Mahé, G. 1 , Bonnefond, A. 2 & Doignon-Camus, N. 2
1 University of Geneva, FPSE, Switzerland
2 University of Strasbourg, INSERM 1114, France
The understanding of the function of the N170 component is of major importance in the investigation of reading disorders, with impaired visual expertise for print reported in dyslexic compared to expert readers. The aim of the present study was to determine if N170 function is limited to a discriminative step between orthographic and non-orthographic visual stimuli (i.e., visual expertise for print) or whether it also reflects an electrophysiological index of fast lexical access. To do so, twenty-eight French-speaking adults performed a lexical decision task in which two factors were manipulated: a) the familiarity of the format in which written strings were displayed (i.e, stimuli displayed horizontally and in a vertical marquee format); and b) reading skills of our participants (i.e., expert and dyslexic adults). Results support the N170 component as a first step of early lexical access as a lexicality effect was only found when fast lexical access was available (i.e., familiar format in expert readers) and not when it was hampered by the unfamiliarity of the display or by impaired reading skills. Moreover, the present findings provide the specificity of the time course of print processing in dyslexia, by comparing parallel and serial processing.