Caffarra, S. 1 , Martin, C. 1, 2 , Likarazu, M. 1 , Lallier, M. 1 , Zarraga, A. 1 , Molinaro, N. 1, 2 & Carreiras, M. . 1, 2
1 Basque Center on Cognition, Brain and Language, Spain
2 Ikerbasque, Basque Foundation for Science, Spain
Studies on illiterate adults suggest that reading-induced brain changes might be massive and not limited to linguistic processes. The present study investigates literacy impact on children?s linguistic and non-linguistic brain mechanisms in order to identify to which extent neural responses are reorganized while children learn to read.
An MEG experiment was conducted on two groups of Basque children (skilled and less-skilled readers, 4-8y) while they were passively viewing written words and objects. The evoked fields of the experimental stimuli were compared to their scrambled counterparts. Visual words elicited left posterior (200-300ms) and fronto-temporal (400-800ms) activations in skilled readers only. Brain responses to objects were greater than scrambles in posterior regions (200-500ms), with skilled readers showing stronger left-lateralization than less-skilled readers. Correlation values suggest that as reading performance improved, brain responses to objects were greater in left posterior sites. Our results provide evidence that literacy not only influences written word processing in children, but also affects visual object recognition, suggesting a non-language specific impact of reading on children?s neural dynamics. The present findings seem to suggest that literacy allows the left hemisphere language network to be activated by visual objects.