Saccade Target Selection in Chinese Reading: The Roles of Contextual Constraint and Preview Validity

How readers use multiple sources of information to determine where to move their eyes during reading is a central question in eye movement control. In Chinese reading, both preview and contextual information have been shown to modulate saccade target selection. However, it remains unclear how contextual constraint and parafoveal preview jointly influence saccade targeting. The present study examined the relationship between contextual constraint and parafoveal preview in saccade target selection during Chinese reading. Participants' eye movements were recorded while they read sentences containing three-character target words embedded in either high- or low-constraint contexts. Using the boundary paradigm, we manipulated the preview validity of the target words: the preview was either identical to the target word (valid preview) or consisted of three pseudo-characters (invalid preview). The results showed a significant interaction between contextual constraint and preview validity on initial landing positions within the target word region and on saccade lengths entering the target word. Specifically, contextual constraint affected saccade targeting under valid preview conditions, whereas this effect was eliminated under invalid preview conditions. These findings indicate that saccade target selection during Chinese reading reflects a dynamically interactive process that integrates both preview (bottom-up) and contextual (top-down) information. The results provide empirical evidence that refines cognitive models of eye movement control in Chinese reading.