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Category: brain

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Very important research looking at some professional football players who started playing tackle football before the age of 12, and comparing them to those who started later. It discusses the issue of whether children should be playing tackle football before the age of 12 - these and other results suggest NOT. Wait till older (or don't play tackle at all).This article came from Boston University through Futurity:

Is This Kid Too Young For Football?

Researchers from Boston University School of Medicine found that former National Football League (NFL) players who participated in tackle football before the age of 12 are more likely to have memory and thinking problems as adults.

The study contradicts conventional wisdom that children’s more plastic brains might recover from injury better than those of adults, and suggests that they may actually be more vulnerable to repeated head impacts, especially if injuries occur during a critical period of growth and development. "

“This is one study, with limitations,” adds study senior author Robert Stern, a professor of neurology, neurosurgery, and anatomy and neurobiology and director of the Alzheimer’s Disease Center’s Clinical Core. “But the findings support the idea that it may not make sense to allow children—at a time when their brain is rapidly developing—to be exposed to repetitive hits to the head.”

In the study, researchers reexamined data from Boston University’s ongoing DETECT(Diagnosing and Evaluating Traumatic Encephalopathy Using Clinical Tests) study, which aims to develop methods of diagnosing chronic traumatic encephalopathy (CTE) during life. CTE is a neurodegenerative disease often found in professional football players, boxers, and other athletes who have a history of repetitive brain trauma. It can currently be diagnosed only by autopsy.

For this latest study, published in the journal Neurology, scientists examined test scores of 42 former NFL players, with an average age of 52, all of whom had experienced memory and thinking problems for at least six months. Half the players had played tackle football before age 12, and half had not. Significantly, the total number of concussions was similar between the two groups.

Researchers found that the players exposed to tackle football before age 12 had greater impairment in mental flexibility, memory, and intelligence—a 20 percent difference in some cases. These findings held up even after statistically removing the effects of the total number of years the participants played football. Both groups scored below average on many of the tests.

Stamm says the researchers were especially surprised by the scores on a reading test called the WRAT-4, which has participants read words of increasing difficulty....The low scores may be significant, she says, because they suggest that repeated head trauma at a young age might limit peak intelligence. She emphasizes, however, that there may be other reasons for a low score, and that more research is needed.

The authors chose age 12 as the cutoff because significant peaks in brain development occur in boys around that age. (This happens for girls a bit earlier, on average.) Around age 12, says Stern, blood flow to the brain increases, and brain structures such as the hippocampus, which is critical for memory, reach their highest volume.

Boys’ brains also reach a peak in their rate of myelination—the process in which the long tendrils of brain cells are coated with a fatty sheath, allowing neurons to communicate quickly and efficiently. Because of these developmental changes, Stern says, this age may possibly represent a “window of vulnerability,” when the brain may be especially sensitive to repeated trauma.

Stern adds that a study by another group of researchers of the number and severity of hits in football players aged 9 to 12, using accelerometers in helmets, found that players received an average of 240 high-magnitude hits per season, sometimes with a force similar to that experienced by high school and college players.

With approximately 4.8 million athletes playing youth football in the United States, the long-term consequences of brain injury represent a growing public health concern. This study comes at a time of increasing awareness of the dangers of concussions—and subconcussive hits—in youth sports like football, hockey, and soccer. In 2012, Pop Warner football, the oldest and largest youth football organization in the country, changed its rules to limit contact during practices and banned intentional head-to-head contact. 

“Football has the highest injury rate among team sports,” writes Christopher M. Filley, a fellow with the American Academy of Neurology, in an editorial accompanying the Neurology article. “Given that 70 percent of all football players in the United States are under the age of 14, and every child aged 9 to 12 can be exposed to 240 head impacts during a single football season, a better understanding of how these impacts may affect children’s brains is urgently needed.”

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This study is important because it shows (once again) that spatial skills may be developed by what a child does in childhood. The trend for girls to only be given dolls or stereotypically "girl" toys is not that good for mental development (but good for nurturing). All children need to play with blocks, puzzles, and to create and build. They all need to go out and actively explore their environment, which also is good for developing spatial reasoning skills (as shown by earlier research). Think about it: when you actively explore the streets and land around you, you develop "mental maps" of how to get around, and this is good for spatial skills. Bottom line: encourage both boys and girls to build, create, do puzzles, play board games, and explore their outside environment. From Science Daily:

Playing with puzzles, blocks may build children's spatial skills

Play may seem like fun and games, but new research shows that specific kinds of play are actually associated with development of particular cognitive skills. Data from an American nationally representative study show that children who play frequently with puzzles, blocks, and board games tend to have better spatial reasoning ability.

"Our findings show that spatial play specifically is related to children's spatial reasoning skills," says psychological scientist and lead researcher Jamie Jirout of Rhodes College. "This is important because providing children with access to spatial play experiences could be a very easy way to boost spatial development, especially for children who typically have lower performance, such as girls and children from lower-income households."

Being able to reason about space, and how to manipulate objects in space, is a critical part of everyday life, helping us to navigate a busy street, put together a piece of "some assembly required" furniture, even load the dishwasher. And these skills are especially important for success in particular academic and professional domains, including science, technology, engineering, and math (STEM).

Jirout and Newcombe analyzed data from 847 children, ages 4 to 7, who had taken the revised WPPSI [Wechsler Preschool and Primary Scale of Intelligence], which included measures of cognitive skills that contribute to general intelligence. The children's spatial ability was specifically measured via the commonly-used Block Design subtest of the WPPSI, in which children are asked to reproduce specific 2D designs using cubes that have red, white, and half-red/half-white faces. The researchers also examined survey data from parents about the children's play behavior and joint parent-child activities.

The data revealed that family socioeconomic status, gender, and general intelligence scores were all associated with children's performance on the block design task. Children from the low-socioeconomic status group tended to have lower block design scores compared to children from either the middle- or high-socioeconomic status groups. And boys tended to have higher block design scores than did girls, though only after several other cognitive abilities, such as vocabulary, working memory, and processing speed, were taken into account.

Importantly, how often children played with certain toys was also tied to their spatial reasoning skills. Children who played with puzzles, blocks, and board games often (more than six times per week) had higher block design scores than did children who played with them sometimes (three to five times per week), or rarely/never.

None of the other types of play (e.g., drawing, playing with noise-making toys, and riding a bicycle, skateboard, or scooter) or the parent-child activities (e.g., teaching number skills, teaching shapes, playing math games, telling stories) included in the survey data were associated with children's spatial ability.

In line with previous findings, parents reported that boys engaged in spatial play -- playing with puzzles, blocks, and board games -- more often than girls, even after spatial ability was taken into account.

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Finding an increased risk of dementia and Alzheimer's with so many common over-the-counter medications such as Benadryl and  Chlortrimeton (the first generation allergy drug that so many people took for years) was an unpleasant surprise. Note: they found the link with high doses or heavy use (3 or more years). Some examples of common anticholinergics (from Wikipedia) are: atropine, benztropine (Cogentin), chlorpheniramine (Chlor-Trimeton), dimenhydrinate (Dramamine), diphenhydramine (Benadryl, Sominex, Advil PM, etc.), doxylamine (Unisom), hydroxyzine (Atarax, Vistaril), ipratropium (Atrovent), oxybutynin (Ditropan, Driptane, Lyrinel XL), tolterodine (Detrol, Detrusitol), tiotropium (Spiriva), and bupropion (Zyban, Wellbutrin). The message here: only take medications when absolutely needed and for as little a time as necessary. The study was done on older adults, so now the question is: what about children or young adults who take these drugs for years? Is there a similar increased risk later in life? From Medical Daily:

Common Over-The-Counter Anticholinergic Drugs Like Benadryl May Increase Your Risk Of Alzheimer's

Anticholinergic medications span a range of common drugs and include antihistamines, sleep aids, antidepressants, cardiovascular meds, gastrointestinal drugs (for diarrhea, incontinence, diverticulitis, and ulcers), and muscle relaxants. Now, a new study confirms the link between these everyday medications and dementia. Taking anticholinergic drugs at high doses or for a long time may significantly increase your risk for developing Alzheimer's disease and other dementias, say researchers from University of Washington School of Pharmacy.

“If providers need to prescribe a medication with anticholinergic effects because it is the best therapy for their patient, they should use the lowest effective dose, monitor the therapy regularly to ensure it's working, and stop the therapy if it's ineffective,” Dr. Shelly Gray, a professor and director of the geriatric pharmacy program at the UW School of Pharmacy said in a release.

On average, older people take four or five prescription drugs and two over-the-counter drugs each day. Clearly, drugs are an important part of medical care for older people; however, older people are more sensitive to the effects of many pills, including anticholinergics, which block the neurotransmitter acetylcholine and so effect the nervous system. While the drugs are too numerous to mention, those with anticholinergic effects — and these effects are sometimes dependent on the dose — include Benadryl, Sominex, Xanax, Ativan, Valium, Luminal, Skelaxin, Limbitrol, and Tavist.

For the current study, the researchers investigated a previously reported link between anticholinergics, both prescription strength and over-the-counter, and dementia by employing more rigorous methods than in the past. Specifically, the researchers conducted a longer follow-up of more than seven years and more accurate use assessment via pharmacy records, which included nonprescription choices. The team tracked nearly 3,500 seniors participating in a long-running study, the Adult Changes in Thought (ACT), a joint project of UW and the National Institute on Aging.

The most commonly used medications in the study, the researchers discovered, were tricyclic antidepressants like doxepin (Sinequan), antihistamines like chlorpheniramine (Chlor-Trimeton), and antimuscarinics for bladder control like oxybutynin (Ditropan). People taking at least 10 mg/day of doxepin, 4 mg/day of diphenhydramine, or 5 mg/day of oxybutynin for more than three years, the researchers estimated, would be at greater risk for developing dementia. Importantly, substitutes are available for some of these drugs.  

While this study is the first to show a dose response — meaning, the more you use anticholinergic medications the greater your risk of developing Alzheimer’s — it also is the first to suggest this higher risk may persist, and may not be reversible, even years after you stop taking these drugs. 

Source: Gray S, Crane P, Dublin S, et al. Cumulative Use of Strong Anticholinergic Medications and Incident Dementia. JAMA Internal Medicine. 2015.

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Exercise has health benefits at all ages! From Medical Xpress:

Study indicates exercise sharpens the young adult brain

Regular physical activity improves brain function even in young adults considered in their prime and at the height of cognitive ability, according to a new University of Otago study.

They took 52 tertiary students, aged from 18 to 30, and put them through a series of cognitive tests on a computer while measuring oxygen availability in the frontal lobe of their brains, as well as their self-reported exercise frequency. Dr Machado says their "surprising" findings, just published online in the journal Psychophysiology, show that both blood supply to the brain and cognitive functioning appear to benefit from regular exercise in young adults.

"This provides compelling evidence that regular exercise, at least 5 days per week, is a way to sharpen our cognitive ability as young adults – challenging the assumption that living a sedentary lifestyle leads to problems only later in life," she says... "The exercise could involve brisk walking or more vigorous activity, and could be made up of a few 10 minute bouts of exercise, rather than one single block of exercise," she says.

The researchers also found that body mass index was not a key factor in how well the brain functioned, indicating that regular engagement in physical activity may be more important than body weight.

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Over the past year I have seen a number of studies looking at alcohol consumption and health effects. Overall it seems that the effects of alcohol are complex and frequently result in a J-curve: abstainers have a higher mortality rate or problems, light or moderate drinkers do the best, and then heavier drinkers have the most problems and higher mortality rates. The following two studies support this. From Science Daily:

Drinking moderate amounts of alcohol is linked to reduced risk of heart failure, large study finds

Evidence already exists for the beneficial effects of drinking moderate amounts of alcohol on the risk of developing a number of heart conditions; however, the role it plays in the risk of developing heart failure has been under-researched with conflicting results. Now, a large study of nearly 15,000 men and women shows that drinking up to seven drinks a week in early to middle age is associated with a 20% lower risk of men developing heart failure in the future when compared to people who did not drink at all, and a more modest 16% reduced risk for women.

They defined a drink as one that contains 14g of alcohol, equivalent to approximately one small (125ml) glass of wine, just over half a pint or a third of a litre of beer, and less than one shot of liquor such as whisky or vodka. The study participants were divided into six categories: abstainers (people who recorded having drunk no alcohol at every visit by the researchers), former drinkers, people who drank up to seven drinks a week, or between 7-14 drinks, 14-21 drinks, or 21 or more drinks a week.

From Science Daily:

If you're over 60, drink up: Alcohol associated with better memory

For people 60 and older who do not have dementia, light alcohol consumption during late life is associated with higher episodic memory -- the ability to recall memories of events -- researchers report.

Moderate alcohol consumption was also linked with a larger volume in the hippocampus, a brain region critical for episodic memory. The relationship between light alcohol consumption and episodic memory goes away if hippocampal volume is factored in, providing new evidence that hippocampal functioning is the critical factor in these improvements.

Findings from animal studies suggest that moderate alcohol consumption may contribute to preserved hippocampal volume by promoting generation of new nerve cells in the hippocampus. In addition, exposing the brain to moderate amounts of alcohol may increase the release of brain chemicals involved with cognitive, or information processing, functions.

Although the potential benefits of light to moderate alcohol consumption to cognitive learning and memory later in life have been consistently reported, extended periods of abusing alcohol, often defined as having five or more alcoholic beverages during a single drinking occasion is known to be harmful to the brain.

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Try standing on one leg with your eyes open, Can you do it for longer than 20 seconds? From Science Daily:

Ability to balance on one leg may reflect brain health, stroke risk

Struggling to stand on one leg for less than 20 seconds was linked to an increased risk for stroke, small blood vessel damage in the brain, and reduced cognitive function in otherwise healthy people, a study has shown. One-legged standing time may be a simple test used to measure early signs of abnormalities in the brain associated with cognitive decline, cerebral small vessel disease and stroke.

The study consisted of 841 women and 546 men, average age of 67. To measure one-leg standing time, participants stood with their eyes open and raised one leg. The maximum time for keeping the leg raised was 60 seconds. Participants performed this examination twice and the better of the two times was used in the study analysis. Cerebral small vessel disease was evaluated using brain magnetic resonance imaging.

Researchers found that the inability to balance on one leg for longer than 20 seconds was associated with cerebral small vessel disease, namely small infarctions without symptoms such as lacunar infarction and microbleeds. They noted that: 34.5 percent of those with more than two lacunar infarction lesions had trouble balancing, 16 percent of those with one lacunar infarction lesion had trouble balancing, 30 percent of those with more than two microbleed lesions had trouble balancing, 15.3 percent one microbleed lesion had trouble balancing.

Overall, those with cerebral diseases were older, had high blood pressure and had thicker carotid arteries than those who did not have cerebral small vessel disease. However, after adjustment for these covariates, people with more microbleeds and lacunar infarctions in the brain had shorter one-legged standing times. Short one-legged standing times were also independently linked with lower cognitive scores.

Small vessel disease occurs due to microangiopathy of arterioles in the brain, making these arteries less flexible, which can interfere with blood flow. Small vessel disease typically increases with age. Loss of motor coordination, including balance, as well as cognitive impairment has been suggested to represent subclinical brain damage. Tabara and colleagues also found a strong link between struggling to stand on one leg and increased age, with marked shorter one-leg standing time in patients age 60 and over.

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Bottom line: view the games as fun and a way to pass some time, but nothing more. From the Atlantic:

The Myth of the Brain Game

Over the past decade, digital brain-training games have emerged as the newest way to sharpen memory skills. They’re often touted as having a wide range of benefits, from helping people remember names and childhood stories to possibly staving off dementia and Alzheimer's disease.

In October, Stanford University’s Center for Longevity and the Max Planck Institute for Human Development in Berlin asked a group of more than 70 neuroscientists, cognitive psychologists, and academics to share their views on these games. “There is little evidence that playing brain games improves underlying broad cognitive abilities, or that it enables one to better navigate a complex realm of everyday life,” the group wrote in a consensus report.

The validity of brain games has been a point of debate ever since the first iterations of them launched in the early 2000s. What’s notable about the Stanford/Max Planck report is its deliberation and scope, offering insight collected over the course of a year from experts based at 40 institutions in six different countries.

The report questions the “pernicious,” “exaggerated,” and “misleading” claims made by brain-game manufacturers and stresses that wide-reaching positive results are “elusive.” The signatories don’t call out any specific types of brain-training software, but their language is often damning. “Many scientists cringe at exuberant advertisements claiming improvements in the speed and efficiency of cognitive processing and dramatic gains in ‘intelligence,’” they write.

Brain training is projected to be a $3 billion industry by 2015. Its target demographic is vast, from kids lagging behind in school to seniors who’d love to be able to remember things more efficiently. Most people, in fact, would appreciate the opportunity to feel like they’re getting the most out of their brains, and when a particular product is advertised as being both educational and backed by science, it can be hard to resist.

That there’s a need for scientists to issue a signed letter like this one only goes to show how popular brain games are and to what extent experts feel the public may have been seduced by the promise that they’re endorsed by science. The letter is both a word of caution to the public and the signatories’ way of distancing themselves from the commercial products. 

In 2013, two researchers at the University of Oslo and University College London conducted a meta-analysis of 23 different brain-training studies. What they saw was what every skeptic has seemed to notice. “Memory training programs appear to produce short-term, specific training effects that do not generalize,” they wrote. That is, training with games helped people get better at the games they were playing, but not much else.

Brain games aren’t a complete waste of time. They provide mental stimulation, the kind that doctors advise the elderly to get from crosswords and other mind games. They are fun, engaging, even competitive. They show how we can train the brain to get better at a task with repeated practice. But these are fairly obvious results given what we know about the brain's plasticity. 

All that said, the things that do help shape a healthy brain are the things that have been tried and tested for years. Physical fitness forces more blood to flow into the brain, allowing for more neural connections. So exercise works, as does conventional training in reading and language skills for children with reading-comprehension and oral language difficulties.

Also helpful are curiosity and engagement with the world around us, and the body’s lifelong subconscious effort to keep the brain active. The report's summary is perhaps the biggest indictment of any pop-a-pill brain-game philosophy. “The promise of a magic bullet detracts from the best evidence to date,” they wrote. “Cognitive health in old age reflects the long-term effects of healthy, engaged lifestyles.”

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Great news for coffee lovers, especially for those drinking 3 to 5 cups daily! From Medical Daily:

Drinking Coffee Can Lower Alzheimer's Risk By 20%, All It Takes Is 3 Cups A Day

As if you weren’t already drinking a lot of coffee, a review of several studies has found drinking three to five cups a day could reduce risk of Alzheimer’s disease by 20 percent.

The research was presented at the 2014 Alzheimer Europe Annual Congress, and found that people who drank coffee regularly — all you lifers out there — were less likely to develop the debilitating disease. Alzheimer’s, perhaps the worst type of dementia, is a progressive disease that works slowly, first making it difficult to remember newly learned things, and later on making it difficult to remember early memories and family member’s faces, while also causing hallucinations. The biggest risk factor for the disease is being over 65 years old.

Roughly 83 percent of American adults drink coffee, according to the National Coffee Association. What many of these Americans don’t know, however, is that inside that cup of Joe is a wealth of polyphenols, which you probably know as antioxidants. These antioxidants — researchers said they’re the same ones found in the Mediterranean diet — prevent the formation of a hallmark of Alzheimer’s disease known as amyloid plaques and neurofibrillary tangles, the study found. They also reduce inflammation and deterioration of brain cells, particularly in the areas of the brain (the hippocampus and cortex) responsible for memory.

Along with prevention of Alzheimer’s, coffee has been linked to a reduced risk of liver cancer and other liver conditions, a lower risk of type 2 diabetes; it prevents eye damage and Parkinson’s disease; and even boosts endurance. But even then, drinking too much isn’t good, either. As the researchers noted, three to five cups is optimal; anything over that, and you might find yourself with some problems.

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This research finding of lower IQ in children with higher exposure to 2 common phthalates during pregnancy is very troubling. Especially since avoiding all phthalates in the USA is currently impossible. But one can lower levels in the body by reading all ingredients and trying to avoid certain products (e.g. dryer sheets, vinyl shower curtains, personal care products with phthalates, scented products). And don't microwave food in plastic containers. From Science Daily:

Prenatal exposure to common household chemicals linked with substantial drop in child IQ

Children exposed during pregnancy to elevated levels of two common chemicals found in the home -- di-n-butyl phthalate and di-isobutyl phthalate -- had an IQ score, on average, more than six points lower than children exposed at lower levels, according to researchers.

DnBP and DiBP are found in a wide variety of consumer products, from dryer sheets to vinyl fabrics to personal care products like lipstick, hairspray, and nail polish, even some soaps. Since 2009, several phthalates have been banned from children's toys and other childcare articles in the United States. 

Researchers followed 328 New York City women and their children from low-income communities. They assessed the women's exposure to four phthalates--DnBP, DiBP, di-2-ethylhexyl phthalate, and diethyl phthalate--in the third trimester of pregnancy by measuring levels of the chemicals' metabolites in urine. Children were given IQ tests at age 7.

Children of mothers exposed during pregnancy to the highest 25 percent of concentrations of DnBP and DiBP had IQs 6.6 and 7.6 points lower, respectively, than children of mothers exposed to the lowest 25 percent of concentrations after controlling for factors like maternal IQ, maternal education, and quality of the home environment that are known to influence child IQ scores. The association was also seen for specific aspects of IQ, such as perceptual reasoning, working memory, and processing speed. The researchers found no associations between the other two phthalates and child IQ. The range of phthalate metabolite exposures measured in the mothers was not unusual: it was within what the Centers for Disease Control and Prevention observed in a national sample.

"A six- or seven-point decline in IQ may have substantial consequences for academic achievement and occupational potential.""While there has been some regulation to ban phthalates from toys of young children," adds Dr. Factor-Litvak, "there is no legislation governing exposure during pregnancy, which is likely the most sensitive period for brain development. Indeed, phthalates are not required to be on product labeling."

While avoiding all phthalates in the United States is for now impossible, the researchers recommend that pregnant women take steps to limit exposure by not microwaving food in plastics, avoiding scented products as much as possible, including air fresheners, and dryer sheets, and not using recyclable plastics labeled as 3, 6, or 7.

The findings build on earlier, similar observations by the researchers of associations between prenatal exposure to DnBP and DiBP and children's cognitive and motor development and behavior at age 3. This September, they reported a link between prenatal exposure to phthalates and risk for childhood asthma. It's not known how phthalates affect child health. However, numerous studies show that they disrupt the actions of hormones, including testosterone and thyroid hormone. Inflammation and oxidative stress may also play a role.

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More discussion of the benefits of vitamin D. From Science Daily:

Vitamin D deficiency, depression linked in international study

Vitamin D deficiency is not just harmful to physical health -- it also might impact mental health, according to a team of researchers that has found a link between seasonal affective disorder, or SAD, and a lack of sunlight. "Rather than being one of many factors, vitamin D could have a regulative role in the development of SAD," said Alan Stewart of the University of Georgia College of Education.

Stewart and Michael Kimlin from QUT's School of Public Health and Social Work conducted a review of more than 100 leading articles and found a relationship between vitamin D and seasonal depression."Seasonal affective disorder is believed to affect up to 10 percent of the population, depending upon geographical location, and is a type of depression related to changes in season," said Stewart, an associate professor in the department of counseling and human development services.

"We believe there are several reasons for this, including that vitamin D levels fluctuate in the body seasonally, in direct relation to seasonally available sunlight," he said. "For example, studies show there is a lag of about eight weeks between the peak in intensity of ultraviolet radiation and the onset of SAD, and this correlates with the time it takes for UV radiation to be processed by the body into vitamin D.

Vitamin D is also involved in the synthesis of serotonin and dopamine within the brain, both chemicals linked to depression, according to the researchers. "Evidence exists that low levels of dopamine and serotonin are linked to depression, therefore it is logical that there may be a relationship between low levels of vitamin D and depressive symptoms," said Kimlin, a Cancer Council Queensland Professor of Cancer Prevention Reseach. "Studies have also found depressed patients commonly had lower levels of vitamin D."

Vitamin D levels varied according to the pigmentation of the skin. People with dark skin often record lower levels of vitamin D, according to the researchers.

Kimlin, who heads QUT's National Health and Medical Research Council Centre for Research Excellence in Sun and Health, said adequate levels of vitamin D were essential in maintaining bone health, with deficiency causing osteomalacia in adults and rickets in children. Vitamin D levels of more than 50 nanomoles per liter are recommended by the U.S. Institute of Medicine...."A few minutes of sunlight exposure each day should be enough for most people to maintain an adequate vitamin D status."