Development of the neurological reading network in children at family risk for dyslexia.

Reading acquisition starts with the awareness that phonemes correspond to graphemes. To achieve stable phoneme-grapheme correspondences, the auditory system must accurately process speech. In developmental dyslexia (a specific learning disability characterized by severe and persistent reading and/or spelling problems), auditory processing and speech perception skills seem already impaired at pre-reading level, identifying these skills as possible behavioural markers for dyslexia. However, little is known about the neural development of the auditory and the reading system in relation to dyslexia. During reading acquisition, the brain adapts to written language by reorganizing and connecting the existing spoken language system into a reading network. It is therefore crucial to examine the neural architecture of important auditory and reading-related areas in pre-reading children, and to investigate how they develop into a more mature reading network. In this new research project, we want to combine the knowledge we acquired in two previous projects: (1) the longitudinal project, investigating the causal relation between auditory processing and reading development on a behavioural level (Boets, et al., 2011), and (2) the neurological project, identifying deviances in the structural connectivity of the reading network (Vandermosten, et al., in press) and in auditory phoneme-level processing (Poelmans, et al., in press) in dyslexic adults. Hence, the current aim is to investigate how the neural determinants of both reading and its underlying cognitive and auditory skills develop prior and throughout reading acquisition and whether dyslexic children show a deviant developmental pattern. Besides data on the family risk of dyslexia and on the longitudinal development of cognitive and auditory skills, we will therefore also assess the neural development by applying three objective neurological techniques (Diffusion Tensor Imaging, Resting-State Functional Connectivity and Auditory Steady-State Responses). To investigate these neural components at different important reading stages, the present project will not only involve a longitudinal part, in which children are followed up from the last year of kindergarten (thus before formal reading instruction) until 3th grade, but also a cross-sectional part, which involves adolescents selected from our longitudinal study started in 2003. Besides theoretical relevance, this project strives to contribute to the discovery of specific neurophysiologic markers for dyslexia, important for the early detection of this specific learning disability.

Keywords:Neurological, Children, Dyslexia

Disciplines:Otorhinolaryngology, Speech, language and hearing sciences, Orthopedagogics and special education