Two experiments used the gaze-contingent moving-window paradigm to investigate whether reading comprehension and spelling ability modulate the perceptual span of skilled adult readers during sentence reading. Highly proficient reading and spelling were both associated with increased use information to the right of fixation, but did not systematically modulate the extraction of information to the left of fixation. Individuals who were high in both reading and spelling ability showed the greatest benefit from window sizes larger than 11 characters, primarily because of increases in forward saccade length. They were also significantly more disrupted by being denied close parafoveal information than those poor in reading and/or spelling. These results suggest that, in addition to supporting rapid lexical retrieval of fixated words, the high quality lexical representations indexed by the combination of high reading and spelling ability support efficient processing of parafoveal information and effective saccadic targeting.

There is increasing evidence that skilled readers of English benefit from processing a parafoveal preview of a semantically related word. However, in previous investigations of semantic preview benefit using the gaze-contingent boundary paradigm the semantic relatedness between the preview and target has been confounded with the plausibility of the preview word in the sentence. In the present study, preview relatedness and plausibility were independently manipulated in neutral sentences read by a large sample of skilled adult readers. Participants were assessed on measures of reading and spelling ability to identify possible sources of individual differences in preview effects. The results showed that readers benefited from a preview of a plausible word, regardless of the semantic relatedness of the preview and the target. However, there was limited evidence of a semantic relatedness benefit when the plausibility of the preview was controlled. The plausibility preview benefit was strongest for low proficiency readers, suggesting that poorer readers were more likely to program a forward saccade based on information extracted from the preview. High proficiency readers showed equivalent disruption from all nonidentical previews suggesting that they were more likely to suffer interference from the orthographic mismatch between preview and target. (PsycINFO Database Record

Theories of eye movement control in reading assume that early oculomotor decisions are determined by a word's frequency and cloze probability. This assumption is challenged by evidence that readers are sensitive to the contextual plausibility of an upcoming word: Firstpass fixation probability and duration are reduced when the parafoveal preview is a plausible, but unpredictable, word relative to an implausible word. The present study sought to establish whether the source of this effect is sensitivity to violations of syntactic acceptability. In two experiments, the gaze-contingent boundary paradigm was used to compare contextually plausible previews to semantically acceptable and anomalous previews that either matched or violated syntactic rules. Results showed that readers benefited from the convergence of semantic and syntactic acceptability early enough in the timecourse of reading to affect skipping. In addition, both semantic and syntactic plausibility yielded preview effects on target fixation duration measures, providing direct evidence of parafoveal syntactic processing in reading. These results highlight the limitations of relying solely on cloze probability to index contextual influences on early lexical processing. The implications of the data for models of eye movement control and language comprehension are discussed.

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.

The boundary paradigm was used to investigate individual differences in the extraction of lexical information from the parafovea in sentence reading. The preview of a target word was manipulated so that it was identical (e.g., sped), a higher frequency orthographic neighbor (seed), a nonword neighbor (sted), or an all-letter-different nonword (glat). Ninety-four skilled adult readers were assessed on measures of reading and spelling ability. The results showed that null effects of preview lexical status in the average data obscured systematic differences on the basis of proficiency and target neighborhood density. For targets from dense neighborhoods, inhibition from a higher frequency neighbor preview occurred among highly proficient readers, and particularly those with superior spelling ability, in early fixation measures. Poorer readers showed inhibition only in second-pass reading of the target. These data suggest that readers with precise lexical representations are more likely to extract lexical information from a word before it is fixated. The implications for computational models of eye movements in reading are discussed.