Posts tagged learning disabilities
Articles and news from the latest research reports.
Fiber-optic pen helps see inside brains of children with learning disabilities
For less than $100, University of Washington researchers have designed a computer-interfaced drawing pad that helps scientists see inside the brains of children with learning disabilities while they read and write.
The device and research using it to study the brain patterns of children will be presented June 18 at the Organization for Human Brain Mapping meeting in Seattle. A paper describing the tool, developed by the UW’s Center on Human Development and Disability, was published this spring in Sensors, an online open-access journal. “Scientists needed a tool that allows them to see in real time what a person is writing while the scanning is going on in the brain,” said Thomas Lewis, director of the center’s Instrument Development Laboratory. “We knew that fiber optics were an appropriate tool. The question was, how can you use a fiber-optic device to track handwriting?”
To create the system, Lewis and fellow engineers Frederick Reitz and Kelvin Wu hollowed out a ballpoint pen and inserted two optical fibers that connect to a light-tight box in an adjacent control room where the pen’s movement is recorded. They also created a simple wooden square pad to hold a piece of paper printed with continuously varying color gradients. The custom pen and pad allow researchers to record handwriting during functional magnetic resonance imaging, or fMRI, to assess behavior and brain function at the same time.Other researchers have developed fMRI-compatible writing devices, but “I think it does something similar for a tenth of the cost,” Reitz said of the UW system. By using supplies already found in most labs (such as a computer), the rest of the supplies – pen, fiber optics, wooden pad and printed paper – cost less than $100.The device connects to a computer with software that records every aspect of the handwriting, from stroke order to speed, hesitations and liftoffs. Understanding how these physical patterns correlate with a child’s brain patterns can help scientists understand the neural connections involved.
Researchers studied 11- and 14-year-olds with either dyslexia or dysgraphia, a handwriting and letter-processing disorder, as well as children without learning disabilities. Subjects looked at printed directions on a screen while their heads were inside the fMRI scanner. The pen and pad were on a foam pad on their laps.
Subjects were given four-minute blocks of reading and writing tasks. Then they were asked to simply think about writing an essay (they later wrote the essay when not using the fMRI). Just thinking about writing caused many of the same brain responses as actual writing would.
“If you picture yourself writing a letter, there’s a part of the brain that lights up as if you’re writing the letter,” said Todd Richards, professor of radiology and principal investigator of the UW Integrated Brain Imaging Center. “When you imagine yourself writing, it’s almost as if you’re actually writing, minus the motion problems.”
Richards and his staff are just starting to analyze the data they’ve collected from about three dozen subjects, but they have already found some surprising results.
“There are certain centers and neural pathways that we didn’t necessarily expect” to be activated, Richards said. “There are language pathways that are very well known. Then there are other motor pathways that allow you to move your hands. But how it all connects to the hand and motion is still being understood.”
Besides learning disorders, the inexpensive pen and pad also could help researchers study diseases in adults, especially conditions that cause motor control problems, such as stroke, multiple sclerosis and Parkinson’s disease.
“There are several diseases where you cannot move your hand in a smooth way or you’re completely paralyzed,” Richards said. “The beauty is it’s all getting recorded with every stroke, and this device would help us to study these neurological diseases.”
Learning disabilities affect up to 10 percent of children
Up to 10 per cent of the population are affected by specific learning disabilities (SLDs), such as dyslexia, dyscalculia and autism, translating to 2 or 3 pupils in every classroom according to a new study.
The study – by academics at UCL and Goldsmiths - also indicates that children are frequently affected by more than one learning disability.
The research, published in Science, helps to clarify the underlying causes of learning disabilities and the best way to tailor individual teaching and learning for affected individuals and education professionals.
Specific learning disabilities arise from atypical brain development with complicated genetic and environmental causes, causing such conditions as dyslexia, dyscalculia, attention-deficit/hyperactivity disorder, autism spectrum disorder and specific language impairment.
While these conditions in isolation already provide a challenge for educators, an additional problem is that specific learning disabilities also co-occur for more often that would be expected. As, for example, in children with attention-deficit/hyperactivity disorder, 33 to 45 per cent also suffer from dyslexia and 11 per cent from dyscalculia.
Lead author Professor Brian Butterworth (UCL Institute of Cognitive Neuroscience) said: “We now know that there are many disorders of neurological development that can give rise to learning disabilities, even in children of normal or even high intelligence, and that crucially these disabilities can also co-occur far more often that you’d expect based on their prevalence.
"We are also finally beginning to find effective ways to help learners with one or more SLDs, and although the majority of learners can usually adapt to the one-size-fits-all approach of whole class teaching, those with SLDs will need specialised support tailored to their unique combination of disabilities."
As part of the study, Professor Butterworth and Dr Yulia Kovas (Goldsmiths) have summarised what is currently known about SLD’s neural and genetic basis to help clarify what is causing these disabilities to develop, helping to improve teaching for individual learners, and also training for school psychologists, clinicians and teachers.
What the team hope is that by developing an understanding of how individual differences in brain development interact with formal education, and also adapting learning pathways to individual needs, those with specific learning disabilities will produce more tailored education for such learners.
Professor Butterworth said: “Each child has a unique cognitive and genetic profile, and the educational system should be able to monitor and adapt to the learner’s current repertoire of skills and knowledge.
"A promising approach involves the development of technology-enhanced learning applications – such as games - that are capable of adapting to individual needs for each of the basic disciplines."
(Source: eurekalert.org)
Is there a link between childhood obesity and ADHD, learning disabilities?
A University of Illinois study has established a possible link between high-fat diets and such childhood brain-based conditions as attention deficit hyperactivity disorder (ADHD) and memory-dependent learning disabilities.
“We found that a high-fat diet rapidly affected dopamine metabolism in the brains of juvenile mice, triggering anxious behaviors and learning deficiencies. Interestingly, when methylphenidate (Ritalin) was administered, the learning and memory problems went away,” said Gregory Freund, a professor in the U of I College of Medicine and a member of the university’s Division of Nutritional Sciences.
The research was published in Psychoneuroendocrinology.
Freund said that altered dopamine signaling in the brain is common to both ADHD and the overweight or obese state. “And an increase in the number of dopamine metabolites is associated with anxiety behaviors in children,” he added.
Intrigued by the recent upsurge in both child obesity and adverse childhood psychological conditions, including impulsivity, depression, and ADHD, Freund’s team examined the short-term effects of a high-fat (60% calories from fat) versus a low-fat (10% calories from fat) diet on the behavior of two groups of four-week-old mice. A typical Western diet contains from 35 to 45 percent fat, he said.
“After only one week of the high-fat diet, even before we were able to see any weight gain, the behavior of the mice in the first group began to change,” he said.
Evidence of anxiety included increased burrowing and wheel running as well a reluctance to explore open spaces. The mice also developed learning and memory deficits, including decreased ability to negotiate a maze and impaired object recognition.
Switching mice from a high-fat to a low-fat diet restored memory in one week, he noted.
In mice that continued on the high-fat diet, impaired object recognition remained three weeks after the onset of symptoms. But Freund knows from other studies that brain biochemistry normalizes after 10 weeks as the body appears to compensate for the diet. At that point, brain dopamine has returned to normal, and mice have become obese and developed diabetes.
“Although the mice grow out of these anxious behaviors and learning deficiencies, the study suggests to me that a high-fat diet could trigger anxiety and memory disorders in a child who is genetically or environmentally susceptible to them,” he said.
Because the animals adapt to the high-fat fare, the scientists also hypothesized that abruptly removing fat from the diet might negatively affect anxiety, learning, and memory.
The researchers had expected that the high-fat diet would stimulate inflammation, which is associated with obesity, but they saw no evidence of an inflammatory response in the brain after one or three weeks on the high-fat regimen.
Instead, they saw evidence that a high-fat diet initiates chemical responses that are similar to the ones seen in addiction, with dopamine, the chemical important to the addict’s pleasurable experiences, increasing in the brain.
(Source: news.aces.illinois.edu)