Brain Imaging Reveals Remedial Instruction Can Make Stronger Readers

Just as a regimented workout routine helps human muscles become stronger and perform better, specialized exercise for the brain can enhance cognitive skills, according to researchers.

A new brain imaging study conducted by Carnegie Mellon University (Pittsburgh, PA, USA) researchers of persons with poor reading skills demonstrated that 100 hours of remedial instruction, similar to reading "calisthenics,” set to help in problem areas, not only improved the abilities of struggling readers, but also altered the way their brains activated when they understood the written sentences. This was the first brain imaging study in which children were tested on their comprehension of sentences, not just on their recognition of single words.

The results may pave the way to a new era of neuroeducation. According to the Carnegie Mellon researchers, those with poor reading skills initially have less activation in the parietotemporal area of the brain than do persons with good reading skills. The parietotemporal area is responsible for decoding the sounds of written language and assembling them into words and phrases that constitute a sentence. However, remedial instruction increases the struggling readers' activation to near normal levels.

This also was the first brain imaging study in which children were tested on their understanding of the meanings of sentences, not just on their recognition of single words.
"This study demonstrates how the plasticity of the human brain can work for the benefit of remedial learning,” stated neuroscientist Dr. Marcel Just, director of Carnegie Mellon's Center for Cognitive Brain Imaging (CCBI), and senior author of the new study currently available on the website of the journal Neuropsychologia. "We are at the beginning of a new era of neuroeducation.”

Persons with poor reading skills worked in groups of three for an hour each day with a teacher specialized in administering a remedial reading program. The training included both word decoding exercises in which students were asked to recognize the word in its written form and tasks in using reading comprehension strategies. Those with poor reading skills were 25 fifth-graders taken from a stratified sample from schools in Allegheny County, home to Pittsburgh and a number of its surrounding municipalities.

Utilizing functional magnetic resonance imaging (fMRI), CCBI research fellows Ann Meyler and Tim Keller measured blood flow to all of the different parts of the brain while children were reading and found that that the parietotemporal areas were significantly less activated among those with poor reading skills than in the control group. The sound-based representation that is constructed in the parietal areas is then processed for the meanings of the words and the structure of the sentence, activating other brain areas.

The sentences were comparatively straightforward ones, which the children assessed as being sensible or nonsense, such as "The girl closed the gate” and "The man fed the dress.” The children's accurate sensibility judgments ensured that they were actually processing the meaning of the sentences, and not just recognizing the individual words.

Furthermore, the activation increases in the previously underactivating areas remained evident well after the intensive instruction had ended. When the children's brains were scanned one year after instruction, their neural gains were not only maintained but also had become better established.

"With the right kind of intensive instruction, the brain can begin to permanently rewire itself and overcome reading deficits, even if it can't entirely eliminate them,” Dr. Just said.

These findings of initial parietotemporal underactivation among persons with poor reading skills provide evidence against a common misconception about dyslexia. There is a persistent but incorrect belief that dyslexia is mostly caused by difficulties in the visual perception of letters, leading to confusions between letters like ‘p' and ‘d.' However, such visual difficulties are the cause of dyslexia in only approximately 10% of the cases. The most common cause, accounting for more than 70% of dyslexia, is a difficulty in relating the visual form of a letter to its sound, which is not a straightforward process in the English language. The same parietotemporal areas of the brain that showed increased activation following instruction are centrally involved in this sound-based processing.


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