Louis_J_Sheehan

Break a mirror and you’re stuck with bad luck. Walk under a ladder and you’re tempting fate. Sound ridiculous? Scientists believe such beliefs may be genetic, part of adaptive behaviors passed on to create an evolutionary advantage to surviving impeding danger.

Boiled down, a superstition is the belief that one event caused another event, without any evidence of the link. “All animals will display behaviors that imply a causal relationship that isn’t there,” says Kevin Foster, evolutionary biologist at Harvard University. Foster uses a pigeon as an example: The pigeon will take flight if it hears a hand clap, the same way it would react if it heard a gun shot.

Foster collaborated with Hanna Kokko of the University of Helsinki to build computer models to create simulations of what happens when an animal links a cause-and-effect event to avoid danger. The team compared real dangers, like the sound of rustling grass when a predator approaches, to the sound of rustling grass caused by something innocuous, like the wind. The researchers presumed that even though the animal might be overreacting to the harmless sounds, when a predator is actually approaching, the superstitious behavior could save its life.

Likewise, the researchers said that in humans, the superstitious belief that walking under a ladder will give you bad luck is a result of common sense: Others have, in all likelihood, gotten hurt from walking under a ladder due to the inherent danger of being in a construction zone. http://www.Louis9J9Sheehan9esquire.blog.ca

The researchers concluded that people adopt these behaviors to make sense of the world around them in the context of their culture. Therefore humans tend to associate events in their lives, and sometimes end up making “superstitious mistakes.”

We say, so what: Just cross your fingers. Louis J. Sheehan

Louis J. Sheehan. Cutting way back on calorie intake for six months doesn’t take a bite out of bones in people who haven’t yet reached middle age, a new study shows.

The finding, reported online and in the Sept. 22 Archives of Internal Medicine, thickens the debate over calorie restriction: A 2006 study had suggested that quick weight loss weakened bones in people over age 50. http://Louissheehan.BraveDiary.com

The current study looks at volunteers with average ages in the late 30s. It’s possible that the reports’ different results stem from the age discrepancy, says Luigi Fontana, a physician and gerontologist at Washington University in St. Louis who coauthored the earlier study.

Calorie restriction — eating fewer calories than necessary for maintaining a steady body weight — seems to offer health benefits and possibly a way to stretch a person’s longevity. But researchers are now investigating whether there might be a downside to the practice, apart from being hungry.

The new study focused on bone density over a short time period, as measured by X-rays before volunteers began dieting and again after the volunteers had dieted for six months. Leanne Redman, an endocrinologist at the Pennington Biomedical Research Center of Louisiana State University in Baton Rouge, and her colleagues randomly assigned 46 healthy but slightly overweight people to maintain one of four diets for that time period. Each diet group included roughly a dozen volunteers.

One group served as a control, eating a normal, healthy diet about equal to their energy output each day. Another group achieved a net energy deficit of 25 percent by eating fewer calories, while a third group achieved the same deficit through a combination of dieting and exercise. People in the fourth group drew the short straw, assigned to consume a very restrictive diet of only 890 calories a day — about half the daily average typically needed to maintain weight — until they achieved a 15 percent weight loss. At that point they switched to a diet that maintained a steady weight for the remainder of the study. All volunteers also took calcium and vitamin D supplements.

The controls lost 1 percent of body weight on average, whereas the two calorie-restricted groups, whether exercising or not, lost 10 percent of their body weight. People in the fourth group, who were on the strictest low-cal diet, lost 14 percent of body weight.

Despite these sharp losses, none of the groups showed a significant change in bone mineral density over the half-year study. Heavier people have more bone because the stress on their frame demands it, Redman says. The bone density remained unchanged in these people, whether adjusted for a change in weight, she says. http://Louissheehan.BraveDiary.com

The 2006 study found some bone density losses during a one-year trial in which participants maintained slightly less arduous calorie restriction than in the new study. But those losses didn’t show up in people who also exercised. That trial also comprised slightly overweight volunteers, but they averaged about 20 years older than participants in the new study.

The two studies are part of the initial wave of calorie restriction studies in people, Fontana says. “Women over 50 who are post-menopausal are already losing bone due to the fact that they are estrogen deficient,” he says. Men also show a loss, although it’s less abrupt. To clarify the issue of calorie restriction and risk of bone loss, Fontana says, researchers will need to go beyond bone density measurements and actually record bone fractures over a longer time period. Such studies will reveal overall bone quality and not merely density, he says. Louis J. Sheehan

Louis J. Sheehan. Seated before a computer screen, 85-year-old Madeline Hanson watches a story about Molly, a character in a yellow dress who is baking a cake in a kidney-shaped swimming pool. A helicopter flies down with a beater to whip the batter. Then, through headphones, Hanson hears a voice slowly ask: “What color is Molly’s dress? What shape is the swimming pool?”

The video game, created by Posit Science of San Francisco, is a tough mental workout dressed up in an entertaining package. It is one of a slew of novel cognitive training programs being marketed by neuroscientists for the purpose of rejuvenating aging brains. Other researchers with the same goal are promoting the targeted use of more conventional games and hobbies—for instance, playing Scrabble or bird-watching. These strategies, new evidence suggests, drive changes in neural pathways that underlie learning and may actually beef up the brain. http://louis-j-sheehan.info

Fun, engrossing activities are strongly encoded in memory because they engage our emotions, according to James Gee, a cognitive scientist at Arizona State University. “Any information associated with pleasure and excitement triggers dopamine release,” he says. Dopamine fosters exploration in search of reward, causing newly acquired knowledge, in Gee’s words, “to be stored more deeply and better remembered later.” Other neurochemicals that reinforce learning are stimulated by novelty, attention to fine detail, and attaining goals—all common features of games.

The latest crop of training programs attempt to exploit these insights into the brain’s inner workings to bolster learning and mental acuity. Hanson, at least, is convinced that Posit Science’s intense video exercise has made her sharper. Recent studies confirm her perception, suggesting that game-based approaches can bring about stunning gains in episodic memory, attention, and agility of thought. Jeff Zimman, CEO and cofounder of Posit, says, “We’re at the beginning of a revolution in brain fitness that is akin to the physical fitness craze that took off in the 1970s.”

Less than a decade ago, most scientists accepted as an article of faith that our neural circuitry settles into its adult configuration by the end of childhood, but recent years have revealed that the mature brain is far from a static organ. Throughout life, stimulating activities spark the growth of new nerve connections and may even prompt a key memory center of the brain to produce neurons.

In 2006 British cognitive neuroscientist Eleanor Maguire discovered that London taxi drivers have literally grown into their jobs: A part of their brains involved in spatial memory is significantly larger than the same site in the brains of London bus drivers, who travel a fixed route. Musicians also show distinct neural changes. Behavioral neuroscientist Edward Taub of the University of Alabama at Birmingham finds that string instrument players devote more cortical real estate to the fingers that form notes on the strings than to the digits of the opposite hand, which simply clasps the bow. Taub says that musicians who begin playing as late as their forties may develop this pattern—more evidence that challenges can rewire the brain well into adulthood. Just-released research by gerontologist Elizabeth Zelinski of the University of Southern California goes even further, showing that people typically retain a great deal of brain plasticity well into their seventies.

Other studies bolster the case that intellectual pursuits help build neural reserves: richer, more efficient connections that help the brain compensate as it runs down with age. The more years of education people have, the longer it takes for them to fall victim to memory-robbing diseases like Alzheimer’s. People who are socially active or who engage in stimulating leisure activities experience a delay in mental decline. And the more time people spend in these engrossing pastimes, the greater their protection against age-related cognitive decline, notes Gene Cohen, a gerontologist at George Washington University in Washington, D.C. The Einstein Aging Study, conducted by Albert Einstein College of Medicine in New York City, shows that people who do crossword puzzles four days a week are half as likely to develop dementia as those who do them infrequently.

As people play video games, their visual-spatial acuity improves and their reaction times are faster.

It is too early to predict whether younger generations weaned on video games and other interactive electronic entertainment will be afforded similar protection, but early indicators are encouraging. “As people play video games, their visual-spatial acuity improves—especially their peripheral vision—and their reaction times are much faster,” reports Gary Small, director of the Center on Aging at UCLA. Cognitive scientists estimate that nearly half the information we assimilate enters through our eyes, and as we grow older, our ability to pay attention to things on the periphery declines. At the same time, the aged brain processes the stream of visual data much more slowly. Any activity that keeps these visual circuits in better working order may improve overall cognitive functioning.

Electronic games that require complex strategies and creative problem solving may exercise still more parts of the brain. These kinds of challenges, says Gee of Arizona State, build planning, memory, and reasoning skills. Some computer games that have commanded a massive following among children and young adults—for example, World of Warcraft—may even fine-tune social areas of the brain. As Gee points out, these games are played online with thousands or even millions of other devotees around the globe, and success depends on collaboration and teamwork.

The new appreciation of the brain’s ability to remodel itself in response to stimulation, coupled with baby boomers’ dread of mental decay, is spawning a burgeoning industry that promises a cognitive fountain of youth. Brain boot camps in which individuals are intensively drilled in mnemonic strategies are springing up across the country (one of them is led by Small). Books like The Memory Bible are selling briskly. So are electronic games like Nintendo DS’s Brain Age, played on a handheld game platform with a touch-sensitive screen. Web sites such as MyBrainTrainer.com proffer mental gymnastics touted to sharpen the mind. Cohen has just joined the fray, marketing a board game that aims to increase brain plasticity among patients suffering from Alzheimer’s or stroke-related dementia. In the game, players pick out pictures of friends and relatives and are asked questions about them.

Most neuroscientists agree that such approaches are probably helpful, but few purveyors of these products offer clinical data to support their claims. Nor is it clear how the impact of these strategies compares with the effects of decades of reading, playing a musical instrument, or other passions pursued over a lifetime. “Whether the benefits are modest or great, we just don’t know,” says John Gabrieli, professor in the department of brain and cognitive sciences at MIT. “The manufacturers don’t even try to develop that information.”
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A notable exception is Posit Science, which markets Brain Fitness, the video training program used by Hanson. Brain Fitness was developed by a team of neuro­scientists led by Michael Merzenich, a coinventor of both the cochlear implant and a highly regarded software package for treating dyslexia in children (see “The Elastic Brain” by Katherine Ellison in DISCOVER, May 2007). Merzenich insists on getting independent researchers to evaluate the efficacy of Brain Fitness. His latest results are encouraging enough to have had a trickle-down effect, aiding the credibility of the whole brain-fitness movement.

Strategies modeled on Brain Fitness are being developed for attention deficit disorder.

The Posit Science system strives to enhance the speed and accuracy of auditory processing and recall in the elderly. Exercises that become progressively more difficult teach discrimination of tones of different frequencies and speech sounds that the elderly often confuse. In many instances the computer slows down difficult-to-discern syllables and then gradually speeds them up to match the more challenging conditions in which natural conversation occurs. Like a game, the program engages the user with funny, whimsical stories and has other built-in rewards to stoke motivation.

The earliest clinical tests of Brain Fitness, from 2006, were preliminary and regarded with caution. Sherry L. Willis, professor of human development at Pennsylvania State University, expressed doubts at the time about brain-boosting programs in general. “The researchers need to see if they can train more-complex abilities, if they’re durable over five years, and whether training on these skills will transfer to everyday functioning,” she said.

Now an expanded investigation of the Posit Science method—the largest test ever of a widely available computer-based cognitive intervention—answers most of those questions. A randomized, prospective trial, it has involved 437 people 65 and older who either received 40 hours of training with Brain Fitness or spent the same duration of time in a placebo intervention that consisted of watching educational DVDs and taking quizzes afterward. Last November at the annual meeting of the Gerontological Society of America, researchers reported results of the study. Compared with the control group, the Brain Fitness subjects increased their information processing speed (on tasks like picking out key details from a conversation) an average of 131 percent. Overall they showed a 10-year improvement in memory, so that 75-year-olds displayed the auditory recall of a typical 65-year-old. Subjects reported that they could hear better in noisy restaurants and recall names more easily; they were also less inclined to grope for words in midsentence. (Posit Science paid for the study, but some trials were conducted by outside scientists with no financial stake in the company, such as Zelinski at USC and neuropsychologist Glenn Smith at the Mayo Clinic in Rochester, Minnesota.)

Brain-plasticity training might also help older people struggling with memory disturbances of a more serious nature, according to MIT’s Gabrieli and cognitive neuroscientist Allyson Rosen at Stanford University. The two researchers evaluated the Brain Fitness program’s impact on patients diagnosed with mild cognitive impairment (MCI), a condition that typically progresses to Alzheimer’s within a few years. Six of the subjects did the standard Brain Fitness course; another six, constituting the control group, played a video game and read The New York Times. Over a two-month trial, all six subjects in the control group showed a decline in the activation of the left hippocampus, which processes auditory memory, and on average deteriorated on tests of verbal recall. In contrast, five out of the six subjects in the treatment group showed no reduction of activity in the hippocampus and on average improved their performance on verbal memory tests.

“Even though the study was very small, the findings were so robust that the results were statistically significant,” Gabrieli says. He cautions that more research is needed to confirm the benefits of the intervention, but he is enthusiastic about its potential: “The main thrust of treatment for MCI [pdf] has been drug development, but drugs have side effects and so far have not been very effective. This is a much more naturalistic approach toward rejuvenating the brain.”

It is not clear how well these results apply to other brain-plasticity tools based on games and play because Merzenich’s approach is rather different from other behavioral strategies. Most mental training programs on the market emphasize the learning of mnemonic tricks. Those may be useful for younger people, Merzenich argues, but for the older person they are like “kicking a dead horse.” A major reason cognitive function declines with age, he says, is that “the brain’s decoding process is degraded, and if you can’t fix that then you can’t restore memory.”

A young person processes about 8 to 10 auditory samples per syllable; an 80-year-old processes fewer than 2 samples per syllable. “That’s why the older individual’s understanding of speech and verbal memory are so fuzzy, and the same is true of the visual system,” Merzenich says. The only way to remedy the situation, in his view, is to speed up neural processing by challenging the brain with increasingly difficult stimuli. For his next version of Brain Fitness, Merzenich is expanding the program, which currently emphasizes auditory processing, to include exercises that strengthen visual processing as well as complex reasoning and planning. When the whole package is put together, he says, “I honestly believe we’re going to see 25 to 30 years in cognitive rejuvenation. That means the average 80-year-old will function cognitively like a 50-year-old.” http://louis-j-sheehan.info

That is a grand goal, far beyond what Posit has achieved to date or what the current brain-plasticity studies have documented. But if Merzenich is right, a strenuous approach could do much more than mere fun and games to help the elderly maintain the intellectual firepower of their youth. Regular brain workouts may benefit other groups as well; strategies modeled on Brain Fitness are now being developed for youngsters with attention deficit disorder and for people suffering from head trauma, schizophrenia, and chemotherapy fog.

“We’re just at the start of figuring out what a really smart, systematic, and aggressive approach to behavioral intervention can achieve,” Gabrieli says. “It’s an exciting time.” exercises 0000200.14
Louis J. Sheehan

Louis J. Sheehan. From molecular genetics to brain imaging, neuroscientists churn out so much data that only a small fraction ever appears in their published work. And therein lies a conflict.

Efforts now under way would require neuroscientists to make all of their data available for analysis by other researchers. That has inspired praise from some quarters and criticism from others.

In the September Nature Neuroscience, Stephen H. Koslow of the National Institute of Mental Health in Bethesda, Md., argues that neuroscientists need to establish a system to pool and analyze experimental data. Koslow heads a government-funded initiative attempting to organize a network of databases that would serve as a library of neuroscience information. Data sharing through such a system will yield better experiments and faster scientific advances, he predicts. http://majestic-12-louis-j-sheehan-esquire.blogspot.com

Still, many investigators worry that by immediately giving away all of their data, other scientists will use it to beat them to the punch with new revelations. Stay tuned, says Koslow. Louis J. Sheehan

Louis J. Sheehan. The old saying that it’s better to give than to receive may be true, at least when it comes to social support. Over a 5-year period, seniors who provided either a lot of practical assistance to friends, relatives, and neighbors or regular emotional support to their spouses displayed a higher survival rate than those who didn’t provide such help, a new study finds. http://majestic-12-louis-j-sheehan-esquire.blogspot.com

In contrast, recipients of plentiful social support showed death rates similar to those of their peers who got little or no such support, say psychologist Stephanie L. Brown of the University of Michigan in Ann Arbor and her colleagues.

Nearly all previous attempts to link social contacts and physical health have focused only on whether individuals receive support from others. Results have been mixed. http://majestic-12-louis-j-sheehan-esquire.blogspot.com

“Giving support may be an important component of interpersonal relationships that has considerable value to health and well-being,” Brown’s group concludes in the July Psychological Science. It’s not yet known whether programs that teach ways to provide support to others would boost long-term survival rates, the researchers add.

The scientists examined data previously collected from 423 married couples living in and around Detroit. The couples were part of a larger prospective study of coping and grief reactions in the elderly.
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Each husband was 65 years of age or older at the start of the study in 1987; most wives were slightly younger. Over the next 5 years, 134 individuals died.

Statistical analyses of various subgroups revealed a lower death rate, by as much as half, for participants who reported in initial surveys that they had been providing either of two types of social support. One type involved helping people other than one’s spouse with errands, housework, childcare, or other daily tasks. The other centered on listening to one’s spouse when he or she needed to talk and making that person feel loved and cared for.

The survival advantage for support givers remained when the researchers statistically controlled for individual differences in age, physical health, satisfaction with health, exercise, cigarette and alcohol use, mental health, and income. The findings also held after controlling for differences in extroversion, agreeableness, feeling vulnerable to stress, and other personality measures.

Still, the scientists note, more extensive research is needed to rule out the possibilities that the physically healthiest people most often provide social support and thus live longer or that an abundance of material resources fosters longevity and makes it easier to give aid to others.

Brown’s study offers a fresh way to think about social support, remarks psychologist Camille B. Wortman of the State University of New York at Stony Brook. Wortman directs the larger project on coping among the elderly from which Brown and her coworkers drew their data.

“It’s worthwhile to raise the question of whether giving social support, rather than receiving it, results in health benefits among those undergoing stress,” Wortman says. Louis J. Sheehan

Louis J. Sheehan

Mothers throughout the world talk to their babies using common conventions, such as raising the pitch and exaggerating the emotional tone of their voices. There’s now evidence that moms in different cultures also use three distinctive facial expressions to communicate with their infants.

The three maternal expressions differ from adult oriented facial displays of emotion, such as those for happiness, sadness, and surprise, say psychologist Janet F. Werker of the University of British Columbia in Vancouver and her coworkers. http://louis8j8sheehan8esquire.wordpress.com

Puckering and slightly spreading the lips, often with a slight smile or subtle eyebrow raise, make a facial expression dubbed “oochie” by the scientists. Moms use this look to convey concern and caring, say the scientists propose in the September Infant and Child Development. http://louis8j8sheehan8esquire.wordpress.com

Raising the eyebrows sharply while opening and stretching the mouth, with a hint of a smile, yields the so-called “wow” expression. This display imparts a mother’s sense of pride in her baby.

Finally, smiling and raising the cheeks with a slightly open mouth produces the “joy” expression, which also features what Werker calls “an unmistakable look of love in the eyes.” Mothers adopt this expression to communicate a mix of affection and happiness, the scientists suggest.

Werker’s team videotaped 10 Canadian mothers and 10 Chinese mothers interacting with their 4-to 7-month-old babies. Given a stack of pictures of the mothers taken from the tapes, 32 college students easily identified each of the expressions. Another 40 students and 35 mothers of infants reported close agreement on what each facial display meant.

Further research needs to explore whether mothers in other cultures, as well as fathers and nonparents, make the same three faces at babies. Louis J. Sheehan

Louis J. Sheehan
Count on evolution to play favorites. When it comes to math achievement, some kids may start out with an inherent advantage.

A portion of 14-year-olds deftly estimate approximate quantities of items without counting, whereas others do so with either moderate or limited success, a new study finds. The ability is evolutionarily ancient and cannot be taught, but tends to get better with age. Large variations in this number sense closely parallel youngsters’ mathematics achievement scores from kindergarten to sixth grade, concludes a team reporting in the Sept. 7 Nature and led by psychologist Justin Halberda of Johns Hopkins University in Baltimore.

Earlier studies indicated that a faculty for rapidly estimating approximate quantities appears by age 4 months, long before any math instruction. How precisely a child can estimate amounts may influence math learning and achievement, Halberda proposes. He and his colleagues are now assessing this ability in 3-year-olds whose math achievement in elementary school will be tracked.

It’s also possible that high-quality or intensive math instruction may increase the accuracy of a person’s number estimates. Halberda suspects that if such effects exist, they’re relatively small.

“Our results suggest that there is a strong and significant relationship between the acuity of a student’s approximate number system and his or her performance in school mathematics,” the Hopkins researcher says.

Until now, he adds, researchers have ignored individual differences in people’s ability to estimate quantities quickly and without counting. “We found much greater variability from one person to another than we would have predicted,” Halberda says.

“Halberda’s group provides a beautiful demonstration of a link between a measure of number sense and classical measures of math achievement,” comments cognitive neuroscientist Stanislas Dehaene of the INSERM-CEA Cognitive Neuroimaging Unit in Gif-sur-Yvette, France. Unlike Halberda, Dehaene considers it likely that higher degrees of mathematical training markedly boost the precision of rapid quantity estimates.

In Halberda’s study, 64 healthy 14-year-olds attending regular classes in public schools viewed arrays of blue and yellow dots on a computer screen. Each array appeared for a fraction of a second, making it impossible to count dots. The number of dots of each color varied from five to 16. Dots also varied in size to ensure that greater numbers of one color did not cover a larger total area than smaller numbers of the other color, thus giving away the more numerous set of dots.

Top-performing teens estimated quantities as well as mathematically astute adults have in earlier studies. The teens discriminated between numerical ratios of blue and yellow dots as close as 9 to 10. Low-performing volunteers, who estimated quantities at about the level of 2-year-olds, had difficulty discriminating between numerical ratios higher than 2 to 3.

Individual performance on the approximation task corresponded closely with scores on two standard math achievement tests the participants had taken from kindergarten through sixth grade. This finding held after statistically accounting for IQ, spatial reasoning ability, working memory capacity and more than a dozen other cognitive measures.

It’s not clear how a faculty for estimating approximate amounts would aid in learning arithmetic operations consisting of exact numbers, as suggested in the new study, remarks psychologist Brian Butterworth of University College London.

“Arithmetic requires a sense of exact number — approximate numbers just won’t do,” Butterworth asserts. In other words, formal math learning may depend on an inherent ability to recognize anywhere from exactly one to perhaps six or seven items, but not on the ability to estimate the number of items.

In the Sept. 2 Proceedings of the National Academy of Sciences, Butterworth and his coworkers report that 4- to 7-year-olds who speak either of two languages that have few number words identify and remember small quantities of items as well as English-speakers of the same age. Number words in those two languages roughly correspond to one, few and many.

Another study, led by Michael Frank, a psychology graduate student at the Massachusetts Institute of Technology, suggests that an Amazonian tribe has no number words but can still count small quantities (7/19/08, p. 5).

“These new results are surprising and the study is well-conducted,” Frank says of Halberda’s work.

In other work, Butterworth has found no relationship between several measures of approximate number estimation and tests of various math skills among 23 healthy 8- and 9-year-olds. He and his colleagues present their findings in the September Developmental Science. http://louis8j8sheehan8esquire.wordpress.com

A handful of recent studies have reached the same conclusion, Halberda notes. But all of them, including Butterworth’s, examine the performance of groups of children rather than probing for individual differences in the precision of estimates, he says. Statistical links to math achievement only emerge when researchers account for those individual disparities, in his view.

An inborn ability to track precise numbers of items may be crucial for grasping math concepts, as Butterworth argues, or it might only assist in learning number words, Frank adds. http://louis8j8sheehan8esquire.wordpress.com