chapter  3
64 Pages

Visual Mechanisms in Reading

This chapter emphasizes the impact of three aspects of visual processing on reading----contrast coding, size coding, and the decrease in spatial resolution outward from the fovea. In the first three sections of this chapter, we consider the impact of character size and contrast on reading. In sections 3.4 and 3.5, we link these psychophysical findings to the human contrast sensitivity function (CSF) and the representation of patterns by spatial-frequency channels. In section 3.6, we discuss reading in peripheral vision. We are interested in peripheral vision for two reasons: because it reveals a limitation of the CSF model of reading, and because people with central-field loss must rely on peripheral vision to read.