Chapter 19 - The flexibility of letter coding: Nonadjacent letter transposition effects in the parafovea

Abstract

Experiments have shown that transposed-letter (TL) nonwords produce significant priming relative to orthographic controls. Many current models of visual word recognition assume that letter positions are encoded very early in visual word recognition, even before the encoding of letter identities. Masked priming experiments indicate that TL effects exist even when the letter manipulations are nonadjacent, as long as the transposed letters are both consonants. This chapter presents data from a new study in which nonadjacent TL effects and the differential effects of vowels and consonants are explored during sentence reading using an eye-contingent display change paradigm. Although nonadjacent TL effects have previously been found only to exist at the foveal level when consonants are manipulated, the current findings indicate that these effects hold for both consonants and vowels presented in the parafovea. Although consonants and vowels may play different roles in foveal visual word recognition, the evidence presented in the chapter indicates that these two letter groups pattern similarly at the parafoveal level. The extraction of letter identity from the parafovea is not strictly dependent upon specific letter position, but rather, letter identity is encoded prior to letter position. These findings challenge models of visual word recognition that assume a channel-specific letter coding scheme and support models that allow more flexibility in the coding of letter identities.