Abstract

Only humans possess the high-level cognitive function of reading. The visual system is the best platform to study learning and plasticity of the brain during learning to read. For example, the high-level visual areas of the illiterate brain do not selectively respond to words, and only after successful reading acquisition, the visual word form area emerges from the already established areas that selectively respond to various object categories. Furthermore, in the reading circuitry, the visual system is at the front end of reading process. However, compared to research on language and high-level cognitive areas, the role of the visual system in reading has attracted little attention. In this review paper, we summarize the reading-related function of the visual system and discuss how deficits in the visual system relate to developmental dyslexia, learning disability in reading based on dyslexia research. Finally, we discuss reading as multi-sensory processing, in which one should associate arbitrary visual symbols with speech sounds. Previous research has shown the important role of the visual system in reading development and suggested deficits in the visual system might cause dyslexia. Our research suggests that intervention programs for dyslexia as well as research on reading development should include the results from research on the visual system.