Poor readers' use of orthographic information in reading, memory and phonological tasks

This thesis examined the abilities of 10-12 year old poor readers and reading age controls in phonological processing, printed word learning, reading and memory based tasks. It was found that the poor readers showed little impairment in carrying out phonological segmentation of spoken words, though there was more marked impairment with nonwords. Nonword reading was found to be slower than that of controls and poor readers also demonstrated a tendency to provide letter names rather than sounds in a phoneme identification task. In a study of learning new print vocabulary it was found that the poor readers were slower than controls to learn to read the set of nonwords accurately, and had poorer auditory memory for the items. However, they were much better at identifying these items in a visual recognition task. They also showed a less marked regularity effect and were more influenced by the visual appearance of words in an auditory rhyme judgement task. In a study of their working memories, the poor readers showed a visual bias in their memory codes for serial recall of pictorial stimuli, i.e. they showed no word length effect, a phonemic similarity effect of reduced magnitude, and a visual similarity effect. This indicated the use of a visual strategy to remember pictures, rather than the verbal coding preferred by the controls. When words were presented auditorily or in print form, however, the poor readers showed normal phonemic similarity and word length effects. It was concluded that poor readers rely on visual information where the presented images are highly codable, and verbal recoding is not obligatory, but that they will make use of phonological coding when the stimuli are not easily codable visually in memory. The results of these investigations suggest that these poor readers' visual and verbal coding systems might be poorly linked. Thus, when learning to read new words poor readers might prefer to use visual coding. Accordingly, poor readers may rely on intact visual processes because they need to compensate for inefficient or poorly connected visual and verbal systems, rather than because they have inefficient phonological processing skills as such