The study, published online in , is among the first to identify structural white matter and functional gray matter differences in the brain between children with dyslexia and dysgraphia, and between those children and typical language learners. The researchers say the findings underscore the need to provide instruction tailored to each of these specific learning disabilities, though that is currently not mandated under federal or state law.

“This shows that there’s a brain basis for these different disabilities,” said co-author , a psychologist who heads the 91̽»¨Learning Disabilities Center, funded by the National Institute of Child Health and Human Development. “So they require different diagnoses, and different instruction. We’ve got to start acknowledging this.”

The study involved 40 children in grades 4 to 9, including 17 diagnosed with dyslexia — persisting difficulty with word reading and spelling — and 14 diagnosed with dysgraphia, persisting difficulty with handwriting, along with 9 typical language learners. The children were asked to write the next letter in the alphabet following a letter they were shown, to write the missing letter in a word spelling, to rest without any task, and to plan a text about astronauts.

The children used a developed at the 91̽»¨that allowed researchers to record their writing in real time while their active brain connections were measured with functional magnetic resonance imaging, or fMRI.

The three groups differed from each other in written language and cognitive tasks. The control group had more connections, which facilitate functional connections in for language processing and cognitive thinking. By contrast, children with dyslexia and dysgraphia showed less white matter connections and more functional connections to gray matter locations — in other words, their brains had to work harder to accomplish the same tasks.

“Their brains were less efficient for language processing,” said lead author , a 91̽»¨professor of radiology.

The results, Berninger said, show that the two specific learning disabilities are not the same because the white matter connections and patterns and number of gray matter functional connections were not the same in the children with dyslexia and dysgraphia — on either the writing or cognitive thinking tasks.

Federal law guarantees a free and appropriate public education to children with learning disabilities, but does not require that specific types of learning disabilities are diagnosed, or that schools provide evidence-based instruction for dyslexia or dysgraphia. Consequently, the two conditions are lumped together under a general category for learning disabilities, Berninger said, and many schools do not recognize them or offer specialized instruction for either one

“There’s just this umbrella category of learning disability,” said Berninger. “That’s like saying if you’re sick you qualify to see a doctor, but without specifying what kind of illness you have, can the doctor prescribe appropriate treatment?”

“Many children struggle in school because their specific learning disabilities are not identified and they are not provided appropriate instruction,” Berninger said. Recent published in February in Computers & Education shows that computerized instruction has tremendous potential to help time-strapped teachers in regular classrooms provide such instruction for children with dyslexia and dysgraphia, but only if they are correctly diagnosed.

“Dyslexia and dysgraphia are not the only kinds of learning disabilities. One in five students in the United States may have some kind of a specific learning disability,” Berninger said. “We just can’t afford to put 20 percent of children in special education classes. There just aren’t the dollars.”

Other co-authors are , director of the 91̽»¨Integrated Brain Imaging Center; , a 91̽»¨senior fellow in radiology; 91̽»¨research scientists Katie Askren, Paul Robinson and Kevin Yagle; 91̽»¨undergraduate students Desiree Gulliford, Zoe Mestre and Olivia Welker; and William Nagy, a professor of education at Seattle Pacific University.

The device and research using it to study the brain patterns of children will be presented June 18 at the meeting in Seattle. A , developed by the UW’s , was , 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 , 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 91̽»¨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 , professor of radiology and principal investigator of the 91̽»¨. “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.”

The work was supported by a grant from the National Institutes of Health. Other 91̽»¨collaborators on the project are Peter Boord, Mary Askren and Virginia Berninger.

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For more information, contact Reitz at freitz@uw.edu, or 206-543-9023.