MECANISMOS DE IDENTIFICACIÓN DE PALABRAS EN NIÑOS DISLÉXICOS EN ESPAÑOL: ¿EXISTEN SUBTIPOS? MECHANISMS OF WORD IDENTIFICATION IN DYSLEXIC CHILDREN IN SPANISH DYSLEXIC CHILDREN: DO SUBTYPES EXIST?

Utilizando un test de lectura de frases para evaluar el nivel de eficiencia lectora de escolares de 3o a 6o de educacion primaria, fueron seleccionados 60 ninos con mas de dos anos de retraso especifico en lectura (dislexicos) y 65 normolectores (control edad). El objetivo era establecer la existencia de un deficit del mecanismo de lectura fonologico (evaluado con lectura de pseudopalabras) y consecuentemente, del mecanismo lexico-ortografico (evaluado con escritura de palabras inconsistentes). Se utilizo el analisis de regresion para poner en evidencia subtipos de dislexicos caracterizados por puntajes desequilibrados entre las dos medidas. Los resultados globales muestran deficits importantes a nivel fonologico y ortografico. La clasificacion en subtipos senala una mayoria de dislexicos “armonicos” y “de superficie” sin aparecer claramente el subtipo “fonologico”. La proporcion de armonicos aumenta con el nivel escolar y alcanza el 90% del grupo de dislexicos en 6° ano. Los resultados son interpretados en el marco del modelo de autoensenanza. La ausencia de dislexicos fonologicos es interpretada considerando que estos casos aparecen tipicamente en sistemas ortograficos opacos en los cuales el mecanismo de ensamblado fonologico es poco fiable, lo que induce a la memorizacion de imagenes ortograficas de las palabras.  Abstract The reading effi ciency level of primary education children at 3rd to 6th grade was assessed using a phrase reading test. Two groups were selected: dyslexics (n=60), which presented more than 2 years of specifi c reading retardation, and a control group (n=65) of age-equivalent normal readers. The aim of the study was to establish the existence of a defi cit in the phonological processing mechanism (evaluated with a pseudo-word reading task) and, consequently, in the lexical-orthographic mechanism  (evaluated with an inconsistent word spelling task). Dyslexic subtypes were detected by using the regression method, characterised by the fact that the score in one of the tasks was not correctly predicted by the score in the other. The global results indicate a substantial defi cit in both phonological and orthographic tasks. Classifi cation into subgroups showed that most dyslexics belonged to either “harmonic” or “surface” categories. No children could be clearly characterized as “phonological” dyslexics. The proportion of harmonic dyslexics increased with the school grade and reached 90% in 6th grade. The results are discussed in the framework of the self-teaching model. The absence of phonological dyslexics was explained by considering that these cases appear consistently in opaque orthographic systems, in which phonological coding is not reliable, and which would lead readers to memorize orthographic representations of words.