The reading network in dyslexia

Developmental dyslexia is a common reading disorder, affecting 5-15% of the population that negatively impacts a child's ability to achieve literacy. Because the developing brain is so plastic, there are substantial changes that occur as a result of skil l development, which can confound attempts to distinguish cause from effect. Thus, there is a need for longitudinal studies of children who are at-risk for developing dyslexia. However, in countries like the UK and USA, there is a cultural philosophy th at children are never too young to start learning how to read, which leads to children being exposed to print at variable and often very young ages. Scanning children below the age of 5 is particularly difficult because they move around a lot. In Norway and other Scandinavian countries, however, the educational ideology of pre-school is focused more on play, and teaching literacy is left to the schools. Therefore, children who are 6 years old have not been exposed to print very much. While scanning 6- year-olds comes with its own set of difficulties, they are considerably less than in younger children. Dr. Hugdahl's group, which is located at the University of Bergen, has a very unique ongoing longitudinal study on the risk factors for dyslexia. Twent y-six children who were determined to be at-risk for dyslexia and twenty-six age- and gender-matched controls who were determined to have low risk for developing dyslexia were enrolled in the study. The first timepoint was collected when the children wer e 6 years old, before they had started formal literacy training. The study is currently in its third wave of data acquisition, when the subjects are age 12, and have been formally diagnosed with dyslexia. The study proposed here combines sophisticated m ethods for integrating multimodal neuroimaging data with a powerful experimental design to gain a better understanding of the neurobiological bases of dyslexia.