well studied until now.
The CIHM team was interested in Sudarshan Yoga because of its focus on manipulating the breath, and how that in turn may have consequences for the autonomic nervous system and specifically, hyperarousal. Theirs is the first randomized, controlled, longitudinal study to show that the practice of controlled breathing can benefit people with PTSD.
"This was a preliminary attempt to begin to gather some information on whether this practice of yogic breathing actually reduces symptoms of PTSD," says Richard J. Davidson, founder of CIHM and one of the authors of the study. "Secondly, we wanted to find out whether the reduction in symptoms was associated with biological measures that may be important in hyperarousal."
These tests included measuring eye-blink startle magnitude and respiration rates in response to stimuli such as a noise burst in the laboratory. Respiration is one of the functions controlled by the autonomic nervous system; the eye-blink startle rate is an involuntary response that can be used to measure one component of hyperarousal. These two measurements reflect aspects of mental health because they affect how an individual regulates emotion.
The CIHM study included 21 soldiers: an active group of 11 and a control group of 10. Those who received the one-week training in yogic breathing showed lower anxiety, reduced respiration rates and fewer PTSD symptoms.
Davidson would like to further the research by including more participants, with the end goal of enabling physicians to prescribe treatment based on the cognitive and emotional style of the individual patient.
"A clinician could use a ‘tool box’ of psychological assessments to determine the cognitive and emotional style of the patient, and thereby determine a treatment that would be most effective for that individual," he says. "Right now, a large fraction of individuals who are given any one type of therapy are not improving on that therapy. The only way we can improve that is if we determine which kinds of people will benefit most from different types of treatments."
That assessment is critical. At least 22 veterans take their own lives every day, according to the U.S. Department of Veterans Affairs. Because Sudarshan Kriya Yoga has already been shown to increase optimism in college students, and reduce stress and anxiety in people suffering from depression, it may be an effective way to decrease suffering and, quite possibly, the incidence of suicide among veterans.
The study, published in the Journal of Traumatic Stress, was funded by a grant from the Disabled Veterans of America Charitable Service Trust and individual donors.
(Source: news.wisc.edu)