Remediation Training Improves Reading Ability of Dyslexic Children - By: Lisa Trei

For the first time, researchers have shown that the brains of dyslexic children can be rewired -- after undergoing intensive remediation training -- to function more like those found in normal readers.

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The training program, which is designed to help dyslexics understand rapidly changing sounds that are the building blocks of language, helped the participants become better readers after just eight weeks.

The findings were released Monday in "Neural deficits in children with dyslexia ameliorated by behavioral remediation: Evidence from functional MRI," published by the Proceedings of the National Academy of Sciences Early Edition.

"It was very dramatic to see the huge differences that occurred in the brains of these children," said Stanford psychology Professor John Gabrieli, one of the study's authors. "The intervention, although substantial, only covered eight weeks. One note of optimism about the study is that such a limited intervention can have a substantial effect on reading scores."

Brain imaging scans of the children who participated in the training showed that critical areas of the brain used for reading were activated for the first time, and that they began to function more normally. Furthermore, additional regions of the brain were activated in what the researchers believe the dyslexics may have used as a compensatory process as they learned to read more fluently.

Gabrieli said the study's findings may help demonstrate how different kinds of reading programs can tackle various problems faced by poor readers. "This is showing us for the first time the specific changes in the brains of children receiving this sort of treatment, and how that is coupled with the improvement they have in reading and language ability," he said. "We're hoping that this becomes an additional tool to understand how educational remediation programs alter children's abilities, as they must do, by changing the way their brains process information."

Study co-author Paula Tallal, professor of neuroscience at Rutgers University and a founder of Scientific Learning Corporation, the Oakland-based company that designed the program, said the findings are also important because it is the first time a commercial product has been proven scientifically to work using standardized educational testing and brain imaging. Scientific Learning's computer program, Fast ForWord Language, focuses on helping children become more fluent at processing the rapidly changing sounds, she said.

"In light of President [George W.] Bush's legislation, No Child Left Behind, which mandates that only scientifically validated applications be used for intervening with children, this program has the potential to address the crisis we are facing in the number of children failing to meet [educational] standards," she said. The No Child Left Behind Act of 2001 places an emphasis on teaching methods that have been proven scientifically to work.

Dyslexia, sometimes called "word blindness," is a common disorder, affecting 5 to 10 percent of Americans, Gabrieli said. It is defined as a specific difficulty in reading that is severe enough to interfere with academic functioning and cannot be accounted for by lack of educational opportunities, personal motivation or problems in sight or sound. Tallal said that studies estimate that about 40 percent of people with dyslexia inherit it genetically. Other factors believed to trigger the disorder include prematurity at birth, developmental language impairment and attention deficits, she said.

Dyslexics have trouble distinguishing between letters that rhyme, such as 'B' and 'D.' "If you hear the sound 'ba' in butter and 'da' in Doug, the only way we know the difference is in the first 40 milliseconds of the onset of those sounds," Tallal explained. "The ability to extract the sounds out of words is what is called phonological awareness. We have to be aware that words can be broken into sounds, called phonemes, and that these sounds have to be identified with letters." This process might appear intuitive, but it is a learned skill, Tallal said.

The training program the children took part in was targeted at helping them learn to process and interpret the very rapid sequence of sounds within words and sentences by exaggerating and slowing them down. "These are the building blocks you have to have in place before you can learn to read," Tallal said. "I think Fast ForWord is building the scaffold for reading, and doing it based on scientific knowledge of the most efficient and effective way of helping the brain learn."

The study

The study included 20 dyslexic children aged 8 to 12 years. Their brains were scanned using functional magnetic resonance imaging (fMRI) at Stanford's Lucas Center for Magnetic Resonance Spectroscopy before and after participating in the eight-week training program. A control group of 12 children with normal reading abilities also had their brains scanned but did not participate in the training.

The scanning machines, which look like beds that slide into small tubes, normally are used to check for brain injuries or tumors, Gabrieli said. With slightly different software they can be used to measure which regions of the brain are active by looking for changes in blood oxygenation, a process that occurs in parts of the brain where the neurons are active.

Study lead author Elise Temple, assistant professor in human development at Cornell, headed the research as a graduate student at Stanford. Both the dyslexic children and the control group were asked to perform a simple rhyming task while having their brains scanned. Participants were shown two uppercase letters and told to push a button if the two letters rhymed with each other. For example, 'B' and 'D' would match, but not 'B' and 'K.'

Twenty-minute sessions were broken into five-minute segments, during which the children had to stay completely still. Afterward, they were rewarded with Pokémon or baseball cards, and given a picture of their brain to take home. Before the sessions started, Temple allowed the children to play around the machines, which can be claustrophobic, to help them become comfortable with the testing process. "In this study, it was especially important not to have the experience be a bad one because we wanted them to come back," Temple said.

During the rhyming exercise, children with normal reading showed activity in both the language-critical left frontal and temporal regions of the brain, the latter of which is behind and above the left ear. Dyslexics, however, struggled with the task and failed to activate the temporal region, and showed some activity only in the frontal brain area.

Afterward, the dyslexic children used the Fast ForWord Language computer program for 100 minutes a day, five days a week, as part of their regular school day. "The computer games were fun, the kids liked them," Gabrieli said. The program consisted of seven exercises that rewarded players when they answered questions correctly. For example, when a picture of a boy and a toy was shown, a voice from the computer would ask the player to point to the boy, a step that required understanding the very brief difference in the sound of the first consonant in each word. Initially, the questions were asked in a slower, more exaggerated fashion than in normal speech to help the children understand the sounds inside the words. As the player progressed, the speed of the voice in the program slowly increased. "Each child worked at his or her own level," Tallal said. "The goal was to leave all children processing sounds correctly in words and sentences of increasing length and grammatical complexity."

The results

Following the training, the dyslexic children's scores went up in a number of language and reading tests, Gabrieli said. "The study supported the idea that for some children, getting training on just simply processing rapid sounds is a route to becoming much more fluent and capable readers," he said. In addition, activation of the children's brains fundamentally changed, becoming much more like that of good readers. "We see that the brains of these children are remarkably plastic and adaptive, and it makes us hopeful that the best language intervention programs in the future can alter the brains in fundamentally helpful ways," he said.

It is likely that the children will continue to need considerable help in reading, Gabrieli said. "This is not a one-shot vaccine," he said. "But it makes them much more prepared to take advantage of a regular curriculum to read successfully and do well."

The next step, Temple said, is to see if other commercial programs can alter the brain as well. "I don't know if these changes are unique to this program," she said. "Are there some training programs that are better for some kids than others?" A future goal would be to offer a series of tests to help select which programs best meet a child's needs, she said.

For many years, Gabrieli said, the nation has been concerned with the best methods to teach reading. "We're hoping that this becomes one piece of many pieces of research that will help us better understand ... what are effective ways to rescue children who have trouble reading," he said. In addition, the study brings the scientific use of brain imaging into the arena of education. "We'd like to use these cutting-edge tools of neuroscience to somehow directly assist thoughts about educational curricula, policies and ways to help children perform better in school and look forward to better futures," he said.

In addition to Temple, Tallal and Gabrieli, the paper was written by Gayle K. Deutsch, a senior clinical scientist at Stanford; Russell Poldrack, a former postdoctoral student at Stanford and currently assistant professor of psychology at the University of California-Los Angeles; Steven L. Miller of Scientific Learning Corporation; and Michael M. Merzenich, a founder of Scientific Learning and a professor at the University of California-San Francisco. The Haan Foundation for Children helped fund the study.

This article was originally published in the Stanford Report on February 25, 2003.

The Brain’s Gardeners

Microglia (green) with purple representing the P2Y12 receptor which the study shows is a critical regulator in the process of pruning connections between nerve cells.

 A new study out today in the journal Nature Communications shows that cells normally associated with protecting the brain from infection and injury also play an important role in rewiring the connections between nerve cells.  While this discovery sheds new light on the mechanics of neuroplasticity, it could also help explain diseases like autism spectrum disorders, schizophrenia, and dementia, which may arise when this process breaks down and connections between brain cells are not formed or removed correctly.

“We have long considered the reorganization of the brain’s network of connections as solely the domain of neurons,” said Ania Majewska, Ph.D., an associate professor in the Department of Neuroscience at the University of Rochester Medical Center (URMC) and senior author of the study.  “These findings show that a precisely choreographed interaction between multiple cells types is necessary to carry out the formation and destruction of connections that allow proper signaling in the brain.”

The study is another example of a dramatic shift in scientists’ understanding of the role that the immune system, specifically cells called microglia, plays in maintaining brain function.  Microglia have been long understood to be the sentinels of the central nervous system, patrolling the brain and spinal cord and springing into action to stamp out infections or gobble up dead cell tissue.  However, scientists are now beginning to appreciate that, in addition to serving as the brain’s first line of defense, these cells also have a nurturing side, particularly as it relates to the connections between neurons.

The formation and removal of the physical connections between neurons is a critical part of maintaining a healthy brain and the process of creating new pathways and networks among brain cells enables us to absorb, learn, and memorize new information.  

“The brain’s network of connections is like a garden,” said Rebecca Lowery, a graduate student in Majewska’s lab and co-author of the study.  “Not only does it require nourishment and a healthy environment, but every once in a while you need to prune dead branches and pull up weeds in order to allow new flowers to grow.”

While this constant reorganization of neural networks – called neuroplasticity – has been well understood for some time, the basic mechanisms by which connections between brain cells are made and broken has eluded scientists. 

Performing experiments in mice, the researchers employed a well-established model of measuring neuroplasticity by observing how cells reorganize their connections when visual information received by the brain is reduced from two eyes to one. 

The researchers found that in the mice’s brains microglia responded rapidly to changes in neuronal activity as the brain adapted to processing information from only one eye.  They observed that the microglia targeted the synaptic cleft – the business end of the connection that transmits signals between neurons.  The microglia “pulled up” the appropriate connections, physically disconnecting one neuron from another, while leaving other important connections intact. 

This is similar to what occurs during an infection or injury, in which microglia are activated, quickly navigate towards the injured site, and remove dead or diseased tissue while leaving healthy tissue untouched. 

The researchers also pinpointed one of the key molecular mechanisms in this process and observed that when a single receptor – called P2Y12 – was turned off the microglia ceased removing the connections between neurons.

These findings may provide new insight into disorders that are the characterized by sensory or cognitive dysfunction, such as autism spectrum disorders, schizophrenia, and dementia.  It is possible that when the microglia’s synapse pruning function is interrupted or when the cells mistakenly remove the wrong connections – perhaps due to genetic factors or because the cells are too occupied elsewhere fighting an infection or injury – the result is impaired signaling between brain cells.

“These findings demonstrate that microglia are a dynamic and integral component of the complex machinery that allows neurons to reorganize their connections in the healthy mature brain,” said Grayson Sipe, a graduate student in Majewska’s lab and co-author of the study.  “While more work needs to be done to fully understand this process, this study may help us understand how genetics or disruption of the immune system contributes to neurological disorders.”

Additional co-authors include Emily Kelly and Cassandra Lamantia with URMC and Marie Eve Tremblay with Laval University in Quebec.  The study was support by the National Eye Institute and the National Institute for Neurological Disorders and Stroke.

Can We Predict Future Literacy Skills in Children? - Hallie Smith, MA CCC-SLP

Study: Predicting literacy skills in children years before they read

A new study says non-reading children as young as age 3 carry objective neurophysiological markers that signal whether they will struggle to read. Children so young have never been tested before, but the research team found a way to measure their brain responses to sound, a key part of pre-reading development.

The groundbreaking study found promising results in how to predict reading abilitybefore reading instruction begins. More testing is needed, but if the approach works, scientists may literally predict if a toddler is at risk. That could lead to early intervention strategies that dramatically improve a child’s reading skills, said senior researcher and neurobiologist Nina Kraus, director of Northwestern’s Auditory Neuroscience Laboratory, Evanston, Ill.

“If you know you have a 3-year-old at risk, you can, as soon as possible, begin to enrich their life in sound so that you don’t lose those crucial early developmental years,” Kraus told The Huffington Post.

The study published in the July issue of PLOS Biology is one of the first to find that the brain’s ability to process the sounds of consonants in noise is critical for language and reading development. In other words, reading begins with the ears, not the eyes, as our brains index meaningful sounds and attempt to block out noise, all within microseconds.

“This is arguably some of the most complex computation that we ask our brain to do,” Kraus told National Public Radio.

Noisy environments tax all of us when we’re trying to listen for meaningful sound, according to Martha Burns, Ph.D., Joint Appointment Professor at Northwestern University. But for children with auditory processing disorders (APD), meaningful sounds sound, well, simply muddled. And classrooms can be very noisy places, where children with APD may find it difficult to filter out irrelevant noise.

“The child’s natural instinct, just like yours, is to stop listening. As a result, children with APD often achieve way under their potential despite being very bright,” Burns wrote.

Researchers have already found ways to help children with auditory processing disorders. Burns notes, for example, that programs such as Fast ForWord Language v2 can change the brainstem response to speech and improve auditory processing skills, helping children improve their ability to listen for competing words and deciphering words that are unclear.

But noise, as distinct from sound, particularly affects the brain’s ability to hear consonants. Consonants are said very quickly and not as loudly or as long as vowels - which in contrast - are acoustically simple.

The methodology: how did the study work?

Kraus and her team used a combination of consonants and vowels, specifically the sound “da,” to see how well kids’ brains could filter out background noise. The results showed tremendous potential for identifying children with potential reading problems later in life. “Our results suggest that the precision and stability of coding consonants in noise parallels emergent literacy skills across a broad spectrum of competencies – all before explicit reading instruction begins,” the study says.  

Here’s how Kraus’s team discovered the neurological markers in youngsters too young to read. In a series of experiments, they asked 112 kids between the ages of 3 and 14 to choose a favorite movie and sit in a comfortable chair. Then, researchers attached electroencephalograms (EEGs) to each of the children’s scalps to monitor their brain waves while they listened to a video soundtrack in one ear and to noise in the other ear. The transmitted noise, specifically the sound “da,” was imposed over background chatting of about a half dozen people.

The EEG output to a computer allowed Kraus’s team to actually see the kids’ brain waves and understand how well they could separate the sound “da” from the noisy chatter. The brain should respond the same way repeatedly to the sound “da,” Kraus said. But if the brain doesn’t respond the same way over and over again, something may be wrong with the child’s auditory processing. “If the brain responds differently to that same sound - (even though) the sound hasn’t changed – how is a child to learn?” Kraus said.

The team tested the 3-year-olds, then re-tested them the following year. In the follow-up, researchers learned they could predict which of the 4-year-olds would struggle with reading. They also tested children as old as 14 and found that they could predict reading skills and learning disabilities.

What are the implications?

Based on the results, researchers developed a model to predict reading performance. The test is a “biological looking glass into a child’s literacy potential,” Kraus told NPR.

“If the brain’s response to sound isn’t optimal, it can’t keep up with the fast, difficult computations required to process in noise,” she said. “Sound is a powerful, invisible force that is central to human communication. Everyday listening experiences bootstrap language development by cluing children in on which sounds are meaningful. If a child can’t make meaning of these sounds through the background noise, he won’t develop the linguistic resources needed when reading instruction begins.”

The findings have far-reaching consequences for parents and educators because, clearly, they show that reading is about perceiving sound. To reiterate, reading is about the ears, not the eyes.

And, when it comes to reading intervention, the earlier, the better.

“My vision for this is to have every child tested at birth,” Kraus said.

For further reading:

It Could Be Possible To Predict Which Kids Will Struggle With Reading, Says Study

Auditory Processing in Noise:  A Preschool Biomarker for Literacy

Detecting Reading Problems in Preschoolers

Interview with Nina Kraus, PhD, Auditory Neuroscience Laboratory, Northwestern University

The Test That Can Look Into A Child's (Reading) Future