High-Level Vision in Dyslexia: The Possibility of Inefficient Visual Expertise as a Contributing Factor to Reading Problems

Abstract

A growing body of research suggests that dyslexic readers have problems with face recognition and other high-level visual tasks thought to rely on the ventral visual stream. Face and word recognition can both be seen as tasks relying on considerable visual expertise, and visual experience is considered necessary for the efficient shaping of neural representations in the ventral stream. Thus we tested whether visual expertise was compromised in dyslexia. For this purpose, we utilized the other-race effect, the finding that people are worse at discriminating other-race faces compared to own-race faces, generally considered a consequence of greater experience with own- race faces compared to other-race faces. It therefore serves as a marker of visual expertise. In the experiment, 24 dyslexic readers and 24 matched typical readers were tested on two measures of the other-race effect using Caucasian and Asian face-race stimuli. All participants were Caucasian with minimal Asian other-race contact. Dyslexic readers demonstrated problems with face recognition for both Caucasian and Asian faces. However, the strength of the other-race effect did not differ differ between dyslexic and typical readers. Measures of verbal short-term memory and ADHD symptoms could not account for these face recognition problems. We conclude that dyslexic readers might have problems in their recognition of faces and that compromised visual expertise cannot demonstrably account for these problems.