Naming speed in children with dyslexia.

A series of tests of naming speed in discrete reaction time format were undertaken by seven groups of children: three groups with dyslexia with mean ages 8, 13, and 17 years; three groups of normally achieving children matched for age and IQ with the dyslexic groups; and a group of 10-year-old children with mild learning difficulties (slow learners) matched for reading age with the youngest dyslexic group. The children with dyslexia were significantly slower than even their chronological age-matched controls, and equivalent to their reading age-matched controls, on naming colors, digits, and letters, and significantly slower than even their reading age-matched controls on naming pictures of common objects. Overall, performance of the 17-year-old children with dyslexia was closest to that of the 8-year-old controls. Performance of the slow learners was equivalent to that of the youngest children with dyslexia. The results show that children with dyslexia have persistent-and unexpectedly severe-problems in naming speed for all stimuli, regardless of whether or not the stimulus requires grapheme-phoneme decoding.