Parafoveal preview differentially modulates word frequency and contextual predictability effects during reading

Despite over five decades of research into eye movements in reading, questionsremain about the relationship between lower-level lexical and higher-level semantic factors.We explored the simultaneous effects of word frequency (lower, higher), contextualpredictability (lower, higher), and parafoveal preview (valid, invalid) on the processing oftarget words embedded in short passages of text. Using a repeated-measures design, 80participants read 240 two-line passages, each containing a 4- or 5-letter target word. Corpus-based word frequencies and Cloze predictabilities were utilized as continuous variables inBayesian mixed-effect analyses of fixation time measures. Key findings included robust maineffects of frequency, predictability, and preview validity, as well as two-way interactionsbetween Preview × Frequency and Preview × Predictability, particularly in gaze duration.Frequency effects were greater under invalid preview conditions, suggesting that higherfrequency words facilitate corrective processing when preview is misleading. Predictabilityeffects were enhanced under valid preview, indicating that contextual facilitation depends oncoherent parafoveal input. No interaction was observed between frequency andpredictability, nor a three-way interaction, supporting the view that lexical access andcontextual integration operate via distinct mechanisms. These findings highlight the criticalrole of parafoveal information in shaping the expression of lexical and contextual influencesduring reading.