Affiliations: Inserm, Imagerie cérébrale et handicaps
neurologiques UMR 825, Toulouse, France | E.A Octogone. Laboratoire Jacques-Lordat, E.A 4156,
Université Toulouse II Le Mirail, Toulouse, France | Universite de Toulouse; UPS; Imagerie
cérébrale et handicaps neurologiques UMR 825; CHU Purpan, Toulouse
Cedex 9, France | Centre Hospitalier Universitaire de Toulouse, Pole
Neurosciences, CHU Purpan, Toulouse Cedex 9, France
Note: [] Corresponding author: Mélanie Jucla, Laboratoire
Octogone-Lordat, Université de Toulouse le Mirail, Pavillon de la
recherche, 5, allées Antonio Machado, F-31058 Toulouse Cedex, France. Tel.: +33 561502469
Abstract: This study aimed at investigating the ERP correlates (N170 and P300
components) of a multimodal training program focused in dyslexia. ERPs were
obtained from 32 electrodes in 24 French children with developmental dyslexia
(mean age 10 years 7 months) during a visual lexical decision task. All the
children received two intensive two-month evidence-based training programs: one
based on phonemic awareness and the other on visual and orthographic processing
in a cross-over design. Ten control children matched on chronological age were
also tested. We showed dissociation between N170, P300 and behavioral
improvement. In the dyslexic group, P300 amplitude decreased for non-words and
words as the latter yielded performance improvement. In the control group, the
same effect was observed for pseudo-words. At the same time, the opposite
pattern occurred for the N170 latency, which was shortened for pseudo-words and
pseudo-homophones in the dyslexic group and for words in the typically
achieving children. We argue that training might modulate cortical activity in
dyslexic children in a visual word recognition task. Considering the well-known
implication of P300 in attentional processes, our results reflect the strong
link between reading skill improvement after remediation and visual attentional
process maturation.
