Naming Abilities and Orthographic Recognition during Childhood an Event-Related Brain Potentials Study

Children with reading disabilities or dyslexia, commonly suffer disturbances in phonological awareness, slow-naming speed, and delayed automatic word recognition. A close relation between naming speed and reading difficulties has been well documented; hence, the former could be a useful early predictor of dyslexia. Reading disabled children usually show orthographic problems, but the neurophysiological basis underlying the detection of orthographic violations is still unclear. In this study, 28 healthy, right-handed, second-grade children were selected from a wider screening study and divided into two groups according to their performance on a rapid-naming test battery: slow-naming (SN) and average-naming (AN). Groups were matched by sex, age and school grade, and participants were asked to perform a visual recognition task that consisted of two stimuli: an easily-named drawing followed by a word that either matched (congruent) or did not match (on semantic or orthographic grounds) the drawing. Subjects were instructed to judge the relationship between each pair of stimuli and then press a key on a keyboard while ERP were being recorded. Behavioral results showed significant differences between groups in terms of the number of correct responses, but only for the orthographic violation condition, as no significant differences were observed in reaction times. In addition, SN showed poorer reading performance compared to AN. ERP were significantly different between the two groups during processing of visual words. Results are interpreted as the expression of the difficulties that SN manifested in generating strong associations between phonological and orthographic word forms.