title: Learning to read improves the structure of the arcuate fasciculus.
abstract: The acquisition of literacy results from an effortful learning process that leads to functional changes in several cortical regions. We explored whether learning to read also leads to anatomical changes within the left intrahemispheric white matter pathways that interconnect these regions. Using diffusion tensor imaging tractography, we compared illiterates with ex-illiterates who learned to read during adulthood and literates who learned to read during their childhood. Literacy related to an increase in fractional anisotropy and a decrease in perpendicular diffusivity in the temporo-parietal portion of the left arcuate fasciculus. The microstructure within this pathway correlated with the reading performance and the degree of functional activation within 2 dominant brain regions involved in reading: The Visual Word Form Area in response to letter strings, and the posterior superior temporal cortex in response to spoken language. Thus, the acquisition of literacy is associated with a reinforcement of left temporo-parietal connections whose microstructure predicts overall reading performance and the functional specialization of the Visual Word Form Area. This anatomical magnetic resonance imaging marker may be useful to predict developmental reading disorders.
authors.affiliation: Natbrainlab, Department of Forensic and Neurodevelopmental Sciences, Institute of Psychiatry, King's College London, London, UK.
authors.forename: Michel
authors.initials: M
authors.lastname: Thiebaut de Schotten
authors.forename: Laurent
authors.initials: L
authors.lastname: Cohen
authors.forename: Eduardo
authors.initials: E
authors.lastname: Amemiya
authors.forename: Lucia W
authors.initials: LW
authors.lastname: Braga
authors.forename: Stanislas
authors.initials: S
authors.lastname: Dehaene
mesh_terms: D001111:Arcuate Nucleus of Hypothalamus / Q000098:blood supply / Q000502:physiology*; D001931:Brain Mapping; D056324:Diffusion Tensor Imaging; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D007858:Learning / Q000502:physiology*; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009413:Nerve Fibers, Myelinated / Q000473:pathology; D009415:Nerve Net / Q000473:pathology; D010100:Oxygen / Q000097:blood; D011932:Reading
chemical_list: D010100:Oxygen