A tide of recent research on early childhood development is inspiring prominent scientists and politicians to argue for an unprecedented investment in schooling that begins virtually at birth.

But as decades of academic studies on brain development start to land in the real world, experts are divided on whether to focus new funding on infants and toddlers, or conventional preschool. Many now think some policies popular with politicians and the public, such as universal prekindergarten, may fail to reach at-risk kids at a young enough age.

The scientific controversy also is spilling into the presidential contest, where the Democratic candidates have taken divergent positions on universal preschool and other early childhood issues.

Studies have suggested that intervening before children start preschool improves academic outcomes for low-income kids and may reduce the risk that they will end up in prison. Such interventions stem from the theory that experiences in the first five years of life set a lifelong course for brain development.

Chicago has become a national proving ground for schooling during the first three years and is home to prominent advocates such as Nobel Prize-winning economist James Heckman of the University of Chicago, who said reaching kids before preschool could offer the best long-term economic return.

“Even at age 4 or 5, you may be starting too late,” Heckman said. “I wouldn’t say it’s hopeless to help kids after those early years, but it’s extremely expensive.”

Backers of universal preschool say the evidence for even earlier intervention is not yet solid and offering conventional prekindergarten to everyone would help build popular support for early education.

In theory, starting to intervene soon after birth should help kids more because that’s when experience starts to shape their brains, many experts said.

Children’s brains change more between conception and kindergarten than at any other time. University of Chicago neuroscientist Peter Huttenlocher showed in studies over the last 30 years that connections between cells in most brain areas peak by age 3, then decline gradually as experiences mold the brain’s circuitry.

The zero-to-3 period is not necessarily a magical and irreplaceable window for teaching children. But studies show that babies raised in poverty get fewer of the early experiences that spur vocabulary growth and good social judgment, making it harder for them to catch up later.

For example, toddlers whose parents speak more words to them develop bigger vocabularies than children who hear less speech, studies have found. One University of Kansas study concluded that kids from upper-income backgrounds hear 30 million more words by age 3 than those from poor families.

Early intervention with enrichment programs can narrow that gap, researchers and advocates say.

“The basic science of brain development says you need to start as early as possible for kids in the greatest danger to get the best outcomes,” said Jack Shonkoff, director of the Center on the Developing Child at Harvard University.

Bruce Fuller, a professor of education and public policy at the University of California-Berkeley, said he feared focusing on universal prekindergarten — making preschool a middle-class entitlement — could divert help from low-income families that need it most.

“Why would we use scarce public dollars to subsidize all families if we know the biggest impact is with poor kids?” he said.

Source: Detroit Free Press, United States
http://www.freep.com/apps/pbcs.dll/article?AID=/20080502/NEWS07/805020328

For generations, scholars have debated whether language constrains the ways we think. Now, neuroscientists studying reading disorders have begun to wonder whether the actual character of the text itself may shape the brain.

Studies of schoolchildren who read in varying alphabets and characters suggest that those who are dyslexic in one language, say Chinese or English, may not be in another, such as Italian.

Among children raised to read and write Chinese, the demands of reading draw on parts of the brain untouched by the English alphabet, new neuroimaging studies reveal. It’s the same with dyslexia, psychologist Li Hai Tan at Hong Kong Research University and his colleagues reported last month in the Proceedings of the National Academy of Sciences. The problems occur in areas not involved in reading other alphabets.

Using two brain-imaging techniques, they identified striking differences in neural anatomy and brain activity between children able to read and write Chinese easily and classmates struggling to keep pace. Both were at odds with patterns of brain activity among readers of the English alphabet.

Even when readers in both languages looked at the same written characters, the brain activity was different, other researchers found. Arabic numerals of standard arithmetic — used by readers of Chinese and English alike — activate different brain regions depending on which of the two languages people had first learned to read, researchers at the Chinese Academy of Sciences and China’s Dalian University of Technology reported in 2006.

“In this sense, we may regard dyslexia in Chinese and English as two different brain disorders,” Dr. Tan said, “because completely different brain regions are disrupted. It’s very likely that a person who is dyslexic in Chinese would not be dyslexic in English.”

By any measure, reading is a complex and peculiar task. At the speed of thought, readers of English turn letters they see into sounds, sounds into words, and words into meaning. Fluency is measured in milliseconds. Spelling variations are speed bumps in the brain.

Until recently, researchers who study reading abilities focused mostly on Western alphabets. English and 218 other languages, from Alsatian to Zulu, share variations of the same Latin character set. But that set is only one of 60 writing systems used among the world’s remaining 6,912 spoken languages. Even so, those studies convinced many scientists and educators that the brain’s response to the written word, regardless of the language, is universal.

The new research suggests they’re wrong. The schooling required to read English or Chinese may fine-tune neural circuits in distinctive ways.

“We have to recognize that the writing system in China is different, the demands on the brain are different and the characteristics of dyslexia are different,” said Georgetown University pediatric learning specialist Guinevere Eden, who is incoming president of the International Dyslexia Association.

To document the effects on brain development, Dr. Eden and her colleagues are launching a five-year study in Beijing and Washington to compare the neural changes in 60 schoolchildren learning to read either Chinese or English. “Nobody has ever done this across two writing systems,” Dr. Eden said.

In ways that ancient scribes never imagined, text has transformed us. Every brain shaped by reading, whether it is schooled in Chinese or English text, measurably differs — in terms of patterns of energy use and brain structure — from one that has never mastered the written word, comparative brain-imaging studies show. “There are real differences that emerge because of literacy,” Dr. Wolf said.

Some social psychologists speculate that the brain changes caused by literacy could be involved in cultural differences in memory, attention and visual perception. In January’s Psychological Science, MIT researchers reported that European-Americans and students from several East Asian cultures, for example, showed different patterns of brain activation when making snap judgments about visual patterns.

No one knows which came first: habits of thought or the writing system that gave them tangible form. A writing system could be drawn from the archaeology of the mind, perpetuating aspects of mental life conceived at the dawn of civilization.

“Once you have different writing systems in place,” said University of Michigan social psychologist Richard Nisbett. “They may reinforce the perceptual and cognitive trends that preceded the invention of writing. They may go hand in glove.”

Source: Wall Street Journal
http://tinyurl.com/6c4gax

What does my baby know? When does my baby start to learn? How do you teach a baby?

Twenty-five years ago, the answers to these questions were unclear; there was much conjecture and many hypotheses on just what happens when infants interact with the people and objects in their environment. Observation and testing provided many tantalizing clues, but what was actually going on within those precious little heads still remained a mystery.

In recent years, new and nonintrusive brain-scanning technology has allowed scientists to watch in real time the brain-stimulation effects of a wide range of seemingly simple activities, beginning in the earliest weeks of life.

It turns out, infants quickly know an amazing amount of things: Just days after birth, they can recognize familiar faces, smells and sounds; soon after birth they can differentiate every vocal sound produced by human languages (and by six months they have already begun to sort out the common sounds of the languages they hear most frequently). At birth, they begin expressing rudimentary emotional expressions, and by two months they can express more complex emotions, such as sadness or frustration.

While these infants are literally growing smarter daily, their parents are often feeling the opposite effect; the addition of this little genius to the family has thrown their personal and family routines into disarray, priorities are now inverted and diapers and feeding cycles are an obsession they never believed they’d share. All parents need and deserve support in this time of transition.

What to do with this information is the challenge; for many parents in today’s two-wage-earner economy, just spending a few waking hours with their baby is a stretch — especially when it is the baby’s sleep schedule that determines when a waking hour occurs.

While we’d all like to give our littlest ones every advantage from day one, parents are overwhelmed with opinions, options and advice, much of it contradictory.

New parents can prepare to be their child’s first and best teacher by first acknowledging that none of us can do this alone. Connecting with their peers to share the challenges and opportunities, acknowledging their common needs and sharing resources, information and skills will build confidence and competence in those critical first few months of the adventure of parenting.

Source: Seattle Times, United States
http://seattletimes.nwsource.com/html/opinion/2004371716_harryhoffman25.html

Research is First to Describe How Neurons Interpret Different Words

You might be able to hear the difference, but to many children and adults, these words sound exactly the same. The problem isn’t that they can’t hear the sounds. The problem is that they can’t tell them apart.

One in 20 children in kindergarten has difficulties understanding speech that are not related to hearing or problems with their ears. The reason is that speech discrimination is a problem solved in the brain, not in the ear. How does the brain process speech sounds? Very little was known, until now.

Enter Dr. Michael Kilgard and Crystal Engineer. Kilgard is a neuroscientist in the School of Behavioral and Brain Sciences at the University of Texas at Dallas. His lab is one of the few in the world that studies how individual neurons process speech stimuli. Engineer is one of Professor Kilgard’s doctoral students. Together they conducted a study to provide the first-ever description of how speech sounds are processed by neurons in the brain. This insight may offer a new approach to treating children with speech processing disorders.

“Now that we’ve cracked the door on this important problem, we should be able to understand the neural basis of many common speech processing disorders and use this information to develop new treatments,” said Dr. Kilgard.

The study is part of Engineer’s dissertation, “Cortical activity patterns predict speech discrimination ability,” and will be published in the May issue of Nature Neuroscience, the top research journal in the field of neuroscience. The advance, online publication of the study is now available on the Nature Neuroscience Web site.

This research is groundbreaking for a number of reasons. Prior studies have used a synthetic voice and tested the response to only a few words. Engineer and Kilgard had a much broader scope. They tested all the consonant sounds in the English language using a human voice. Microelectrodes inserted into a rat’s auditory cortex enabled the researchers to capture the patterns of neural activity generated by each consonant with incredible precision. Recording techniques that can be used with human subjects (such as MRI and EEG) lack the precision to track the activity of individual neurons.

The recordings showed that contrary to prior belief it’s not the quantity of neurons that fire in response to a speech sound that is important. It is which neurons are firing and exactly when they are firing – down to the millisecond – that is critical.

Based on the patterns of activity shown in the neural recordings, Kilgard and Engineer believed they could predict the rats’ ability to discriminate the speech sounds. They hypothesized that speech sounds that generate similar patterns of neural activity would be impossible for the brain, and thus the rat, to tell apart. In contrast, speech sounds that generate dissimilar patterns would be easy for rats to tell apart.

To test their theory, they trained rats to press a lever in response to some speech sounds and not others. Although rats can’t talk and certainly don’t have language, the new study reveals that rats can easily hear the difference between most speech sounds. The auditory system in rats and many other animals are surprisingly similar to humans’.

For example, the neural responses for the words dad and sad are very different. (See video.) As expected, rats can easily distinguish between these two words. The neural responses for the words rad and lad are very similar. Not surprisingly, rats, like many children, find it very difficult to differentiate between these two words.

The neural patterns explain the rats’ ability to differentiate between different speech sounds. “Our study is the first to tie the perception of speech sounds to the neural response of the same sounds,” said Engineer.

So, they’ve cracked the code, now what? The implications are huge. The perception of speech sounds is important because these are the acoustic building blocks of language. Scientists couldn’t begin to isolate the problems with speech and hearing disorders until they understood how speech sounds are normally processed in the brain.

Already, one of the most cited researchers in the world on neuroplasticity, the brain’s ability to change, Kilgard has big plans for his UT Dallas students and lab. He not only tackles ambitious topics in neuroscience, but in the process, he creates hands-on opportunities for his students at every level to get involved. This is what inspired Engineer to pursue her Ph.D.

“Dr. Kilgard encourages undergraduates to follow their interests. They have the rare opportunity to initiate and run their own projects and publish in prestigious journals. If it weren’t for these opportunities, I wouldn’t have gone on to graduate school,” said Engineer. She has worked with Kilgard since 2003, as an undergraduate, and expects to complete her Ph.D in August.

The emphasis on student involvement is illustrated by the number and diversity of the authors listed on the Nature Neuroscience study. Engineer and Kilgard’s research team included master’s students Claudia Perez and Helen Chen; undergraduates Ryan Carraway and Kevin Chang; and Ph.D. students Amanda Reed, Jai Shetake and Vikram Jakkamsetti.

“This paper in Nature Neuroscience is a great testimony to the level of graduate education students receive at UT Dallas. Dr. Kilgard is a wonderful mentor who helps students develop into independent researchers,” said Dr. Bert Moore, dean of the School of Behavioral and Brain Sciences. “We are proud of both Crystal and Mike for this exciting research.”

Source: University of Texas at Dallas, TX
http://www.utdallas.edu/news/2008/04/23-001.php

The kiwi classroom of the future could look a little like this, if American educationalist Dr Leonard Sax has any influence.

A room is filled with 7-year-old boys, none of whom is sitting - in fact there are no chairs on offer.

There is noise, cooler light and the temperature has been turned down. This, says Sax, is the environment in which boys learn best.

The Maryland-based executive director of the National Association for Single Sex Public Education, is in New Zealand next month to speak at several single sex schools including Auckland’s St Cuthbert’s College and Dilworth School, and at Iona College, Lindisfarne College and Woodford House, Hawke’s Bay.

Citing research from Harvard Medical School, the US National Institute of Health and various European studies, Sax argues that no one-size-fits-all education programme can be successfully applied across the sex divide, that both girls and boys will flourish in environments tailored to their gender-specific requirements.

Traditional arguments for sex-segregated schools are often based broadly on the management of teenage hormones. The theory was there would be less distraction for everyone if the girls and boys were educated separately. But hormones have no part in today’s rationale for single-sex classes.

“There’s been a pretty fundamental shift in the way people think about single-sex education, at least in North America, over the last 20 years or so,” says Sax. “That’s what’s new: the idea that the single-sex format may be most beneficial for children who are 5, 6, 7 years old. This is the empirical finding.”

Of the 367 public schools in the US that have adopted the single-sex format in the past few years, Sax says that all but about 20 are primary schools.

“[I’m] not saying that there are not benefits at the high school level; there certainly are. But the benefits in the early primary years are much greater.”

He says advanced imaging techniques have offered neuroscientists fresh insights into brain development.

“When you compare a six-year-old girl with a six-year-old boy, you find quite staggering differences in the brain,” says Sax.

Regions of the brain develop in a different sequence in the genders, he says.

The areas of the brain associated with language and fine motor skills mature about six years earlier in girls than boys. The areas of the brain associated with maths and geometry mature about four years earlier in boys than girls. This finding may help explain why some girls find maths “hard”, he says, while some boys think poetry is for “sissies”.

According to Sax, understanding and exploiting these nuances allow educators to adapt lessons and classrooms to suit the all-girl or all-boy population.

One “very reliable difference” between 6-year-old boys and 6-year-old girls is in their ability to sit still and be quiet. The average girl can sit still for longer than the average boy, with implications for the duration of lessons and the structure of the day, says Sax. Girls can have longer, uninterrupted classes, but boys will do best with 20-minute lessons followed by a run around outside.

Some US schools have taken this finding a step further. At both Cunningham School for Excellence, Iowa, and Foley Intermediate, Alabama, sitting is optional in the all-boys classes. And Chicago’s Hardey Prep doesn’t even supply chairs to their 6 and 7-year-old boys.

“As one teacher said to me: when that boy sits down his brain shuts off,” says Sax. “So the boys stand for many of the classes.

“In the mixed classroom, every choice you make is going to advantage the girls at the expense of boys or advantage the boys at the expense of girls,” he says. “The lack of awareness of gender differences often has the unintended consequence of disadvantaging both the girls and the boys.”

But Sax’s theories relate not only to the type of lesson, but to the environment the students work best in.

He says studies of young people of normal weight have shown that the ideal room temperature for boys to learn is about 20C; for girls it’s about 3 degrees higher. With classroom thermostats typically set at somewhere between 21C and 22C, Sax says that both genders will be outside their ideal comfort zone.

Evidence that tailoring the learning experience rather than simply splitting up boys and girls enhances academic performance is mounting, with research showing improved grades and test results in both sexes.

Sax advocates the introduction of single-sex classes into co-ed schools as some New Zealand schools are already doing. In Auckland’s Mt Albert Grammar, most of the junior classes are gender segregated while Long Bay College in Auckland last year introduced single-sex classes.

Sax says he wasn’t always a devotee of single-sex education, believing that “we live in a co-ed world… schools should prepare kids for the real world”. And there are still many critics of the single-sex education model, notably the American Civil Liberties Union and the National Organisation for Women, who see it as a discriminatory anachronism. Under the old model that prevailed in the US until around the 1960s, boys’ schools typically received the bulk of the resources while girls’ schools made do with their leftovers and hand-me-downs.

But Sax has no intention of returning to what he describes as “the bad old days”. He was educated in an era when “they pushed girls and boys into pink and blue cubby holes” - boys had compulsory woodwork, girls had home economics. The new world order he favours aims to “expand educational horizons, to get more girls excited about computer science and physics and engineering - and to get more boys excited about art and poetry and creative writing and foreign languages“.

“The irony is that we’ve had roughly three decades throughout the English-speaking world of ignoring gender, pretending that gender doesn’t matter,” he says.

“There are substantially fewer young women studying computer science, physics and engineering than there were 20 years ago - and fewer men who regard creative writing, or writing at all, as something that boys do. So we’ve ignored gender and the result of ignoring gender has been not to eliminate gender stereotypes; it has been a hardening of gender stereotypes.”

New Zealand Herald, New Zealand
http://www.nzherald.co.nz/category/story.cfm?c_id=35&objectid=10505122

Why people continue to blame vaccines, despite evidence to the contrary.

As the brother of an autistic person and a brain scientist, I have been hoping that the increased focus on autism in the news would lead to a greater public understanding of this disorder. Instead, I am angry that this coverage is spreading dangerous myths.

My sister, Karen, is autistic. In the 1970s, my parents wondered why she behaved so differently. At the time, a prevalent idea was that an emotionally distant mother could somehow prevent a child from understanding emotions or relating normally to others. Our parents had a simpler idea, that they might have hurt Karen’s head during a bath.

Both these ideas are wrong. Autism is a neurological disorder, and its signs appear by the age of 1 or even earlier. It is highly inheritable. In identical twins where one is autistic, the chance that both are autistic is greater than 50-50. Even non-identical twins and siblings are at increased risk. In short, I dodged a genetic bullet. Now I worry about my daughter.

A link that isn’t there

Recently, celebrities such as Jenny McCarthy and other activists have taken to the airwaves to repeat the myth that autism is linked to vaccination. Although peer-reviewed scientific evidence overwhelmingly opposes their views, they have attracted attention. In a recent discussion on Larry King Live, three pediatricians invited to make the case for science were no match for McCarthy’s star power. Situations like this could mistakenly persuade parents to leave their children unvaccinated and vulnerable to contagious diseases.

Speculation about a vaccine-autism link began with a 1998 uncontrolled study of a few autistic children. But the conclusions were later retracted. Subsequent speculation focused on the compound thimerosal. But removing it from all routine childhood vaccines in the USA, Denmark, Sweden and Canada has not decreased autism rates.

What are McCarthy’s credentials? She is an actress and comedienne — with an autistic son. Her career took on new life after she wrote a best-selling pregnancy guide. Like all parents of autistic children, she wrestled with the question of what caused his disorder. She recalled that her son was vaccinated about the time his symptoms first appeared. Aha! That’s it. Here is an example of her reasoning: “I believe that parents’ anecdotal information is science-based information.”

How we’re wired

Although her concept of evidence is flawed, I don’t blame her. The error highlights how our brains are wired to think. Like the authors of the 1998 study, she concluded that two events happening around the same time must be linked. They used the principle that coincidence implies a causal link. But there was no coincidence for her son: He was born in 2002, after thimerosal was removed from vaccines.

The problem is compounded by “source amnesia,” in which people are prone to remember a statement without recalling where they heard it or whether the source was reliable. Presidential candidate John McCain might have fallen prey to source amnesia when he repeated the vaccine-autism myth last month. Recollection is more likely when the “fact” fits previously held views; parents might already dislike vaccinations based on their kids’ reaction to shots. But when it comes to a complex issue such as autism, such errors of reasoning hinder us from distinguishing real causes from coincidences.

Out of sight of the cameras, increased research funding is spurring efforts to find autism’s causes. Scientists are vitally interested in possible environmental influences. But the vaccine story is a dry well. Working on it further wastes valuable time and resources. It’s time to dig elsewhere.

As I watch my beautiful 10-month-old daughter grow, I wish that preventing autism were as simple as withholding a few injections. But along with my wife, a physician, I understand the vital importance of vaccination, not only for maintaining our baby’s health but also protecting our community from infectious diseases. Our daughter’s next shots are in two months.

Sam Wang is an associate professor of molecular biology and neuroscience at Princeton University. He is a co-author of Welcome to Your Brain: Why You Lose Your Car Keys But Never Forget How to Drive and Other Puzzles of Everyday Life.

Source: USA Today
http://blogs.usatoday.com/oped/2008/04/autism-myth-liv.html

A new project to study the brains of people with autism in unprecedented detail could finally pinpoint subtle neurological changes that underlie the disorder. Researchers will use an innovative set of tools developed to study gene expression to analyze exactly where early brain development goes awry.

“The technology now exists to be able to examine in fine detail the organization of brain cells–for example, whether brain cells have their proper number and position,” says Eric Courchesne, a neuroscientist at the University of California, San Diego, who is leading the project. “This could provide a major insight into the cause of autism.”

Autism is a neurodevelopmental disorder characterized by deficits in language and social behavior. While the brains of people with autism appear broadly normal, previous brain-imaging studies have revealed unusual growth patterns in very young children with the disorder. “It’s clear that in the first two years of life, the brain grows too large, too fast,” says Courchesne.

Scientists don’t yet understand the reason for the strange growth spurt–whether it’s caused by too many neurons in a particular part of the brain or a failure to prune extraneous neurons, a common occurrence in normal development. They hope that an unusual set of tools developed for the Allen Brain Atlas, a database of gene expression in the mouse brain, could finally yield clues.

To create the map, researchers at the Allen Institute for Brain Science in Seattle, WA, painstakingly created a comprehensive set of DNA probes that highlight the expression patterns of individual genes. While previous studies have only been able to look at the expression of a handful of genes at a time, these probes can provide a wealth of information by revealing the expression of many genes simultaneously.

Researchers at the Allen Institute have been sifting through the toolbox for probes that can identify different cell types in the human cortex–the most recently evolved part of the brain. The team will use them to study the expression of approximately 25 genes in samples of postmortem brain tissue collected from very young children with autism. “This will give us a much clearer look at how things are disorganized, rather than just saying they are disorganized,” says Ed Lein, director of neuroscience at the Allen Institute.

The researchers will focus on the prefrontal cortex, an area in the frontal lobes involved in higher-order social and emotional communication, and one of the brain regions most affected by abnormal early overgrowth. The DNA probes will allow researchers to compare the location and organization of specific cell types, such as excitatory neurons that connect to brain areas outside of the cortex and inhibitory neurons that form local cortical circuits.

“It’s fundamentally important to identify the cause of that overgrowth,” says Courchesne. “It may help us understand how best to tailor interventions for autism, not just behaviorally, but for medical and chemical interventions down the road.”

The project will be the first to use the tools developed at the Allen Institute to study the neurobiology of human disease. The data will be made publicly available via the Web for other scientists to study, as data from the mouse brain study is now.

Source: MIT Technology Review, MA
http://www.technologyreview.com/Biotech/20557/

A study of a research team of the State Key Laboratory of Brain and Cognitive Sciences, The University of Hong Kong (HKU), demonstrated for the first time that brains of dyslexics differ in readers of different languages.

The study, which compared dyslexic children who are readers of Chinese to those of English, indicated structural and functional differences between both groups. The findings implied that dyslexia may be different neurological conditions in readers of different languages. This research may help tailor-making therapies for children who grow up in different cultures.

The work “A structural-functional basis for dyslexia in the cortex of Chinese readers” by Dr Siok Wai Ting and her colleagues in HKU was published in April 2008 in the Proceedings of the National Academy of Sciences (PNAS) of the United States of America, a prestigious international multi-disciplinary scientific journal. Dr Siok is Principal Investigator of the State Key Laboratory and Assistant Professor of Linguistics.

Developmental dyslexia affects 7% to 9% of children in Hong Kong, and up to 17% throughout the world. It results in a severe learning disability in acquiring reading skills.

Previous neuroimaging studies have revealed that dyslexic readers of alphabetic languages like English have decreased gray-matter volume in posterior brain systems, and have weak reading-related activity in the left temporoparietal and occipitotemporal regions of the brain.

In order to assess whether these abnormalities were universal, or culture-dependent, Dr Siok said her team had been studying dyslexic Chinese children. She explained that while alphabetic languages like English were learnt using letter-to-sound conversion rules, pronunciations in a non-alphabetic language like written Chinese, which is composed of square-shaped or picture-like characters, must be memorized by rote.

In this latest study, the team used two brain imaging techniques.

Firstly, voxel-based morphometry, an established whole-brain gray-matter assessment technique, was used to analyze the high-resolution 3D anatomical images acquired with magnetic resonance images (MRIs) from 16 Chinese dyslexic subjects and 16 age-matched normal children as controls. The children, who were studying in Beijing primary schools, were all native speakers of Putonghua, on average aged 11, and all strongly right-handed.

It was found that the gray-matter volume in the left middle frontal gyrus region, which is important for the coordination of cognitive resources in working memory and previously has been shown to play a role in Chinese reading and writing, was significantly smaller in dyslexic children than in normal subjects. But at the same time, their more posterior brain systems remained unaffected. Previous studies have revealed that dyslexic English readers have decreased gray-matter volume in their posterior regions.

Secondly, a functional MRI experiment was conducted on a subset of 12 of each of the dyslexics and control groups. They were asked to decide whether two Chinese characters viewed simultaneously rhymed with each other. The rhyme judgment task involves phonological processing which would reflect in activation of some regions in the brain. It was found that the normal subjects had much stronger activation of the left middle frontal gyrus region during the task than the dyslexic group. The dyslexic Chinese readers demonstrated little activation in the posterior brain regions related to reading-related activity in English readers.

The fact that Chinese and Western dyslexics show structural abnormalities in different brain regions suggests that dyslexia may even be two different brain disorders in the two streams of culture.

“What causes brain structure abnormalities for dyslexia is currently unknown. Previous genetic studies suggest that malformations of brain development are associated with mutations of several genes and that developmental dyslexia has a genetic basis. Our brain imaging findings may well provide useful clues for further genetic studies in dyslexia,” said HKU’s Professor of Linguistics Tan Li-Hai, who is also Principal Investigator of the State Key Laboratory.

Dr Siok, lead author of the study, said the study would certainly help in the development of more efficient tests for early identification of Chinese children with reading disabilities, and more effective strategies to remediate dyslexia, tailored made for Chinese.

Dr Siok explained that the left middle frontal gyrus is responsible for working memory and is spatially close to the motor cortex, whereas the left posterior brain areas are involved in letter-to-sound mappings and are spatially close to the auditory cortex. “Our findings suggest that educational intervention for Chinese dyslexia may involve working memory and sensorimotor tasks. Current treatments of English dyslexia already use the aspects of letter-sound conversions and phonological awareness“, she said. (…)

Source: ScienceBlog.com, CA
http://tinyurl.com/5v8wpr

Uncover how the brains of infants distinguish differences in sounds and it may become possible to correct language problems even before children start to speak, sparing them the difficulties that come from struggling with language.

New studies conducted by Professor of Neuroscience April Benasich and her Infancy Studies Laboratory at Rutgers University in Newark are revealing new and exciting clues about how infant brains begin to acquire language and paving the way for correcting language difficulties at a time when the brain is most able to change.

Benasich and her lab were the first to determine that how efficiently a baby processes differences between rapidly occurring sounds is the best predictor of future language problems. Using methods developed by Benasich and her lab, it can be determined as early as three to six months whether a baby will struggle with language development.

Benasich’s research is now focused on uncovering in specific detail how the developing brain processes and distinguishes acoustic differences that arrive in rapid succession. The ability to differentiate those sounds, such as the difference between “ba” and “da,” is critically important because decoding language requires us to process tiny auditory differences occurring as quickly as 40 milliseconds. During the first months of life, the baby’s developing brain also is involved in constructing an acoustic map of the sounds of his or her native language. That map allows the baby to efficiently acquire language. Apparently, however, in some infants the process seems to go awry.

About 5 to 10 percent of all children beginning school are estimated to have language-learning impairments (LLI) leading to reading, speaking and comprehension problems, according to Benasich. In families with a history of LLI, 40 to 50 percent of children are likely to have a similar problem. Many of these children go on to develop dyslexia.

Using several novel methods, including dense array EEG/ERP recordings, Benasich and her lab are able to analyze EEG, ERPs and the proportion of gamma power in infant brains. The dense sensor array allows the researchers to gently measure a full range of brain activity. Those measurements are obtained by placing a soft bonnet of sensors, resembling a hairnet with lots of little sponges, on a baby’s head and then having the infant listen to different series of rapid tone sequences.

“We are finding that children who have difficulty processing rapid auditory input are not just showing a simple maturational lag, but are actually processing incoming acoustic information differently,” says Benasich.

Specifically, the research shows that babies who struggle with rapid auditory processing appear to be using different brain areas (as shown by neural patterns) and perhaps different analysis strategies to accomplish that task than children who do not have such difficulties. Included among their initial findings, the researchers have found less left hemisphere activity in the brains of children who struggle with rapid auditory processing as compared with matched control children. By pinpointing the exact differences in how the brain handles incoming acoustic information, it may become possible to guide the brains of babies at risk of developing language problems to work more efficiently before the children even begin to speak.

“We can predict with about 90 percent accuracy what a baby’s language capabilities will be just by their response to tones,” says Benasich. “Our hope now is that we will be able to gently guide the brains of infants who are at the highest risk for language learning impairments to be more efficient processors so they can avoid the difficulties that result from struggling with language.”

To shed additional light on how inefficiencies in rapid auditory processing might be corrected, Benasich and her team have developed a Magnetic Resonance Imaging (MRI) protocol for scanning naturally sleeping healthy babies. This technique will allow better localization of active brain areas. To solve the challenge of imaging the brains of young children who typically are unable to lie still for extended periods in a scanner, Benasich’s team conducts the scans in the evening and asks the parents to go through their child’s normal bedtime routine, such as reading their infant a story, nursing them, rocking and snuggling. Once the child is asleep, headphones providing a steady stream of lullabies and an acoustic foam bonnet are placed on the baby’s head to reduce the sound of the MRI.

“Our goal is not only to develop training techniques to correct rapid auditory processing problems, but to identify the period during infant development when the brain is most “plastic,” or most able to change through learning,” explains Benasich.

The lab’s work is funded by several sources, including grants from the Solomon Center for Neurodevelopmental Research, the Don and Linda Carter Foundation, the National Institute of Child Health and Human Development, and a new $460,000 grant from the Ellison Medical Foundation.

Source: Science Daily
http://www.sciencedaily.com/releases/2008/04/080410153652.htm

They are age-old questions, from the moment of birth: What’s your baby thinking? How much does your child really understand?

“They’re not just wailing away. There’s something going on that’s important to their development, right from the very beginning,” said speech professor Patricia Kuhl of the University of Washington.

Researchers at the UW are now using baby caps that can detect the most minute electrical current being sent out by a baby’s brain.

Little Isabella is listening to a very unusual audio tape.

To most adults the syllables all sound alike, but in fact they are just slightly different. Believe it or not, Isabella, who isn’t even yet talking, can tell the difference and her brain waves prove it.

“Their brains are set automatically to capture this information in ways that are completely surprising,” said Kuhl.

Kuhl and her husband, psychology professor Andy Meltzoff, are two of the world’s top scientists in the growing field of early learning.

Their research has shown up in every major magazine. Their book, The Scientist in the Crib, is now published in French, German, Chinese - more than 10 languages in all.

Several years ago, they started the Institute for Learning and Brain Sciences, bringing together 50 scientists at the UW, studying both the brain and behavior, and discovering that babies understand far more than parents or scientists ever thought possible.

“Babies learn more in the first three years of life than we ever will again,” said Dr. Meltzoff.

What we know is they learn by copying us. In a very simple experiment, Dr. Meltzoff stuck out his tongue and found that even a two-week-old baby knows how to imitate.

“It shows that they’re born learning. Really, babies are born learning,” he said.

Perhaps more remarkable is what Dr. Meltzoff discovered with slightly older babies. If you show them how to play with a toy, even if you don’t let them imitate immediately, they will save it in their brain. They’ll imitate you when you give them the toy - up to four months later, demonstrating that babies have incredible memory.

“Often times, the parents would say, oh I know I’ve seen that toy before, but I can’t remember what to do with it. And the baby would do the right thing,” said Dr. Meltzoff.

“That’s what’s different about the brain of a baby,” said Dr. Kuhl.

Meanwhile, Dr. Kuhl has spent years focusing on language. What struck her is that all mothers have a special way of talking to a baby.

Kuhl calls it “motherese,” or “parentese,” because dads do it naturally too.

Why do we talk that way? Are babies getting anything out of it?

It turns out they are.

“The vowels, if you measure ee, ah and ooh, in words like sheep and shoe and keys, they’re much more distinct in motherese. They’re further apart acoustically. It’s like being able to show a baby, here’s what to listen for. Here are the components,” said Dr. Kuhl.

She discovered that babies learn about language long before they utter their first word.

In a speech lab, she took 9-month-old babies and exposed them to a second language, either Spanish or Mandarin. And after just 12 sessions over one month, the babies could detect subtle phonetic sounds in the foreign language.

“The babies in the United States, exposed in that way, are as good as the babies in Taiwan for example, at hearing the Chinese distinctions,” said Dr. Kuhl.

Isabella was exposed to Spanish for a month, which is why she now distinguishes sounds that most English-only speakers cannot.

In another lab, Dr. Meltzoff is studying the crucial moment when a baby learns not just to look at mom, but to follow where mom’s eyes are focused.

He said 10-month-old babies, who are good at following where an adult is gazing, had about twice as many words in their speech eight months later.

“So when she’s around in the living room and says, ‘here’s a rattle, look at the rattle,’ the babies need to know to follow where she’s looking and that’s what the word refers to,” he said.

All these studies suggest that babies are learning an incredible amount that first year, and yet scientists cannot explain why we as adults have no specific memories of our time as babies.

We’re tempted to think maybe there isn’t that much going on in their brains, but Kuhl and Meltzoff say it’s just the opposite, that babies absorb culture, language, social interaction, emotions - the most basic building blocks of who they’ll become some day.

“The news is that babies are even learning from their peers at day-care centers, and learning from us so we’re role models right from the beginning,” said Dr. Kuhl.

“It is lasting learning. It’s the kind of learning that makes a profound effect on the baby’s brain and mental operations, and that sets them up for later.”

Source: KING5.com, WA
http://tinyurl.com/6a7zh6