The representation and processing of familiar faces in dyslexia: differences in age of acquisition effects.

Two under-explored areas of developmental dyslexia research, face naming and age of acquisition (AoA), were investigated. Eighteen dyslexic and 18 non-dyslexic university students named the faces of 50 well-known celebrities, matched for facial distinctiveness and familiarity. Twenty-five of the famous people were learned early in life, while the remaining 25 were first encountered more recently. There was no overall difference between the dyslexics and the non-dyslexics in the speed or the accuracy with which they named faces, suggesting that face naming is unimpaired in dyslexic adults. In keeping with previous findings, the results indicated a speed and accuracy advantage for early-acquired over late-acquired faces. In addition, a significant participant group x AoA interaction demonstrated that the non-dyslexic group was significantly faster to name early- than late-acquired faces, while the dyslexic group showed a much smaller and non-significant effect of AoA. The results suggest that there are differences in representation in dyslexia and that these may be linked to problems with attentional/executive function and automaticity. It is proposed that a more fine-grained approach to investigating dyslexia in adulthood should be adopted, in order to uncover cognitive as well as behavioural differences between dyslexics and non-dyslexics.