The effects of phonological transparency on reading derived words

The purpose of this study was to determine whether poor readers have more pronounced problems than average-reading peers reading derived words the base forms of which undergo a phonological shift when a suffix is added (i.e., shift relations as in "natural"), as compared to derived words whose forms are phonologically and orthographically transparent (i.e., stable relations, as in "cultural"). Two computer-based word recognition tasks (Naming and Lexical Decision) were administered to children with reading disability (RD), peers with average reading ability and adults. Across tasks, there was an effect for transparency (i.e., better performance on stable than shift words) for both child groups and the adults. For the children, a significant interaction was found between group and word type. Specifically, on the naming task, there was an advantage for the stable words, and this was most noteworthy for the children with RD. On the lexical decision task, trade-offs of speed and accuracy were evident for the child reader groups. Performances on the nonwords showed the poor readers to be comparable to the average readers in distinguishing legal and illegal nonwords; further analyses suggested that poor readers carried out deeper processing of derived words than their average reading peers. Additional study is needed to explore the relation of orthographic and phonological processing on poor readers' memory for and processing of derived words.