Brain imaging technology shows how the adult dyslexic brain can change

Nov 1 2004

New findings from researchers at Georgetown University Medical Center in collaboration with Wake Forest University School of Medicine have shown that there is hope for individuals suffering a life-long history of reading problems.

Using brain imaging technology the research group showed how the adult dyslexic brain responds to a specific phonological-based reading intervention program responsible for reading skill improvement.

Published in the October 28 issue of the Journal Neuron, this is the first research study to examine the brain systems related to successful phonological-based instruction in dyslexic adults.

“Reading is one of the most important skills we learn – it affects virtually every aspect of a person’s life,” said Dr. Guinevere Eden, associate professor of pediatrics, director of Georgetown University’s Center for the Study of Learning, and lead author of the study. “Despite the fact that the majority of individuals with dyslexia are adults, little is known about the biological basis of how they can improve their reading skills. We need to understand the neural mechanisms behind these research-based reading instructions so that we can achieve a deeper understanding of precisely how these interventions work. Our findings suggest that the brain mechanisms used by adult dyslexics might be different from those observed when young children undergo remediation, a strong indication that there will never be a ‘one size fits all’ approach to helping dyslexics become proficient readers.”

Using functional magnetic resonance imaging (fMRI), nineteen dyslexic adults underwent brain imaging twice. Half of the group completed an eight-week, phonological intervention program between the two scans, with the rest of the dyslexics serving as a comparison group.

During the consecutive testing sessions researchers evaluated the participants’ reading and phonological skills (i.e., the ability to sound out words by correctly associating sounds with written symbols). Phonological skills are critical for learning to read and often found to be impaired in individuals with developmental dyslexia. Eden notes that this type of rigorous clinical trial design is not practiced as often in reading research as it is in traditional medical research.

Participants in this study showed strong improvement in their phonological and reading accuracy skills following the intervention. One participant had never read a book before in her life; following the study she read before work every day, setting her alarm clock early to do so.

In addition, their brain scans revealed activity changes in specific regions. In addition to activity customarily seen in the left hemisphere of typical readers, the dyslexic participants’ brains surprisingly showed activity in the right hemisphere as well, acting as a way to compensate for deficiencies they may have in regions that are activated in typical readers. The brain scans also showed that recovery mechanisms, usually seen in pediatric dyslexia cases, are also working in adults brains. This suggests that unlike children learning to read, adult brains change in different ways with compensation and recovery working in concert.

“People in this study showed us that it may never be too late for adults who want to improve their reading skills,” said Dr. Lynn Flowers from Wake Forest University, the senior author who has followed this cohort of dyslexics since the 1980s. “At the tail end of Dyslexia Awareness Month, the important take away message from our study is that there is significant hope for adults who have been unable to read for years. Ideally we can identify dyslexia at the outset and intervene early to help children academically and emotionally. But, we now know that there are effective ways to address adult dyslexia as well.”

“Work like this can provide important information to develop new research-based teaching programs that can ultimately help other adults to become proficient readers,” said G. Reid Lyon, PhD, Chief, Child Development & Behavior Branch, National Institute of Child Health & Human Services National Institutes of Health, Bethesda, M.D. “This is an exciting area of research in which scientists converge with educators to achieve the common goal of helping individuals with dyslexia achieve the reading skills they need to succeed in life.”

This research was funded by the National Institutes of Health. In addition to researchers mentioned in this release, this research was conducted by the following colleagues: Karen Jones, Katherine Cappell, Lynn Gareau, Dr. Thomas Zeffiro, Nichole Dietz and Dr. John Agnew, from Georgetown, and Dr. Frank Wood, from Wake Forest University.