Orthographic similarity effect on the reading of a shallow orthography language: a study on children with and without dyslexia.

The study examines the effects on the reading aloud of the numerosity of words differing from a given word by changing one letter and preserving the positions of the other letters (N-size; Coltheart et al., 1977). Twenty-two Italian children with dyslexia and 44 skilled children attending 4th grade participated in the experiment. Children with dyslexia were faster in reading low frequency words with high N-size compared to words having no neighbors; by contrast, in skilled readers there were no N-size effects, irrespective of word frequency. Data suggest that children with dyslexia benefit from reading words sharing several letters with other words when the whole-word representation is not available in their orthographic lexicon, thereby partially overcoming their reading difficulty