As Chinese is written without orthographical word boundaries (i.e., spaces), it is unclear whether saccade targets are selected on the basis of characters or words and whether saccades are aimed at the beginning or the centre of words. Here, we report an experiment where 30 Chinese readers read 150 sentences while their eye movements were monitored. They exhibited a strong tendency to fixate at the word centre in single-fixation cases and at the word beginning in multiple-fixation cases. Different from spaced alphabetic script, initial fixations falling at the end of words were no more likely to be followed by a refixation than initial fixations at word centre. Further, single fixations were shorter than first fixations in two-fixation cases, which is opposite to what is found in Roman script. We propose that Chinese readers dynamically select the beginning or centre of words as saccade targets depending on failure or success with segmentation of parafoveal word boundaries.

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Linear mixed models (LMMs) provide a still underused methodological perspective on combining experimental and individual-differences research. Here we illustrate this approach with two-rectangle cueing in visual attention (Egly et al., 1994). We replicated previous experimental cue-validity effects relating to a spatial shift of attention within an object (spatial effect), to attention switch between objects (object effect), and to the attraction of attention toward the display centroid (attraction effect), also taking into account the design-inherent imbalance of valid and other trials. We simultaneously estimated variance/covariance components of subject-related random effects for these spatial, object, and attraction effects in addition to their mean reaction times (RTs). The spatial effect showed a strong positive correlation with mean RT and a strong negative correlation with the attraction effect. The analysis of individual differences suggests that slow subjects engage attention more strongly at the cued location than fast subjects. We compare this joint LMM analysis of experimental effects and associated subject-related variances and correlations with two frequently used alternative statistical procedures.

Eye-movement control during reading depends on foveal and parafoveal information. If the parafoveal preview of the next word is suppressed, reading is less efficient. A linear mixed model (LMM) reanalysis of McDonald (2006) confirmed his observation that preview benefit may be limited to parafoveal words that have been selected as the saccade target. Going beyond the original analyses, in the same LMM, we examined how the preview effect (i.e., the difference in single-fixation duration, SFD, between random-letter and identical preview) depends on the gaze duration on the pretarget word and on the amplitude of the saccade moving the eye onto the target word. There were two key results: (a) The shorter the saccade amplitude (i.e., the larger preview space), the shorter a subsequent SFD with an identical preview; this association was not observed with a random-letter preview. (b) However, the longer the gaze duration on the pretarget word, the longer the subsequent SFD on the target, with the difference between random-letter string and identical previews increasing with preview time. A third pattern-increasing cost of a random-letter string in the parafovea associated with shorter saccade amplitudes-was observed for target gaze durations. Thus, LMMs revealed that preview effects, which are typically summarized under "preview benefit", are a complex mixture of preview cost and preview benefit and vary with preview space and preview time. The consequence for reading is that parafoveal preview may not only facilitate, but also interfere with lexical access.

The present study explored the perceptual span (i.e., the physical extent of an area from which useful visual information is extracted during a single fixation) during the reading of Chinese sentences in 2 experiments. In Experiment 1, we tested whether the rightward span can go beyond 3 characters when visually similar masks were used. Results showed that Chinese readers needed at least 4 characters to the right of fixation to maintain a normal reading behavior when visually similar masks were used and when characters were displayed in small fonts, indicating that the span is dynamically influenced by masking materials. In Experiments 2 and 3, we asked whether the perceptual span varies as a function of font size in spaced (German) and unspaced (Chinese) scripts. Results clearly suggest perceptual span depends on font size in Chinese, but we failed to find such evidence for German. We propose that the perceptual span in Chinese is flexible; it is strongly constrained by its language-specific properties such as high information density and lack of word spacing. Implications for saccade-target selection during the reading of Chinese sentences are discussed.

Semantic processing from parafoveal words is an elusive phenomenon in alphabetic languages, but it has been demonstrated only for a restricted set of noncompound Chinese characters. Using the gaze-contingent boundary paradigm, this experiment examined whether parafoveal lexical and sublexical semantic information was extracted from compound preview characters. Results generalized parafoveal semantic processing to this representative set of Chinese characters and extended the parafoveal processing to radical (sublexical) level semantic information extraction. Implications for notions of parafoveal information extraction during Chinese reading are discussed.

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We measured Chinese dyslexic and control children's eye movements during rapid automatized naming (RAN) with alphanumeric (digits) and symbolic (dice surfaces) stimuli. Both types of stimuli required identical oral responses, controlling for effects associated with speech production. Results showed that naming dice was much slower than naming digits for both groups, but group differences in eye-movement measures and in the eye-voice span (i.e. the distance between the currently fixated item and the voiced item) were generally larger in digit-RAN than in dice-RAN. In addition, dyslexics were less efficient in parafoveal processing in these RAN tasks. Since the two RAN tasks required the same phonological output and on the assumption that naming dice is less practiced than naming digits in general, the results suggest that the translation of alphanumeric visual symbols into phonological codes is less efficient in dyslexic children. The dissociation of the print-to-sound conversion and phonological representation suggests that the degree of automaticity in translation from visual symbols to phonological codes in addition to phonological processing per se is also critical to understanding dyslexia.