Facteurs cognitifs liés à l'acquisition du lexique orthographique

The objective of the present thesis was to study the relation between cognitive factors (phonological treatment, visuo-attentional and lexical orthographic memory) and the acquisition of implicit and explicit orthographic knowledge.  A longitudinal study was conducted on a sample of 338 children from the kindergarten to their second year of primary schooling.  At the end of kindergarten, the tasks were an invented spelling test and tests assessing the cognitive factors at issue in the apprenticeship of written speech (phonological treatment, visuo-attentional treatment and short and long term memory).   The lexical explicit orthographic knowledge of these same children was evaluated at the end of their first and second year of school. The objective of the first study was to establish a link between the phonological treatment, visuo-attentional and orthographic lexical memory abilities and implicit orthographic knowledge of the children, before their formal apprenticeship of written speech.  The results showed that, contrary to what was long been advanced, the phonological treatment is not the only cognitive factor into play since the long term orthographic lexical memory ability as well as the visuo-attentional ability properly and independently contribute to the acquisition of orthographic knowledge.  The orthographic lexical memory is the factor which provides the strongest contribution.  The aim of the second study was to determine which cognitive factors assessed in kindergarten predict the subsequent explicit orthographic knowledge in first and second grades.   The results showed that the necessary conditions to the acquisition of lexical orthographic knowledge are phonological treatment ability, as well as short and long term memory abilities. The goal of third article was to bring to light the predictive role played by the spelling knowledge of kindergarten children to their orthographical knowledge in first and second grades, in connection with the cognitive abilities which are at the root of the apprenticeship of the written spelling, more particularly the phonological treatment, the visuo-attentional treatment and orthographic lexical memory.   The regressive analyses showed that, among the factors investigated in kindergarten, the implicit orthographical knowledge brings a unique contribution to the subsequent spelling knowledge evaluated by different orthographic tasks in first and second grades.   The important impact of early orthographical knowledge on the subsequent acquisition is not surprising because the first study proved that this knowledge is not only depending on the capability of lexical orthographical memory but also on the capability of phonological treatment. The results coming from those three articles present a non-negligible interest in the understanding of the acquisition of the written speech.  Indeed, these studies permitted to prove that, even before the formal apprenticeship of the writing, the child shows a genuine implicit knowledge of the written language. Moreover, and it is from this knowledge that the subsequent explicit knowledge will be built up.   This knowledge is dependent upon multiple factors among which are the ability of orthographic lexical memory, a cognitive factor whose contribution was not yet proven. The results of this research showed that it is possible to consider early screening measures in order to identify children susceptible to present specific apprenticeship difficulties in the written language.  This screening would allow an early and better targeted intervention, which would then reduce the impact of difficulties on the academic apprenticeships.

Keyphrases: Spelling acquisition, Lexical orthographic knowledge, Lexical spelling, Lexical memory, Invented spelling, Phonological awareness, Visuo-attentional processing