Parafoveal preview effects from word N + 1 and word N + 2 during reading: A critical review and Bayesian meta-analysis

Neural mechanism underlying preview effects and masked priming effects in visual word processing

Two classic experimental paradigms - masked repetition priming and the boundary paradigm - have played a pivotal role in understanding the process of visual word recognition. Traditionally, these paradigms have been employed by different communities of researchers, with their own long-standing research traditions. Nevertheless, a review of the literature suggests that the brain-electric correlates of word processing established with both paradigms may show interesting similarities, in particular with regard to the location, timing, and direction of N1 and N250 effects. However, as of yet, no direct comparison has been undertaken between the two paradigms. In the current study, we used combined eye-tracking/EEG to perform such a within-subject comparison using the same materials (single Chinese characters) as stimuli. To facilitate direct comparisons, we used a simplified version of the boundary paradigm - the single word boundary paradigm. Our results show the typical early repetition effects of N1 and N250 for both paradigms. However, repetition effects in N250 (i.e., a reduced negativity following identical-word primes/previews as compared to different-word primes/previews) were larger with the single word boundary paradigm than with masked priming. For N1 effects, repetition effects were similar across the two paradigms, showing a larger N1 after repetitions as compared to alternations. Therefore, the results indicate that at the neural level, a briefly presented and masked foveal prime produces qualitatively similar facilitatory effects on visual word recognition as a parafoveal preview before a single saccade, although such effects appear to be stronger in the latter case.

Visuospatial, oculomotor, and executive reading skills evolve in elementary school, and errors are significant: a topological RAN study

We investigate the development of visuospatial and oculomotor reading skills in a cohort of elementary school children. Employing a longitudinal methodology, the study applies the Topological serial digit Rapid Automated Naming (Top-RAN) battery, which evaluates visuospatial reading skills leveraging metrics addressing crowding, distractors, and voluntary attention orientation. The participant pool comprises 142 students (66 males, 76 females), including 46 non-native speakers (21 males, 25 females), representing a diverse range of ethnic backgrounds. The Top-RAN dataset encompasses performance, error, and self-correction metrics for each subtest and student, underscoring the significance of these factors in the process of reading acquisition. Analytical methods include dimensionality reduction, clustering, and classification algorithms, consolidated into a Python package to facilitate reproducible results. Our results indicate that visuospatial reading abilities vary according to the task and demonstrate a marked evolution over time, as seen in the progressive decrease in execution times, errors, and self-corrections. This pattern supports the hypothesis that the growth of oculomotor, attentional, and executive skills is primarily fostered by educational experiences and maturation. This investigation provides valuable insights into the dynamic nature of these skills during pivotal educational stages.

Parafoveal Processing of Orthography, Phonology, and Semantics during Chinese Reading: Effects of Foveal Load

The foveal load hypothesis assumes that the ease (or difficulty) of processing the currently fixated word in a sentence can influence processing of the upcoming word(s), such that parafoveal preview is reduced when foveal load is high. Recent investigations using pseudo-character previews reported an absence of foveal load effects in Chinese reading. Substantial Chinese studies to date provide some evidence to show that parafoveal words may be processed orthographically, phonologically, or semantically. However, it has not yet been established whether parafoveal processing is equivalent in terms of the type of parafoveal information extracted (orthographic, phonological, semantic) under different foveal load conditions. Accordingly, the present study investigated this issue with two experiments. Participants' eye movements were recorded as they read sentences in which foveal load was manipulated by placing a low- or high-frequency word N preceding a critical word. The preview validity of the upcoming word N + 1 was manipulated in Experiment 1, and word N + 2 in Experiment 2. The parafoveal preview was either identical to word N + 1(or word N + 2); orthographically related; phonologically related; semantically related; or an unrelated pseudo-character. The results showed robust main effects of frequency and preview type on both N + 1 and N + 2. Crucially, however, interactions between foveal load and preview type were absent, indicating that foveal load does not modulate the types of parafoveal information processed during Chinese reading.

Saccade execution increases the preview effect with faces: An EEG and eye-tracking coregistration study

Under naturalistic viewing conditions, humans conduct about three to four saccadic eye movements per second. These dynamics imply that in real life, humans rarely see something completely new; there is usually a preview of the upcoming foveal input from extrafoveal regions of the visual field. In line with results from the field of reading research, we have shown with EEG and eye-tracking coregistration that an extrafoveal preview also affects postsaccadic visual object processing and facilitates discrimination. Here, we ask whether this preview effect in the fixation-locked N170, and in manual responses to the postsaccadic target face (tilt discrimination), requires saccade execution. Participants performed a gaze-contingent experiment in which extrafoveal face images could change their orientation during a saccade directed to them. In a control block, participants maintained stable gaze throughout the experiment and the extrafoveal face reappeared foveally after a simulated saccade latency. Compared with this no-saccade condition, the neural and the behavioral preview effects were much larger in the saccade condition. We also found shorter first fixation durations after an invalid preview, which is in contrast to reading studies. We interpret the increased preview effect under saccade execution as the result of the additional sensorimotor processes that come with gaze behavior compared with visual perception under stable fixation. In addition, our findings call into question whether EEG studies with fixed gaze capture key properties and dynamics of active, natural vision.

Parafoveal syntactic processing from word N + 2 during reading: the case of gender-specific German articles

Previous research has suggested that some syntactic information such as word class can be processed parafoveally during reading. However, it is still unclear to what extent early syntactic cueing within noun phrases can facilitate word processing during dynamic reading. Two experiments (total N = 72) were designed to address this question using a gaze-contingent boundary change paradigm to manipulate the syntactic fit within a nominal phrase. Either the article (Experiment 1) or the noun (Experiment 2) was manipulated in the parafovea, resulting in a syntactic mismatch, depending on the condition. Results indicated a substantial elevation of viewing times on both parts of the noun phrase when conflicting syntactic information had been present in the parafovea. In Experiment 1, the article was also fixated more often in the syntactic mismatch condition. These results provide direct evidence of parafoveal syntactic processing. Based on the early time-course of this effect, it can be concluded that grammatical gender is used to generate constraints for the processing of upcoming nouns. To our knowledge, these results also provide the first evidence that syntactic information can be extracted from a parafoveal word N + 2.

The role of visual crowding in eye movements during reading: Effects of text spacing

Visual crowding, generally defined as the deleterious influence of clutter on visual discrimination, is a form of inhibitory interaction between nearby objects. While the role of crowding in reading has been established in psychophysics research using rapid serial visual presentation (RSVP) paradigms, how crowding affects additional processes involved in natural reading, including parafoveal processing and saccade targeting, remains unclear. The current study investigated crowding effects on reading via two eye-tracking experiments. Experiment 1 was a sentence-reading experiment incorporating an eye-contingent boundary change in which reader's parafoveal processing was quantified through comparing reading times after valid or invalid information was presented in the parafovea. Letter spacing was jointly manipulated to compare how crowding affects parafoveal processing. Experiment 2 was a passage-reading experiment with a line spacing manipulation. In addition to replicating previously observed letter spacing effects on global reading parameters (i.e., more but shorter fixations with wider spacing), Experiment 1 found an interaction between preview validity and letter spacing indicating that the efficiency of parafoveal processing was constrained by crowding and visual acuity. Experiment 2 found reliable but subtle influences of line spacing. Participants had shorter fixation durations, higher skipping probabilities, and less accurate return sweeps when line spacing was increased. In addition to extending the literature on the role of crowding to reading in ecologically valid scenarios, the current results inform future research on characterizing the influence of crowding in natural reading and comparing effects of crowding across reader populations.

Mask-related costs in measuring preview benefit: Evidence from a distributional analysis based on target word reading times

Skilled reading involves processing the upcoming word in parafoveal vision before it is fixated, leading to shorter fixations on that word. This phenomenon, parafoveal preview benefit, is a key component of theoretical models of reading; it is measured using the invisible boundary paradigm, in which reading times on a target word are compared for instances when preview is accurate and when the target word is masked while in the parafovea. However, parafoveal masks have been shown to induce unintentional processing costs, thereby inflating measures of preview benefit. The degraded mask has been explored as a potential solution to this problem, leading to mixed results. While previous work has analyzed the preview effect by comparing mean reading times on the target word, the present study provides a more comprehensive analysis by examining the distribution of the preview effect across target word fixation times for unrelated and degraded masks. Participants read sentences containing target words whose preview was either identical, unrelated, or degraded, and their eye movements were recorded. Analyses revealed that although there were no mean differences between reading times for the unrelated and degraded conditions, the pattern of the effects varied as a function of target word fixation times. Unrelated masks resulted in positively sloped generally linear delta plots, while degraded masks resulted in relatively flat delta plots for fixations longer than 200 ms. These differences suggest that different cognitive mechanisms are involved in the processing of the two mask types. Implications for understanding and measuring preview benefit are discussed.

Constraints on integration of orthographic information across multiple stimuli: effects of contiguity, eccentricity, and attentional span

Five flanked lexical decision experiments investigated the integration of information across spatially distinct letter strings. Experiment 1 found no significant difference between quadrigram flankers (e.g., CKRO ROCK CKRO) and double bigram flankers (e.g., CK RO ROCK CK RO). Experiment 2 varied the eccentricity of single bigram flankers and found that closer flankers generated greater effects. A combined analysis of these experiments revealed that the double bigram condition (Experiment 1) was less effective than the close single bigram condition (Experiment 2). Experiment 3 tested one explanation for this pattern - that the outer bigrams in the double bigram condition interfered with processing the inner bigrams, and that spatial integration only operates across adjacent stimuli. In Experiment 3, outer bigrams were now a repeat of the inner bigram (e.g., RO RO ROCK CK CK), and this repeated bigram condition was still found to be significantly less effective than single bigrams. Experiments 4 and 5 tested an alternative explanation whereby the addition of spatially distinct flanking stimuli increases the spread of spatial attention, hence reducing the impact of proximal flankers. In line with this explanation, we found no significant difference between repeated bigram flankers and a condition where only the inner bigram was related to the target (e.g., CA RO ROCK CK SH). We conclude that spatial integration processes only operate across the central target and proximal flankers, and that these effects are diluted by the increased spread of spatial attention caused by additional spatially distinct flankers.

The graded predictive pre-activation in Chinese sentence reading: evidence from eye movements

Previous research has revealed that graded pre-activation rather than specific lexical prediction is more likely to be the mechanism for the word predictability effect in English. However, whether graded pre-activation underlies the predictability effect in Chinese reading is unknown. Accordingly, the present study tested the generality of the graded pre-activation account in Chinese reading. We manipulated the contextual constraint of sentences and the predictability of target words as independent variables. Readers' eye movement behaviors were recorded via an eye tracker. We examined whether processing an unpredictable word in a solid constraining context incurs a prediction error cost when this unpredictable word has a predictable alternative. The results showed no cues of prediction error cost on the early eye movement measures, supported by the Bayes Factor analyses. The current research indicates that graded predictive pre-activation underlies the predictability effect in Chinese reading.

Examining the extraction of parafoveal semantic information in Tibetan

This study conducted two experiments to investigate the extraction of semantic preview information from the parafovea in Tibetan reading. In Experiment 1, a single-factor (preview type: identical vs. semantically related vs. unrelated) within-subject experimental design was used to investigate whether there is a parafoveal semantic preview effect (SPE) in Tibetan reading. Experiment 2 used a 2 (contextual constraint: high vs. low) × 3 (preview type: identical vs. semantically related vs. unrelated) within-subject experimental design to investigate the influence of contextual constraint on the parafoveal semantic preview effect in Tibetan reading. Supporting the E-Z reader model, the experimental results showed that in Tibetan reading, readers could not obtain semantic preview information from the parafovea, and contextual constraint did not influence this process. However, comparing high- and low-constrained contexts, the latter might be more conducive to extracting semantic preview information from the parafovea.

Word complexity modulates the divided-word effect during Chinese reading

The present study examined the influence of word complexity on the divided-word effect. By manipulating presentation conditions (line-final presentation vs. divided-word presentation vs. line-initial presentation) and visual complexity (high vs. low), we found a significant divided-word effect that the reading times such as gaze duration and total reading time were significantly longer in the divided-word presentation condition than in both the line-final and line-initial presentation conditions. On the measure of total reading time, the marginally significant interaction between the divided-word versus line-final presentation comparison and complexity showed that the divided-word effect was larger for low complexity words than that for high complexity words. These results suggest that dividing a word across two lines interferes with reading, and word complexity modulates this effect.

Preview frequency effects in reading: evidence from Chinese

Studies about sentence reading have shown that visual and lexical information beyond the currently fixated word can be integrated across fixations. The gaze-contingent boundary paradigm has been used widely to explore the extent to which parafoveal information can be processed before a word is fixated on. However, a critical review of the current literature suggests that unrelated mask previews are an unlikely baseline control with zero lexical activation, blurring the nature of experimental effects observed in the paradigm. The present study, therefore, aimed at shedding light on the effect of parafoveal mask properties through a manipulation of preview word frequency. Low-frequency preview words that are unrelated to target words elicited a larger interference than high-frequency preview words. We discuss implications of the preview frequency effect for computational models of eye-movement control in reading.

Cross-linguistic differences in parafoveal semantic and orthographic processing

In this study we investigated parafoveal processing by L1 and late L2 speakers of English (L1 German) while reading in English. We hypothesized that L2ers would make use of semantic and orthographic information parafoveally. Using the gaze contingent boundary paradigm, we manipulated six parafoveal masks in a sentence (Mark found th*e wood for the fire; * indicates the invisible boundary): identical word mask (wood), English orthographic mask (wook), English string mask (zwwl), German mask (holz), German orthographic mask (holn), and German string mask (kxfs). We found an orthographic benefit for L1ers and L2ers when the mask was orthographically related to the target word (wood vs. wook) in line with previous L1 research. English L2ers did not derive a benefit (rather an interference) when a non-cognate translation mask from their L1 was used (wood vs. holz), but did derive a benefit from a German orthographic mask (wood vs. holn). While unexpected, it may be that L2ers incur a switching cost when the complete German word is presented parafoveally, and derive a benefit by keeping both lexicons active when a partial German word is presented parafoveally (narrowing down lexical candidates). To the authors’ knowledge there is no mention of parafoveal processing in any model of L2 processing/reading, and the current study provides the first evidence for a parafoveal non-cognate orthographic benefit (but only with partial orthographic overlap) in sentence reading for L2ers. We discuss how these findings fit into the framework of bilingual word recognition theories.

The extrafoveal preview paradigm as a measure of predictive, active sampling in visual perception

A key feature of visual processing in humans is the use of saccadic eye movements to look around the environment. Saccades are typically used to bring relevant information, which is glimpsed with extrafoveal vision, into the high-resolution fovea for further processing. With the exception of some unusual circumstances, such as the first fixation when walking into a room, our saccades are mainly guided based on this extrafoveal preview. In contrast, the majority of experimental studies in vision science have investigated "passive" behavioral and neural responses to suddenly appearing and often temporally or spatially unpredictable stimuli. As reviewed here, a growing number of studies have investigated visual processing of objects under more natural viewing conditions in which observers move their eyes to a stationary stimulus, visible previously in extrafoveal vision, during each trial. These studies demonstrate that the extrafoveal preview has a profound influence on visual processing of objects, both for behavior and neural activity. Starting from the preview effect in reading research we follow subsequent developments in vision research more generally and finally argue that taking such evidence seriously leads to a reconceptualization of the nature of human visual perception that incorporates the strong influence of prediction and action on sensory processing. We review theoretical perspectives on visual perception under naturalistic viewing conditions, including theories of active vision, active sensing, and sampling. Although the extrafoveal preview paradigm has already provided useful information about the timing of, and potential mechanisms for, the close interaction of the oculomotor and visual systems while reading and in natural scenes, the findings thus far also raise many new questions for future research.

Saccade Landing Point Prediction Based on Fine-Grained Learning Method

The landing point of a saccade defines the new fixation region, the new region of interest. We asked whether it was possible to predict the saccade landing point early in this very fast eye movement. This work proposes a new algorithm based on LSTM networks and a fine-grained loss function for saccade landing point prediction in real-world scenarios. Predicting the landing point is a critical milestone toward reducing the problems caused by display-update latency in gaze-contingent systems that make real-time changes in the display based on eye tracking. Saccadic eye movements are some of the fastest human neuro-motor activities with angular velocities of up to 1,000°/s. We present a comprehensive analysis of the performance of our method using a database with almost 220,000 saccades from 75 participants captured during natural viewing of videos. We include a comparison with state-of-the-art saccade landing point prediction algorithms. The results obtained using our proposed method outperformed existing approaches with improvements of up to 50% error reduction. Finally, we analyzed some factors that affected prediction errors including duration, length, age, and user intrinsic characteristics.

Regression-based analysis of combined EEG and eye-tracking data: Theory and applications

Fixation-related potentials (FRPs), neural responses aligned to the end of saccades, are a promising tool for studying the dynamics of attention and cognition under natural viewing conditions. In the past, four methodological problems have complicated the analysis of such combined eye-tracking/electroencephalogram experiments: (1) the synchronization of data streams, (2) the removal of ocular artifacts, (3) the condition-specific temporal overlap between the brain responses evoked by consecutive fixations, and (4) the fact that numerous low-level stimulus and saccade properties also influence the postsaccadic neural responses. Although effective solutions exist for the first two problems, the latter two are only beginning to be addressed. In the current paper, we present and review a unified regression-based framework for FRP analysis that allows us to deconvolve overlapping potentials while also controlling for both linear and nonlinear confounds on the FRP waveform. An open software implementation is provided for all procedures. We then demonstrate the advantages of this proposed (non)linear deconvolution modeling approach for data from three commonly studied paradigms: face perception, scene viewing, and reading. First, for a traditional event-related potential (ERP) face recognition experiment, we show how this technique can separate stimulus ERPs from overlapping muscle and brain potentials produced by small (micro)saccades on the face. Second, in natural scene viewing, we model and isolate multiple nonlinear effects of saccade parameters on the FRP. Finally, for a natural sentence reading experiment using the boundary paradigm, we show how it is possible to study the neural correlates of parafoveal preview after removing spurious overlap effects caused by the associated difference in average fixation time. Our results suggest a principal way of measuring reliable eye movement-related brain activity during natural vision.

The Effect of Word Predictability on Phonological Activation in Cantonese Reading: A Study of Eye-Fixations and Pupillary Response

This study aimed to investigate the effects of contextual predictability on orthographic and phonological activation during Chinese sentence reading by Cantonese-speaking readers using the error disruption paradigm. Participants' eye fixations and pupil sizes were recorded while they silently read Chinese sentences containing homophonic, orthographic, and unrelated errors. Sentences had varying amounts of contextual information leading up to target words such that some targets were more predictable than others. Results of the fixation time analysis indicated that orthographic effects were significant in first fixation and gaze duration, while phonological effects emerged later in total reading time. However, interactions between predictability and the homophonic condition were found in gaze duration. These results suggest that, while Cantonese readers activate word meanings primarily through orthography in early processing, early phonological activation can occur when facilitated by semantics in high-constraint sentence contexts. Analysis of pupillary response measurements revealed that participants' pupil sizes became larger when they read words containing orthographic errors, suggesting that orthographic error recovery processes significantly increase cognitive load.

Parafoveal degradation during reading reduces preview costs only when it is not perceptually distinct

There is a growing understanding that the parafoveal preview effect during reading may represent a combination of preview benefits and preview costs due to interference from parafoveal masks. It has been suggested that visually degrading the parafoveal masks may reduce their costs, but adult readers were later shown to be highly sensitive to degraded display changes. Four experiments examined how preview benefits and preview costs are influenced by the perception of distinct parafoveal degradation at the target word location. Participants read sentences with four preview types (identity, orthographic, phonological, and letter-mask preview) and two levels of visual degradation (0% vs. 20%). The distinctiveness of the target word degradation was either eliminated by degrading all words in the sentence (Experiments 1a–2a) or remained present, as in previous research (Experiments 1b–2b). Degrading the letter masks resulted in a reduction in preview costs, but only when all words in the sentence were degraded. When degradation at the target word location was perceptually distinct, it induced costs of its own, even for orthographically and phonologically related previews. These results confirm previous reports that traditional parafoveal masks introduce preview costs that overestimate the size of the true benefit. However, they also show that parafoveal degradation has the unintended consequence of introducing additional costs when participants are aware of distinct degradation on the target word. Parafoveal degradation appears to be easily perceived and may temporarily orient attention away from the reading task, thus delaying word processing.

The impact of uninformative parafoveal masks on L1 and late L2 speakers

Much reading research has found that informative parafoveal masks lead to a reading benefit for native speakers (see 1). However, little reading research has tested the impact of uninformative parafoveal masks during reading. Additionally, parafoveal processing research is primarily restricted to native speakers. In the current study we manipulated the type of uninformative preview using a gaze contingent boundary paradigm with a group of L1 English speakers and a group of late L2 English speakers (L1 German). We were interested in how different types of uninformative masks impact on parafoveal processing, whether L1 and L2 speakers are similarly impacted, and whether they are sensitive to parafoveally viewed language-specific sub-lexical orthographic information. We manipulated six types of uninformative masks to test these objectives: an Identical, English pseudo-word, German pseudo-word, illegal string of letters, series of X's, and a blank mask. We found that X masks affect reading the most with slight graded differences across the other masks, L1 and L2 speakers are impacted similarly, and neither group is sensitive to sub-lexical orthographic information. Overall these data show that not all previews are equal, and research should be aware of the way uninformative masks affect reading behavior. Additionally, we hope that future research starts to approach models of eye-movement behavior during reading from not only a monolingual but also from a multilingual perspective.

Readers detect an low-level phonological violation between two parafoveal words

In two eye-tracking studies we investigated whether readers can detect a violation of the phonological-grammatical convention for the indefinite article an to be followed by a word beginning with a vowel when these two words appear in the parafovea. Across two experiments participants read sentences in which the word an was followed by a parafoveal preview that was either correct (e.g. Icelandic), incorrect and represented a phonological violation (e.g. Mongolian), or incorrect without representing a phonological violation (e.g. Ethiopian), with this parafoveal preview changing to the target word as participants made a saccade into the space preceding an. Our data suggests that participants detected the phonological violation while the target word was still two words to the right of fixation, with participants making more regressions from the previewed word and having longer go-past times on this word when they received a violation preview as opposed to a non-violation preview. We argue that participants were attempting to perform aspects of sentence integration on the basis of low-level orthographic information from the previewed word.

Sign phonological parameters modulate parafoveal preview effects in deaf readers

Research has found that deaf readers unconsciously activate sign translations of written words while reading. However, the ways in which different sign phonological parameters associated with these sign translations tie into reading processes have received little attention in the literature. In this study on Chinese reading, we used a parafoveal preview paradigm to investigate how four different types of sign phonologically related preview affect reading processes in adult deaf signers of Hong Kong Sign Language (HKSL). The four types of sign phonologically related preview-target pair were: (1) pairs with HKSL translations that overlapped in three parameters-handshape, location, and movement; (2) pairs that overlapped in only handshape and location; (3) pairs that only overlapped in handshape and movement; and (4) pairs that only overlapped in location and movement. Results showed that the handshape parameter was of particular importance as only sign translation pairs that had handshape among their overlapping sign phonological parameters led to early sign activation. Furthermore, we found that, compared to control previews, deaf readers took longer to read targets when the sign translation previews overlapped with targets in either handshape and movement or handshape, movement, and location. In contrast, fixation times on targets were shorter when previews and targets overlapped location and any single additional parameter-either handshape or movement. These results indicate that the phonological parameters of handshape, location, and movement are activated via orthography during Chinese reading and can have different effects on parafoveal processing in deaf signers of HKSL.

Readers can identify the meanings of words without looking at them: Evidence from regressive eye movements

Previewing words prior to fixating them leads to faster reading, but does it lead to word identification (i.e., semantic encoding)? We tested this with a gaze-contingent display change study and a subsequent plausibility manipulation. Both the preview and the target words were plausible when encountered, and we manipulated the end of the sentence so that the different preview was rendered implausible (in critical sentences) or remained plausible (in neutral sentences). Regressive saccades from the end of the sentence increased when the preview was rendered implausible compared to when it was plausible, especially when the preview was high frequency. These data add to a growing body of research suggesting that linguistic information can be obtained during preview, to the point where word meaning is accessed. In addition, these findings suggest that the meaning of the fixated target does not always override the semantic information obtained during preview.

The effect of contextual plausibility on word skipping during reading

Recent eye-movement evidence suggests readers are more likely to skip a high-frequency word than a low-frequency word independently of the semantic or syntactic acceptability of the word in the sentence. This has been interpreted as strong support for a serial processing mechanism in which the decision to skip a word is based on the completion of a preliminary stage of lexical processing prior to any assessment of contextual fit. The present large-scale study was designed to reconcile these findings with the plausibility preview effect: higher skipping and reduced first-pass reading times for words that are previewed by contextually plausible, compared to implausible, sentence continuations that are unrelated to the target word. Participants' eye movements were recorded as they read sentences containing a short (3-4 letters) or long (6 letters) target word. The boundary paradigm was used to present parafoveal previews which were either higher or lower frequency than the target, and either plausible or implausible in the sentence context. The results revealed strong, independent effects of all three factors on target skipping and early measures of target fixation duration, while frequency and plausibility interacted on later measures of target fixation duration. Simulations using the E-Z Reader model of eye-movement control in reading demonstrated that plausibility effects on skipping are potentially consistent with the assumption that higher-level contextual information only affects post-lexical integration processes. However, no current model of eye movements in reading provides an explicit account of the information or processes that allow readers to rapidly detect an integration failure.

A co-registration investigation of inter-word spacing and parafoveal preview: Eye movements and fixation-related potentials

Participants' eye movements (EMs) and EEG signal were simultaneously recorded to examine foveal and parafoveal processing during sentence reading. All the words in the sentence were manipulated for inter-word spacing (intact spaces vs. spaces replaced by a random letter) and parafoveal preview (identical preview vs. random letter string preview). We observed disruption for unspaced text and invalid preview conditions in both EMs and fixation-related potentials (FRPs). Unspaced and invalid preview conditions received longer reading times than spaced and valid preview conditions. In addition, the FRP data showed that unspaced previews disrupted reading in earlier time windows of analysis, compared to string preview conditions. Moreover, the effect of parafoveal preview was greater for spaced relative to unspaced conditions, in both EMs and FRPs. These findings replicate well-established preview effects, provide novel insight into the neural correlates of reading with and without inter-word spacing and suggest that spatial selection precedes lexical processing.

Do Readers Integrate Phonological Codes Across Saccades? A Bayesian Meta-Analysis and a Survey of the Unpublished Literature

It is commonly accepted that phonological codes can be activated parafoveally during reading and later used to aid foveal word recognition- a finding known as the phonological preview benefit. However, a closer look at the literature shows that this effect may be less consistent than what is sometimes believed. To determine the extent to which phonology is processed parafoveally, a Bayesian meta-analysis of 27 experiments and a survey of the unpublished literature were conducted. While the results were generally consistent with the phonological preview benefit (>90% probability of a true effect in gaze durations), the size of the effect was small. Readers of alphabetical orthographies obtained a modest benefit of only 4 ms in gaze durations. Interestingly, Chinese readers showed a larger effect (6-14 ms in size). There was no difference in the magnitude of the phonological preview benefit between homophone and pseudo-homophone previews, thus suggesting that the modest processing advantage is indeed related to the activation of phonological codes from the parafoveal word. Simulations revealed that the results are relatively robust to missing studies, although the effects may be 19-22% smaller if all missing studies found a null effect. The results suggest that while phonology can be processed parafoveally, this happens only to a limited extent. Because phonological priming effects in single-word recognition are small (10-13 ms; Rastle & Brysbaert, 2006) and there is a loss of visual acuity in the parafovea, it is argued that large phonological preview benefit effects may be unlikely.

Word skipping in Chinese reading: The role of high-frequency preview and syntactic felicity

Two experiments are reported to investigate whether Chinese readers skip a high-frequency preview word without taking the syntax of the sentence context into account. In Experiment 1, we manipulated target word syntactic category, frequency, and preview using the boundary paradigm (Rayner, 1975). For high-frequency verb targets, there were identity and pseudocharacter previews alongside a low-frequency noun preview. For low-frequency verb targets, there were identity and pseudocharacter previews alongside a high-frequency noun preview. Results showed that for high-frequency targets, skipping rates were higher for identical previews compared with the syntactically infelicitous alternative low-frequency preview and pseudocharacter previews, however for low-frequency targets, skipping rates were higher for high-frequency previews (even when they were syntactically infelicitous) compared with the other 2 previews. Furthermore, readers were more likely to skip the target when they had a high-frequency, syntactically felicitous preview compared to a high-frequency, syntactically infelicitous preview. The pattern of felicity effects was statistically robust when readers launched saccades from near the target. In Experiment 2, we assessed whether display change awareness influenced the patterns of results in Experiment 1. Results showed that the overall patterns held in Experiment 2 regardless of some readers being more likely to be aware of the display change than others. These results suggest that decisions to skip a word in Chinese reading are primarily based on parafoveal word familiarity, though the syntactic felicity of a parafoveal word also exerts a robust influence for high-frequency previews.

Parafoveal previews and lexical frequency in natural reading: Evidence from eye movements and fixation-related potentials

Participants' eye movements and electroencephalogram (EEG) signal were recorded as they read sentences displayed according to the gaze-contingent boundary paradigm. Two target words in each sentence were manipulated for lexical frequency (high vs. low frequency) and parafoveal preview of each target word (identical vs. string of random letters vs. string of Xs). Eye movement data revealed visual parafoveal-on-foveal (PoF) effects, as well as foveal visual and orthographic preview effects and word frequency effects. Fixation-related potentials (FRPs) showed visual and orthographic PoF effects as well as foveal visual and orthographic preview effects. Our results replicated the early preview positivity effect (Dimigen, Kliegl, & Sommer, 2012) in the X-string preview condition, and revealed different neural correlates associated with a preview comprised of a string of random letters relative to a string of Xs. The former effects seem likely to reflect difficulty associated with the integration of parafoveal and foveal information, as well as feature overlap, while the latter reflect inhibition, and potentially disruption, to processing underlying reading. Interestingly, and consistent with Kretzschmar, Schlesewsky, and Staub (2015), no frequency effect was reflected in the FRP measures. The findings provide insight into the neural correlates of parafoveal processing and written word recognition in reading and demonstrate the value of utilizing ecologically valid paradigms to study well established phenomena that occur as text is read naturally. (PsycINFO Database Record (c) 2019 APA, all rights reserved).

Stable preview difficulty effects in reading with an improved variant of the boundary paradigm

Using gaze-contingent display changes in the boundary paradigm during sentence reading, it has recently been shown that parafoveal word-processing difficulties affect fixations on words to the right of the boundary. Current interpretations of this post-boundary preview difficulty effect range from delayed parafoveal-on-foveal effects in parallel word-processing models to forced fixations in serial word-processing models. However, these findings are based on an experimental design that, while allowing to isolate preview difficulty effects, might have established a bias with respect to asymmetries in parafoveal preview benefit for high-frequent and low-frequent target words. Here, we present a revision of this paradigm varying the preview's lexical frequency and keeping the target word constant. We found substantial effects of the preview difficulty in fixation durations after the boundary confirming that preview processing affects the oculomotor decisions not only via trans-saccadic integration of preview and target word information. An additional time-course analysis showed that the preview difficulty effect was significant across the full fixation duration distribution on the target word without any evidence on the pretarget word before the boundary. We discuss implications of the accumulating evidence of post-boundary preview difficulty effects for models of eye movement control during reading.

Influences on and consequences of parafoveal preview in reading

During reading, information is extracted from upcoming words to the right of the currently fixated word, which facilitates recognition of those words when they are later fixated. According to the foveal load hypothesis (Henderson & Ferreira, 1990), this parafoveal preview benefit depends on how difficult the currently fixated word is to recognize. Furthermore, there is evidence that the influence of lexical variables (frequency and predictability) on word processing changes when no preview of that word is available. The present study reports two moving-window experiments in which the upcoming word to the right of fixation was either included in or excluded from the window. Through this manipulation, accurate parafoveal information was either available or not for each word in the paragraph. Two critical interactions between preview condition and lexical variables were observed. First, the word frequency at word N was found to be the primary influence on the amount of preview benefit obtained at word N+1, consistent with the foveal load hypothesis. Second, denial of preview eliminated the word predictability effect. These findings have implications for models of eye movement control in reading.

Auditory Distraction During Reading: A Bayesian Meta-Analysis of a Continuing Controversy

Everyday reading occurs in different settings, such as on the train to work, in a busy cafeteria, or at home while listening to music. In these situations, readers are exposed to external auditory stimulation from nearby noise, speech, or music that may distract them from their task and reduce their comprehension. Although many studies have investigated auditory-distraction effects during reading, the results have proved to be inconsistent and sometimes even contradictory. In addition, the broader theoretical implications of the findings have not always been explicitly considered. We report a Bayesian meta-analysis of 65 studies on auditory-distraction effects during reading and use metaregression models to test predictions derived from existing theories. The results showed that background noise, speech, and music all have a small but reliably detrimental effect on reading performance. The degree of disruption in reading comprehension did not generally differ between adults and children. Intelligible speech and lyrical music resulted in the biggest distraction. Although this last result is consistent with theories of semantic distraction, there was also reliable distraction by noise. It is argued that new theoretical models are needed that can account for distraction by both background speech and noise.

Effects of aging, word frequency, and text stimulus quality on reading across the adult lifespan: Evidence from eye movements

Reductions in stimulus quality may disrupt the reading performance of older adults more when compared with young adults because of sensory declines that begin early in middle age. However, few studies have investigated adult age differences in the effects of stimulus quality on reading, and none have examined how this affects lexical processing and eye movement control. Accordingly, we report two experiments that examine the effects of reduced stimulus quality on the eye movements of young (18–24 years), middle-aged (41–51 years), and older (65+ years) adult readers. In Experiment 1, participants read sentences that contained a high- or low-frequency critical word and that were presented normally or with contrast reduced so that words appeared faint. Experiment 2 further investigated effects of reduced stimulus quality using a gaze-contingent technique to present upcoming text normally or with contrast reduced. Typical patterns of age-related reading difficulty (e.g., slower reading, more regressions) were observed in both experiments. In addition, eye movements were disrupted more for older than younger adults when all text (Experiment 1) or just upcoming text (Experiment 2) appeared faint. Moreover, there was an interaction between stimulus quality and word frequency (Experiment 1), such that readers fixated faint low-frequency words for disproportionately longer. Crucially, this effect was similar across all age groups. Thus, although older readers suffer more from reduced stimulus quality, this additional difficulty primarily affects their visual processing of text. These findings have important implications for understanding the role of stimulus quality on reading behavior across the lifespan.

Binocular advantages for parafoveal processing in reading

During reading, binocular visual input results in superior performance and is particularly important in the pre-processing of parafoveal text prior to direct fixation. It is not yet clear whether binocular vision in the parafovea is necessary for accurate saccadic targeting, or for efficient pre-processing of upcoming text, prior to direct fixation. In the present sentence reading experiment, we used a dichoptic gaze-contingent moving window paradigm in order to establish 1) how much parafoveal binocular input is necessary for fluent reading and 2) which aspect of parafoveal processing is more reliant on binocular vision. Eye movement measures revealed that reading was disrupted unless word N + 1 was entirely binocular in the parafovea, though no additional benefit was observed when word N + 2 was also binocular. Additionally, while fixation durations and reading times were clearly affected by the manipulation, similarly pronounced changes in binocular saccadic parameters such as accuracy, speed, amplitude and velocity were not observed. We concluded that the disruption to reading caused by presenting monocular text to the right of fixation cannot be attributed to difficulties in targeting binocular saccacdes, but instead results from a decreased efficiency in the pre-processing of parafoveal text. These results provide further demonstration for the importance of binocular vision during written text processing.

Event-related brain potentials reveal age-related changes in parafoveal-foveal integration during sentence processing

Normative aging is associated with deficits in visual acuity and cognitive control that impact the allocation of visual attention, but little is known about how those changes affect information extraction and integration during visual language comprehension in older adulthood. In the current study, we used a visual hemi-field flanker RSVP paradigm with event-related brain potentials to study how older readers process fine-grained aspects of semantic expectancy in parafoveal and foveal vision. Stimuli consisted of high constraint sentences with expected, unexpected but plausible, or anomalous parafoveal target words, as well as low constraint sentences with neutral but expected target words. Older adults showed graded parafoveal N400 effects that were strikingly similar to younger readers, indicating intact parafoveal semantic processing. However, whereas young adults were able to use this parafoveal pre-processing to facilitate subsequent foveal viewing, resulting in a reduced foveal N400 effect, older adults were not able to. Instead, older adults re-processed the semantics of words in foveal vision, resulting in a larger foveal N400 effect relative to the young. Collectively, our findings suggest that although parafoveal semantic processing per se is preserved in aging, there exists an age-related deficit in the ability to rapidly integrate parafoveal and foveal visual semantic representations.

The Inversion Effect for Chinese Characters is Modulated by Radical Organization

In studies of visual object recognition, strong inversion effects accompany the acquisition of expertise and imply the involvement of configural processing. Chinese literacy results in sensitivity to the orthography of Chinese characters. While there is some evidence that this orthographic sensitivity results in an inversion effect, and thus involves configural processing, that processing might depend on exact orthographic properties. Chinese character recognition is believed to involve a hierarchical process, involving at least two lower levels of representation: strokes and radicals. Radicals are grouped into characters according to certain types of structure, i.e. left-right structure, top-bottom structure, or simple characters with only one radical by itself. These types of radical structures vary in both familiarity, and in hierarchical level (compound versus simple characters). In this study, we investigate whether the hierarchical-level or familiarity of radical-structure has an impact on the magnitude of the inversion effect. Participants were asked to do a matching task on pairs of either upright or inverted characters with all the types of structure. Inversion effects were measured based on both reaction time and response sensitivity. While an inversion effect was observed in all 3 conditions, the magnitude of the inversion effect varied with radical structure, being significantly larger for the most familiar type of structure: characters consisting of 2 radicals organized from left to right. These findings indicate that character recognition involves extraction of configural structure as well as radical processing which play different roles in the processing of compound characters and simple characters.