Visual memory and literacy development
Although auditory memory is usually regarded as being of greatest significance where literacy skills are concerned, there is good evidence that visual memory tasks can also give good indications of dyslexia and literacy difficulties (Awaida and Beech, 1995; Beech, 1997; Singleton, Thomas and Horne, 2000; Bogon et al., 2014). Stuart, Masterson and Dixon (2000) found that visual memory influences the acquisition of sight vocabulary in children aged 5 who displayed poor graphophonic skills (i.e. those who had not yet acquired the ability to segment words on the basis of their sounds and who displayed little or no knowledge of sound-to-letter mappings). For children with good graphophonic skills, however, no association between visual memory and word learning was found. In the CoPS study, the correlations between scores on Letters and single word reading (in the region of 0.28) were clearly not of the order reported by Stuart, Masterson and Dixon. Nevertheless, the results were statistically significant. It should also be borne in mind that in the Stuart, Masterson and Dixon study, the children had to learn to recognise words that were unfamiliar to them (e.g. leopard, haddock, canoe), whereas in the present study, the children were assessed on words that they had already acquired, and no distinction was made between children with good or poor graphophonic skills.
A study by Palmer (2000) found that children who maintained a visual representation of words alongside a phonological representation after age 7, were significantly worse readers than those for whom the ability to switch strategies by inhibiting the visual representation had fully developed. Children with good visual memory but poor auditory verbal memory would not only be expected to find acquisition of an effective phonological decoding strategy in reading rather difficult, but also be inclined to rely for a longer period on visual strategies. This approach is liable to run into trouble as the child’s education progresses and the number of new words with which the child is confronted steadily increases.