0000000000005139
AUTHOR
Sanne Van Der Mark
Reading for meaning in dyslexic and young children : distinct neural pathways but common endpoints
Developmental dyslexia is a highly prevalent and specific disorder of reading acquisition characterised by impaired reading fluency and comprehension. We have previously identified fMRI- and ERP-based neural markers of impaired sentence reading in dyslexia that indicated both deviant basic word processing and deviant semantic incongruency processing. However, it remained unclear how specific these impairments are for dyslexia, as they occurred when children with dyslexia (DYS) were compared to chronological age-matched controls (CA) who also differ in the amount of reading experience. Adding a younger control group at a similar reading level (RL) as the dyslexic group, we examined here whic…
Children with dyslexia lack multiple specializations along the visual word-form (VWF) system.
Developmental dyslexia has been associated with a dysfunction of a brain region in the left inferior occipitotemporal cortex, called the "visual word-form area" (VWFA). In adult normal readers, the VWFA is specialized for print processing and sensitive to the orthographic familiarity of letter strings. However, it is still unclear whether these two levels of occipitotemporal specialization are affected in developmental dyslexia. Specifically, we investigated whether (a) these two levels of specialization are impaired in dyslexic children with only a few years of reading experience and (b) whether this impairment is confined to the left inferior occipitotemporal VWFA, or extends to adjacent …
Predictors of developmental dyslexia in European orthographies with varying complexity
Background: The relationship between phoneme awareness, rapid automatized naming (RAN), verbal short-term/working memory (ST/WM) and diagnostic category is investigated in control and dyslexic children, and the extent to which this depends on orthographic complexity. Methods: General cognitive, phonological and literacy skills were tested in 1,138 control and 1,114 dyslexic children speaking six different languages spanning a large range of orthographic complexity (Finnish, Hungarian, German, Dutch, French, English). Results: Phoneme deletion and RAN were strong concurrent predictors of developmental dyslexia, while verbal ST/WM and general verbal abilities played a comparatively minor role…
Neurophysiology in preschool improves behavioral prediction of reading ability throughout primary school.
BACKGROUND: More struggling readers could profit from additional help at the beginning of reading acquisition if dyslexia prediction were more successful. Currently, prediction is based only on behavioral assessment of early phonological processing deficits associated with dyslexia, but it might be improved by adding brain-based measures. METHODS: In a 5-year longitudinal study of children with (n = 21) and without (n = 23) familial risk for dyslexia, we tested whether neurophysiological measures of automatic phoneme and tone deviance processing obtained in kindergarten would improve prediction of reading over behavioral measures alone. RESULTS: Together, neurophysiological and behavioral m…
Cognitive mechanisms underlying reading and spelling development in five European orthographies
This paper addresses the question whether the cognitive underpinnings of reading and spelling are universal or language/orthography-specific. We analyzed concurrent predictions of phonological processing (awareness and memory) and rapid automatized naming (RAN) for literacy development in a
Impaired semantic processing during sentence reading in children with dyslexia: combined fMRI and ERP evidence
Developmental dyslexia is a specific disorder of reading acquisition characterized by a phonological core deficit. Sentence reading is also impaired in dyslexic readers, but whether semantic processing deficits contribute is unclear. Combining spatially and temporally sensitive neuroimaging techniques to focus on semantic processing can provide a more comprehensive characterization of sentence reading in dyslexia. We recorded brain activity from 52 children (16 with dyslexia, 31 controls) with functional magnetic resonance imaging (fMRI) and event-related potentials (ERP) in two separate counterbalanced sessions. The children silently read and occasionally judged simple sentences with seman…
The left occipitotemporal system in reading: disruption of focal fMRI connectivity to left inferior frontal and inferior parietal language areas in children with dyslexia.
Developmental dyslexia is a severe reading disorder, which is characterized by dysfluent reading and impaired automaticity of visual word processing. Adults with dyslexia show functional deficits in several brain regions including the so-called "Visual Word Form Area" (VWFA), which is implicated in visual word processing and located within the larger left occipitotemporal VWF-System. The present study examines functional connections of the left occipitotemporal VWF-System with other major language areas in children with dyslexia. Functional connectivity MRI was used to assess connectivity of the VWF-System in 18 children with dyslexia and 24 age-matched controls (age 9.7-12.5 years) using f…
Genetic analysis of dyslexia candidate genes in the European cross-linguistic NeuroDys cohort
The work conducted at the WTCHG was supported by Wellcome Trust grants [076566/Z/05/Z] and [075491/Z/04]; the work in Zurich partly by an SNSF grant [32-108130]. We also thank MAF (Mutation Analysis core Facility) at the Karolinska Institute, Novum, Huddinge. The French part of the project was funded by Agence Nationale de la Recherche (ANR-06-NEURO-019-01 GENEDYS) and Ville de Paris. S Paracchini is a Royal Society University Research Fellow. D Czamara was supported by the Deutsche Forschungsgemeinschaft (German Research Foundation) within the framework of the Munich Cluster for Systems Neurology (EXC 1010 SyNergy). Dyslexia is one of the most common childhood disorders with a prevalence o…