Parafoveal preview benefit is modulated by the precision of skilled readers' lexical representations

In skilled reading, the processing of an upcoming word often begins in the parafovea, that is, before the word is fixated. This study investigated whether the extraction and use of multiple sources of information about an upcoming word depends on reading skill. The eye movements of 107 skilled adult readers, assessed on measures of reading and spelling ability, were recorded. The gaze-contingent boundary paradigm was used to manipulate the preview of a target word's identity and length in sentences with low- or high-frequency pretarget words. Across all first-pass reading measures, superior reading ability was associated with a larger preview benefit, but only among readers with high spelling ability, suggesting that the orthographic precision of a reader's stored lexical representations influences the extraction of parafoveal information. There was also evidence that the highly skilled reader/spellers' parafoveal processing advantage derived partly from their efficient foveal processing. Finally, in first fixations on the target, increased preview benefit for highly skilled reader/spellers was restricted to accurate length previews, suggesting that readers with precise lexical representations use upcoming word length in combination with parafoveal orthographic information to narrow down potential lexical candidates. The implications of these results for computational models of eye movements are discussed.