The use of phonological and orthographic information by normal and poor readers of Dutch

In two reading level design experiments, matched groups of normal and poor readers were compared with regard to their use of phonological and orthographic information. Experiment 1 used a semantic decision task similar to the task described in the study of Jarvella & Snodgrass (1974). Experiment 1 was aimed to assess the way normal and poor readers, matched on reading level, automatically process phonological and orthographic incongruencies when comparing the singular and plural of nouns. Experiment 2 investigated the automatized processing of uppercase-lowercase letter incongruencies in a same-different task using words and pseudowords. It assessed the role of letter feature cues involved in the initial identification process. Experiment 1 demonstrated that poor readers needed more time for evaluating phonologically incongruent word pairs. No independent effect of orthographic incongruency was found. Experiment 2 showed that, if compared with reading age matched normals, poor readers had more problems with evaluating uppercase-lowercase incongruencies. This orthographic processing problem was particularly prominent when pseudowords were presented. It is concluded that poor readers not only have phonological processing problems, but also have difficulties at the orthographic processing level.