Vanderauwera, J. 1 , Vandermosten, M. 1 , Theys, C. 2 , Sunaert, S. 2 , Wouters, J. 3 & Ghesquière, P. 1
1 Parenting and Special Education, Faculty of Psychology and Educational Sciences, KU Leuven
2 Translational MRI, Department of Imaging and Pathology, KU Leuven
3 ExpORL, Department of Neurosciences, KU Leuven
It is generally accepted that the reading problems in persons with dyslexia are caused by a deficit in the development and the use of phonological representations. However, little is known about how the neural reading network develops, especially in relation to dyslexia. Previous fMRI studies demonstrate that persons with dyslexia fail to produce the typical pattern of widespread left lateralised activation that reading elicits. Given that these regions are distant, examination of their connections is vital to understand the causes of underactivation. In the current longitudinal study the neural connections of reading-related areas in pre-reading children (last year of kindergarten) and in beginning readers (2th grade) will be examined using two neuroimaging techniques: DTI (indicating structural connectivity) and Resting-state fMRI (indicating functional connectivity). We scanned 40 pre-reading children with a family risk for dyslexia and 35 control children. The high-risk group (HR) consists of children with at least one first-degree relative with a formal dyslexia diagnosis. The control group (LR) is individually matched based on age, gender, nonverbal intelligence and educational environment. Also cognitive data were collected, including pre-reading phonological and orthographic skills. At the moment of the conference, DTI-data of the first (pre-reading) wave will be analyzed. The bilateral arcuate fasciculus (AF) and the left inferior fronto-occipital fasciculus (IFOF) will be delineated. We will be able to make conclusions on whether (1) in line with our previous adult study (Vandermosten et al., Brain, 2012) relations of fractional anisotropy (FA) in AF with phonology and in IFOF with orthography can be replicated in preschoolers, and whether (2) a white matter deficit in left AF can be found for the children at risk for dyslexia. This study strives to contribute to the discovery of specific neurophysiologic markers for dyslexia, important for the early detection of this specific learning ability.