Flexible parafoveal encoding of character order supports word predictability effects in Chinese reading: Evidence from eye movements

Several eye-movement studies have revealed flexibility in the parafoveal processing of character-order information in Chinese reading. In particular, studies show that processing a two-character word in a sentence benefits more from parafoveal preview of a nonword created by transposing rather than replacing its two characters. One issue that has not been investigated is whether the contextual predictability of the target word influences this processing of character order information. However, such a finding would provide novel evidence for an early influence of context on lexical processing in Chinese reading. Accordingly, we investigated this issue in an eye-movement experiment using the boundary paradigm and sentences containing two-character target words with high or low contextual predictability. Prior to the reader’s gaze crossing an invisible boundary, each target word was shown normally (i.e. a valid preview) or with its two characters either transposed or replaced by unrelated characters to create invalid nonword previews. These invalid previews reverted to the target word once the reader’s gaze crossed the invisible boundary. The results showed larger preview benefits (i.e. a decrease in fixation times) for target words following transposed-character than substituted-character previews, revealing a transposed-character effect similar to that in previous research. In addition, a word predictability effect (shorter fixation times for words with high than low predictability) was observed following both valid and transposed-character previews, but not substituted-character previews. The findings therefore reveal that context can influence an early stage of lexical processing in Chinese reading during which character order is processed flexibly.

     

Parafoveal processing of words and saccade computation during eye fixations in reading

Studied parafoveal word processing during eye fixations in reading to answer two questions: (a) Is the processing of parafoveally available words limited to the identification of beginning letters? (b) Does the parafoveal processing of words affect the following interword saccade? Reading afforded either no parafoveal preview, preview of beginning trigrams, preview of ending trigrams, or preview of the whole parafoveal word. Previews were controlled by replacing original letters either with X's or dissimilar letters. Preview benefits were larger for the whole word previews than for beginning or ending trigram previews. X-masks yielded preview benefits from intact beginning and ending trigrams but dissimilar letter masks yielded benefits from beginning trigrams only. Saccades were larger for whole word previews than for no previews. These results support Logogen-type models of word recognition and a model of saccade computation that posits a time-locked functional relation between the acquisition of parafoveal word information and the positioning of each fixation.     

Is emotional content obtained from parafoveal words during reading? An eye movement analysis

An eye-movement-contingent display change technique was employed to study whether adult readers extract semantic information from parafoveal words during reading. Three types of parafoveal preview conditions were contrasted: an emotional word, a neutral word, and an identical word condition. To have a maximally effective parafoveal manipulation, high-arousal emotional words (sex- and threat-related and curse words) were used as parafoveal previews. Readers' eye fixation patterns around the target word revealed no evidence for parafoveal semantic processing. Furthermore, the pupil size showed no signs for an emotional response triggered by an emotional word previewed parafoveally. These results are consistent with the view that, as a rule, only the fixated word is processed to a semantic level during reading.     

单字词和复合词预视加工的差异性研究：词边界信息无影响

本实验采用眼动轨迹记录法并结合边界范式（Rayner, 1975），操纵单字词和双字复合词的首字为一致预视或假字预视，考察单字词和复合词预视加工的差异性。另外，通过在中文句子中加入词边界信息——词间阴影，以考察词间阴影对单字词和复合词预视加工的影响。实验结果表明，复合词的预视效应大于单字词，并且词间阴影对单字词和复合词的预视加工均没有显著影响。因此，与印欧语系相比，中文阅读中更大更强的预视效应需从更深层次的语言和认知因素进行探讨。该结果更倾向于支持词切分和词汇识别模型。     

单字词和复合词预视加工的差异性研究：词边界信息无影响

本实验采用眼动轨迹记录法并结合边界范式（Rayner, 1975）,操纵单字词和双字复合词的首字为一致预视或假字预视,考察单字词和复合词预视加工的差异性。另外,通过在中文句子中加入词边界信息——词间阴影,以考察词间阴影对单字词和复合词预视加工的影响。实验结果表明,复合词的预视效应大于单字词,并且词间阴影对单字词和复合词的预视加工均没有显著影响。因此,与印欧语系相比,中文阅读中更大更强的预视效应需从更深层次的语言和认知因素进行探讨。该结果更倾向于支持词切分和词汇识别模型。     

Vowel processing during silent reading: evidence from eye movements

Two eye movement experiments examined whether skilled readers include vowels in the early phonological representations used in word recognition during silent reading. Target words were presented in sentences preceded by parafoveal previews in which the vowel phoneme was concordant or discordant with the vowel phoneme in the target word. In Experiment 1, the orthographic vowel differed from the target in both the concordant and discordant preview conditions. In Experiment 2, the vowel letters in the preview were identical to those in the target word. The phonological vowel was ambiguous, however, and the final consonants of the previews biased the vowel phoneme either toward or away from the target's vowel phoneme. In both experiments, shorter reading times were observed for targets preceded by concordant previews than by discordant previews. Implications for models of word recognition are discussed.     

Encoding the target or the plausible preview word? The nature of the plausibility preview benefit in reading Chinese

Previous studies have shown that a plausible preview word can facilitate the processing of a target word as compared to an implausible preview word (a plausibility preview benefit effect) when reading Chinese (Yang, Wang, Tong, & Rayner, 2012; Yang, 2013). Regarding the nature of this effect, it is possible that readers processed the meaning of the plausible preview word and did not actually encode the target word (given that the parafoveal preview word lies close to the fovea). The current experiment examined this possibility with three conditions wherein readers received a preview of a target word that was either (1) identical to the target word (identical preview), (2) a plausible continuation of the pre-target text, but the post-target text in the sentence was incompatible with it (initially plausible preview), or (3) not a plausible continuation of the pre-target text, nor compatible with the post-target text (implausible preview). Gaze durations on target words were longer in the initially plausible condition than the identical condition. Overall, the results showed a typical preview benefit, but also implied that readers did not encode the initially plausible preview. Also, a plausibility preview benefit was replicated: gaze durations were longer with implausible previews than the initially plausible ones. Furthermore, late eye movement measures did not reveal differences between the initially plausible and the implausible preview conditions, which argues against the possibility of misreading the plausible preview word as the target word. In sum, these results suggest that a plausible preview word provides benefit in processing the target word as compared to an implausible preview word, and this benefit is only present in early but not late eye movement measures.     

中文阅读的副中央凹-中央凹效应：词n的语义透明度对词n-1的影响

研究探讨中文阅读中的副中央凹-中央凹效应。副中央凹-中央凹效应是指副中央凹处词的特性对中央凹处词汇加工的影响。实验以27名大学生为被试,采用句子阅读材料,考察词n的语义透明度特性对词n-1（高频、低频）加工的影响。结果表明,词n的语义透明度的高低对词n-1（高频、低频）的加工没有影响,没有出现副中央凹-中央凹效应。实验结果支持E-Z读者模型的假设。     

Distinct subsystems for the parafoveal processing of spatial and linguistic information during eye fixations in reading

Two experiments examined readers' use of parafoveally obtained word length information for word recognition. Both experiments manipulated the length (number of constituent characters) of a parafoveally previewed target word so that it was either accurately or inaccurately specified. In Experiment 1, previews also either revealed or denied useful orthographic information. In Experiment 2, parafoveal targets were either high- or low-frequency words. Eye movement contingent display changes were used to show the intact target upon its fixation. Examination of target viewing duration showed completely additive effects of word length previews and of ortho-graphic previews in Experiment 1, viewing duration being shorter in the accurate-length and the orthographic preview conditions. Experiment 2 showed completely additive effects of word length and word frequency, target viewing being shorter in the accurate-length and the high-frequency conditions. Together these results indicate that functionally distinct subsystems control the use of parafoveally visible spatial and linguistic information in reading. Parafoveally visible spatial information appears to be used for two distinct extralinguistic computations: visual object selection and saccade specification.     

Lexical priming from partial-word previews

Two naming and two lexical decision experiments examined the use of partial-word preview in visual word recognition. Replicating results of an earlier reading study, the results of Experiments 1 and 2 revealed significant benefits from position-specific beginning- and ending-letter previews. Furthermore, benefits from beginning letters were greater for words than for pseudowords. Ending-letter previews showed no corresponding lexical superiority. Experiment 3 revealed that preview of position-specific letters from the beginning plus the ending part of target stimuli, which did not reveal a unique word-beginning letter sequence, facilitated the classification of words but not pseudowords. The results support a two-route model of lexical access in which some partial-word previews afford activation of specific lexical representations, and some partial-word previews afford activation of subword representations.     

Contextual constraint and N + 2 preview effects in reading

Extracting linguistic information from locations beyond the currently fixated word is a core component of skilled reading. Recent debate on this topic is focused on the question of whether useful linguistic information can be extracted from more than one (parafoveally visible) word to the right of a fixated word (N). The current study examined this issue through the use parafoveal previews with a short and high-frequency next (N?+?1) word, as this should increase the opportunity for the extraction of useful information from the subsequent (N?+?2) word. Pairs of N?+?2 words were selected so that contextual constraint was either high or low. Using saccade contingent display manipulations, preview of a N?+?2 target word during word N viewing consisted of either a visually dissimilar nonword or a word. The results revealed a substantial drop in fixation probability for word N?+?1 when the N?+?2 preview was masked with a nonword. Furthermore, the masking of word N?+?2 influenced its viewing duration even when word N?+?1 was fixated prior to word N?+?2 viewing. These results provide compelling evidence for the view that the linguistic processing can encompass more than one word at a time.     

Parafoveal processing during reading is reduced across a morphological boundary

A boundary change manipulation was implemented within a monomorphemic word (e.g., fountaom as a preview for fountain), where parallel processing should occur given adequate visual acuity, and within an unspaced compound (bathroan as a preview for bathroom), where some serial processing of the constituents is likely. Consistent with that hypothesis, there was no effect of the preview manipulation on fixation time on the 1st constituent of the compound, whereas there was on the corresponding letters of the monomorphemic word. There was also a larger preview disruption on gaze duration on the whole monomorphemic word than on the compound, suggesting more parallel processing within monomorphemic words.     

Previewing the neighborhood: the role of orthographic neighbors as parafoveal previews in reading

In 2 experiments, a boundary technique was used with parafoveal previews that were identical to a target (e.g., sleet), a word orthographic neighbor (sweet), or an orthographically matched nonword (speet). In Experiment 1, low-frequency words in orthographic pairs were targets, and high-frequency words were previews. In Experiment 2, the roles were reversed. In Experiment 1, neighbor words provided as much preview benefit as identical words and greater benefit than nonwords, whereas in Experiment 2, neighbor words provided no greater preview benefit than nonwords. These results indicate that the frequency of a preview influences the extraction of letter information without setting up appreciable competition between previews and targets. This is consistent with a model of word recognition in which early stages largely depend on excitation of letter information, and competition between lexical candidates becomes important only in later stages.     

Lexical integration across saccades in reading

Summary Eye movements were recorded during sentence reading to examine the integration of parafoveal text across fixations. Four viewing conditions were used, each affording full view of the directly fixated word: no preview of the spatially adjacent parafoveal word; preview of its beginning trigram; preview of its beginning four letters; or preview of all its constituent letters. The magnitude of parafoveal-preview benefits (the difference between the no-preview condition and the different parafoveal-preview conditions) was examined as a function of the size of the saccade to the parafoveal target and as a function of the subsequent fixation location at the previewed target. The results revealed no effects of saccade size on parafoveal-preview benefits, but large effects of fixation position during the initial target fixation. Furthermore, parafoveal previews were used during the initial target fixation and during subsequent intratarget refixations. The results support a lexical-text-integration hypothesis which posits that lexical information is integrated across interword fixations and intraword refixations.     

How preview space/time translates into preview cost/benefit for fixation durations during reading

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.     

Parafoveal processing in reading: Manipulating n+1 and n+2 previews simultaneously

The boundary paradigm (Rayner, 1975) with a novel preview manipulation was used to examine the extent of parafoveal processing of words to the right of fixation. Words n+1 and n+2 had either correct or incorrect previews prior to fixation (prior to crossing the boundary location). In addition, the manipulation utilized either a high or low frequency word in word n+1 location on the assumption that it would be more likely that n+2 preview effects could be obtained when word n+1 was high frequency. The primary findings were that there was no evidence for a preview benefit for word n+2 and no evidence for parafoveal-on-foveal effects when word n+1 is at least four letters long. We discuss implications for models of eye-movement control in reading.     

A theoretical analysis of the perceptual span based on SWIFT simulations of the n + 2 boundary paradigm

Eye-movement experiments suggest that the perceptual span during reading is larger than the fixated word, asymmetric around the fixation position, and shrinks in size contingent on the foveal processing load. We used the SWIFT model of eye-movement control during reading to test these hypotheses and their implications under the assumption of graded parallel processing of all words inside the perceptual span. Specifically, we simulated reading in the boundary paradigm and analysed the effects of denying the model to have valid preview of a parafoveal word n + 2 two words to the right of fixation. Optimizing the model parameters for the valid preview condition only, we obtained span parameters with remarkably realistic estimates conforming to the empirical findings on the size of the perceptual span. More importantly, the SWIFT model generated parafoveal processing up to word n + 2 without fitting the model to such preview effects. Our results suggest that asymmetry and dynamic modulation are plausible properties of the perceptual span in a parallel word-processing model such as SWIFT. Moreover, they seem to guide the flexible distribution of processing resources during reading between foveal and parafoveal words.     

Parafoveal processing of transposed-letter words and nonwords: evidence against parafoveal lexical activation

The current experiments explored the parafoveal processing of transposed-letter (TL) neighbors by using an eye-movement-contingent boundary change paradigm. In Experiment 1 readers received a parafoveal preview of a target word (e.g., calm) that was either (1) identical to the target word (calm), (2) a TL-neighbor (clam), or (3) a substituted-letter (SL) nonword (chem). In Experiment 2 a further set of parafoveal preview conditions was explored including (4) an SL-word condition (chum) and (5) a TL-nonword condition (caml). Across both experiments, readers' fixation durations on the target words were significantly longer when the previews were SL previews than when they were TL neighbors, suggesting that TL neighbors (when presented in the parafovea) facilitate processing rather than inhibit processing. Experiments 3 and 4 showed that this is in contrast to the inhibitory effects that are seen when TL neighbor previews appear in the fovea.     

副中央凹中字N+2的预视对汉语阅读眼跳目标选择影响的眼动研究

采用边界范式, 在副中央凹呈现一个双字词或两个单字词, 操纵字N+2的预视(目标预视和假字预视), 来考察副中央凹中词汇特征是否影响读者随后的眼跳长度及注视位置。结果发现, 读者能够获得字N+2的预视; 双字词与两个单字词条件下注视位置没有显著地差异; 当副中央凹中为双字词时, 字N+2为目标预视时随后的眼跳长度显著地长于假字预视条件, 随后的注视位置距离词首更远; 当副中央凹中为两个单字词时, 两种预视条件下随后的眼跳长度及注视位置没有显著的差异。本研究结果提示：在汉语阅读中, 读者能够对字N+2进行预视加工, 这种加工的影响只发生在当副中央凹中为双字词时。