Phonological Processing and Right minus Left Hand Skill

Two experiments tested the hypothesis that children at the left of the distribution of right minus left (R-L) hand skill are at risk for poor phonological processing. In the first experiment, individual assessments of spoken rhyme awareness were made in 5- to 8-year-olds. In the second experiment, a group test of word order memory for spoken confusable and nonconfusable items was given to 9- to 11-year-olds. Evidence of poorer phonological processing in those at the left of the R-L distribution was found in both experiments. Rhyme judgements and word order memory were both associated with reading ability, but reading did not interact with effects for hand skill. A group test of homophone comprehension was given to the same children tested for word order memory. Homophone errors did not differ between hand skill groups, showing a dissociation between the two tasks for R-L hand difference. The findings suggest that some risks for phonological processing could be due to normal genetic variation associated with the hypothesized rs + gene (Annett, 1972, 1978).