When is a Visual Perceptual Deficit More Holistic but Less Right-lateralized? The Case of High-school Students with Dyslexia in Chinese

Abstract

Expert face recognition has been marked by holistic processing and left-side bias/right hemisphere involvement. Hence recognition for Chinese characters, sharing many visual perceptual properties with face perception, was thought to induce stronger holistic processing and left-side bias effect. However, Hsiao & Cottrell (2009) showed that expertise in Chinese character recognition involved reduced holistic processing, while Tso, Au & Hsiao (2014) suggested this effect may be modulated by writing experiences; in contrast, left-side bias was found to be a consistent expertise marker regardless of writing experiences. Here we examine holistic processing and left-side bias effect of Chinese character recognition between adolescents with and without dyslexia. Students with dyslexia were found to recognize Chinese characters with a stronger holistic processing effect than the typical controls. However, compared with the controls, dyslexics showed a more reduced left-side bias in processing mirror-symmetric Chinese characters. The theoretical and educational implications of these results were discussed.