The present article presents a review of studies which investigated the relationship between phonological processing skills and the ability to read words in two developmental disorders: Down syndrome (DS) and Williams syndrome (WS). Results suggest that, like children without developmental disorders, individuals with DS and individuals with WS learn to read by processing and remembering letter-sound relations in words. It is nonetheless possible that non-phonological processes play a more important role in reading skills among individuals with DS and WS than among typically developed children. As discussed in the text, there is evidence that variations in non-verbal abilities are more strongly correlated with reading ability in DS and WS than among children with typical reading development.
Word reading; phonological processing; Down syndrome; Williams syndrome