Parafoveal Preprocessing Research Articles

The importance of the first letter in children’s parafoveal preprocessing in English: Is it phonologically or orthographically driven?

For both adult and child readers of English, the first letter of a word plays an important role in lexical identification. Using the boundary paradigm during silent sentence reading, we examined whether the first-letter bias in parafoveal preprocessing is phonologically or orthographically driven and whether this differs between skilled adult and beginner child readers. Participants read sentences that contained either a correctly spelled word in preview (identity; e.g., "circus"), a preview letter string that maintained the phonology but manipulated the orthography of the first letter (P + O- preview; e.g., "sircus"), or a preview letter string that manipulated both the phonology and the orthography of the first letter (P- O- preview; e.g., "wircus"). There was a cost associated with manipulating the first letter of the target words in preview for both adults and children. Critically, during first-pass reading, both adult and child readers displayed similar reading times between P + O- and P- O- previews. This shows that the first-letter bias is driven by orthographic encoding and that the first letter's orthographic code in preview is crucial for efficient, early processing of phonology. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Word frequency, predictability, and return-sweep saccades: Towards the modeling of eye movements during paragraph reading.

Models of eye movement control during reading focus on the reading of single lines of text. Within these models, word frequency and predictability are important input variables which influence fixation probabilities and durations. However, a comprehensive model of eye movement control will have to account for readers' eye movements across multiline texts. Line-initial words are unlike those presented midline; they are routinely unavailable for parafoveal preprocessing. Therefore, it is unclear whether and how word frequency and predictability influence reading times on line-initial words. To address this, we present an analysis of the Provo Corpus (Luke & Christianson, 2018) followed by a novel eye-movement experiment. We conclude that word frequency and predictability impact single-fixation and gaze durations on line-initial words. We also observed that return-sweep error (undersweep-fixations) may, among several other possibilities, allow for parafoveal processing of line-initial words prior to their direct fixation. Implications for models of eye movement control during reading are discussed. (PsycINFO Database Record (c) 2019 APA, all rights reserved).

No Effect of cathodal tDCS of the posterior parietal cortex on parafoveal preprocessing of words

The present study investigated the functional role of the posterior parietal cortex during the processing of parafoveally presented letter strings. To this end, we simultaneously presented two letter strings (word or pseudoword) – one foveally and one parafoveally – and asked the participants to indicate the presence of a word (i.e., lexical decision flanker task). We applied cathodal transcranial direct current stimulation (tDCS) over the posterior parietal cortex in order to establish causal links between brain activity and lexical decision performance (accuracy and latency). The results indicated that foveal stimulus difficulty affected the amount of parafoveally processed information. Bayes factor analysis showed no effects of brain stimulation suggesting that posterior parietal cathodal tDCS does not modulate attention-related processes during parafoveal preprocessing. This result is discussed in the context of recent tDCS studies on attention and performance.

Spill the load: Mixed evidence for a foveal load effect, reliable evidence for a spillover effect in eye-movement control during reading

It has been hypothesized that the processing difficulty of the fixated word (i.e., “foveal load”) modulates the amount of parafoveal preprocessing of the next word. Evidence for the hypothesis has been provided by the application of parafoveal masks within the boundary paradigm. Other studies that applied alternative means of manipulating the parafoveal preview (i.e., visual degradation) could not replicate the effect of foveal load. The present study examined the effect of foveal load by directly comparing the application of parafoveal masks (Exp. 1) with the alternative manipulation of visually degrading the parafoveal preview (Exp. 2) in adult readers. Contrary to expectation, we did not find the foveal-load interaction in the first experiment with traditional letter masks. We did, however, find the expected interaction in the second experiment with visually degraded previews. Both experiments revealed a spillover effect indicating that the processing of a word is not (always) fully completed when the reader already fixates the next word (i.e., processing “spills over” to the next word). The implications for models of eye-movement control in reading are discussed.

An investigation of parafoveal masks with the incremental boundary paradigm.

Most of what we know about parafoveal preprocessing during reading is based on the boundary paradigm in combination with parafoveal masks as a presumably neutral baseline condition. Recent evidence questions the neutrality of the baseline condition by showing that parafoveal masks inflict preview costs. Using a novel, incremental boundary paradigm we studied the effect of parafoveal masks. Manipulating the salience of parafoveal previews, we found that increasing salience of the masks resulted in increasingly longer fixation times on target words, but also on pretarget words—suggesting preview costs. We conclude that the hidden preview costs of parafoveal masks in the classical boundary paradigm inflate the processing times for the baseline condition and hence lead to an overestimation of the preview benefit. Thus, the present study questions the validity of some of the conclusions drawn on the basis of the classical boundary paradigm.

Processing of parafoveally presented words. An fMRI study

The present fMRI study investigated neural correlates of parafoveal preprocessing during reading and the type of information that is accessible from the upcoming - not yet fixated - word. Participants performed a lexical decision flanker task while the constraints imposed by the first three letters (the initial trigram) of parafoveally presented words were controlled. Behavioral results evidenced that the amount of information extracted from parafoveal stimuli, was affected by the difficulty of the foveal stimulus. Easy to process foveal stimuli (i.e., high frequency nouns) allowed parafoveal information to be extracted up to the lexical level. Conversely, when foveal stimuli were difficult to process (orthographically legal nonwords) only constraining trigrams modulated the task performance. Neuroimaging findings showed no effects of lexicality (i.e., difference between words and pseudowords) in the parafovea independently from the difficulty of the foveal stimulus. The constraints imposed by the initial trigrams, however, modulated the hemodynamic response in the left supramarginal gyrus. We interpreted the supramarginal activation as reflecting sublexical (phonological) processes. The missing parafoveal lexicality effect was discussed in relation to findings of experiments which observed effects of parafoveal semantic congruency on electrophysiological correlates.

Phonological processing during silent reading in teenagers who are deaf/hard of hearing: an eye movement investigation.

There has been considerable variability within the literature concerning the extent to which deaf/hard of hearing individuals are able to process phonological codes during reading. Two experiments are reported in which participants' eye movements were recorded as they read sentences containing correctly spelled words (e.g., church), pseudohomophones (e.g., cherch), and spelling controls (e.g., charch). We examined both foveal processing and parafoveal pre-processing of phonology for three participant groups-teenagers with permanent childhood hearing loss (PCHL), chronological age-matched controls, and reading age-matched controls. The teenagers with PCHL showed a pseudohomophone advantage from both directly fixated words and parafoveal preview, similar to their hearing peers. These data provide strong evidence for phonological recoding during silent reading in teenagers with PCHL.

Foveal processing difficulty does not affect parafoveal preprocessing in young readers

Recent evidence suggested that parafoveal preprocessing develops early during reading acquisition, that is, young readers profit from valid parafoveal information and exhibit a resultant preview benefit. For young readers, however, it is unknown whether the processing demands of the currently fixated word modulate the extent to which the upcoming word is parafoveally preprocessed – as it has been postulated (for adult readers) by the foveal load hypothesis. The present study used the novel incremental boundary technique to assess whether 4th and 6th Graders exhibit an effect of foveal load. Furthermore, we attempted to distinguish the foveal load effect from the spillover effect. These effects are hard to differentiate with respect to the expected pattern of results, but are conceptually different. The foveal load effect is supposed to reflect modulations of the extent of parafoveal preprocessing, whereas the spillover effect reflects the ongoing processing of the previous word whilst the reader’s fixation is already on the next word. The findings revealed that the young readers did not exhibit an effect of foveal load, but a substantial spillover effect. The implications for previous studies with adult readers and for models of eye movement control in reading are discussed.

Using a dichoptic moving window presentation technique to investigate binocular advantages during reading.

Reading comes with a clear binocular advantage, expressed in shorter fixation times and fewer regressions in binocular relative to monocular visual presentations. Little is known, however, about whether the cost associated with monocular viewing derives primarily from the encoding of foveal information or in obtaining a preview benefit from upcoming parafoveal text. In the present sentence reading eye tracking experiment, the authors used a novel dichoptic binocular gaze-contingent moving window technique to selectively manipulate the amount of text made available to the reader both binocularly and monocularly in the fovea and parafovea on a fixation-by-fixation basis. This technique allowed the authors to quantify disruption to reading caused by prevention of binocular fusion during direct fixation of words and parafoveal preprocessing of upcoming text. Sentences were presented (a) binocularly; (b) monocularly; (c) with monocular text to the left of fixation; (d) with monocular text to the right of fixation; or (e) with all words other than the fixated word presented binocularly. A robust binocular advantage occurred for average fixation duration and regressions. Also, while there was a limited cost associated with monocular foveal processing, the restriction of parafoveal processing to monocular information was particularly disruptive. The findings demonstrate the critical importance of a unified binocular input for the efficient preprocessing text to the right of fixation. (PsycINFO Database Record

On the Development of Parafoveal Preprocessing: Evidence from the Incremental Boundary Paradigm

Parafoveal preprocessing of upcoming words and the resultant preview benefit are key aspects of fluent reading. Evidence regarding the development of parafoveal preprocessing during reading acquisition, however, is scarce. The present developmental (cross-sectional) eye tracking study estimated the magnitude of parafoveal preprocessing of beginning readers with a novel variant of the classical boundary paradigm. Additionally, we assessed the association of parafoveal preprocessing with several reading-related psychometric measures. The participants were children learning to read the regular German orthography with about 1, 3, and 5 years of formal reading instruction (Grade 2, 4, and 6, respectively). We found evidence of parafoveal preprocessing in each Grade. However, an effective use of parafoveal information was related to the individual reading fluency of the participants (i.e., the reading rate expressed as words-per-minute) which substantially overlapped between the Grades. The size of the preview benefit was furthermore associated with the children’s performance in rapid naming tasks and with their performance in a pseudoword reading task. The latter task assessed the children’s efficiency in phonological decoding and our findings show that the best decoders exhibited the largest preview benefit.

Corrigendum to “Do successor effects in reading reflect lexical parafoveal processing? Evidence from corpus-based and experimental eye movement data” [J. Mem. Lang. 79–80 (2015) 76–96

In the past, most research on eye movements during reading involved a limited number of subjects reading sentences with specific experimental manipulations on target words. Such experiments usually only analyzed eye-movements measures on and around the target word. Recently, some researchers have started collecting larger data sets involving large and diverse groups of subjects reading large numbers of sentences, enabling them to consider a larger number of influences and study larger and more representative subject groups. In such corpus studies, most of the words in a sentence are analyzed. The complexity of the design of corpus studies and the many potentially uncontrolled influences in such studies pose new issues concerning the analysis methods and interpretability of the data. In particular, several corpus studies of reading have found an effect of successor word (n + 1) frequency on current word (n) fixation times, while studies employing experimental manipulations tend not to. The general interpretation of corpus studies suggests that readers obtain parafoveal lexical information from the upcoming word before they have finished identifying the current word, while the experimental manipulations shed doubt on this claim. In the present study, we combined a corpus analysis approach with an experimental manipulation (i.e., a parafoveal modification of the moving mask technique, Rayner & Bertera, 1979), so that, either (a) word n + 1, (b) word n + 2, (c) both words, or (d) neither word was masked. We found that denying preview for either or both parafoveal words increased average fixation times. Furthermore, we found successor effects similar to those reported in the corpus studies. Importantly, these successor effects were found even when the parafoveal word was masked, suggesting that apparent successor frequency effects may be due to causes that are unrelated to lexical parafoveal preprocessing. We discuss the implications of this finding both for parallel and serial accounts of word identification and for the interpretability of large correlational studies of word identification in reading in general.

An incremental boundary study on parafoveal preprocessing in children reading aloud: Parafoveal masks overestimate the preview benefit

Parafoveal preprocessing is an important factor for efficient reading and, in eye-movement studies, is typically investigated by means of parafoveal masking: Valid previews are compared to instances in which masks prevent preprocessing. A long-held assumption was that parafoveal preprocessing, as assessed by this technique, only reflects facilitation (i.e., a preview benefit). Recent studies, however, suggested that the benefit estimate is inflated due to interference of the parafoveal masks, i.e., the masks inflict processing costs. With children from Grades 4 and 6, we administered the novel incremental priming technique. The technique manipulates the salience of the previews by systematically varying its perceptibility (i.e., by visually degrading the previews). This technique does not require a baseline condition, but makes it possible to determine whether a preview induces facilitation or interference. Our salience manipulation of valid previews revealed a preview benefit in the children of both Grades. For two commonly used parafoveal masks, we observed interference corroborating the notion that masks are not a proper baseline. With the novel incremental boundary technique, in contrast, one can achieve an accurate estimate of the preview benefit.

Do successor effects in reading reflect lexical parafoveal processing? Evidence from corpus-based and experimental eye movement data

In the past, most research on eye movements during reading involved a limited number of subjects reading sentences with specific experimental manipulations on target words. Such experiments usually only analyzed eye-movements measures on and around the target word. Recently, some researchers have started collecting larger data sets involving large and diverse groups of subjects reading large numbers of sentences, enabling them to consider a larger number of influences and study larger and more representative subject groups. In such corpus studies, most of the words in a sentence are analyzed. The complexity of the design of corpus studies and the many potentially uncontrolled influences in such studies pose new issues concerning the analysis methods and interpretability of the data. In particular, several corpus studies of reading have found an effect of successor word (n + 1) frequency on current word (n) fixation times, while studies employing experimental manipulations tend not to. The general interpretation of corpus studies suggests that readers obtain parafoveal lexical information from the upcoming word before they have finished identifying the current word, while the experimental manipulations shed doubt on this claim. In the present study, we combined a corpus analysis approach with an experimental manipulation (i.e., a parafoveal modification of the moving mask technique, Rayner & Bertera, 1979), so that, either (a) word n + 1, (b) word n + 2, (c) both words, or (d) neither word was masked. We found that denying preview for either or both parafoveal words increased average fixation times. Furthermore, we found successor effects similar to those reported in the corpus studies. Importantly, these successor effects were found even when the parafoveal word was masked, suggesting that apparent successor frequency effects may be due to causes that are unrelated to lexical parafoveal preprocessing. We discuss the implications of this finding both for parallel and serial accounts of word identification and for the interpretability of large correlational studies of word identification in reading in general.

Parafoveal preprocessing in reading revisited: Evidence from a novel preview manipulation.

The study investigated parafoveal preprocessing by the means of the classical invisible boundary paradigm and a novel manipulation of the parafoveal previews (i.e., visual degradation). Eye movements were investigated on 5-letter target words with constraining (i.e., highly informative) initial letters or similarly constraining final letters. Visual degradation was administered to all, no, the initial, or the final 2 letters of the parafoveal preview of the target words. Critically, the manipulation of the parafoveal previews did not interfere with foveal processing. Thus, we had a proper baseline to which we could relate our main findings, which were as follows: First, the valid (i.e., nondegraded) preview of the target words' final letters led to shorter fixation times compared to the baseline condition (i.e., the degradation of all letters). Second, this preview benefit for the final letters was comparable to the benefit of previewing the initial letters. Third, the preview of a constraining initial letter sequence, however, yielded a larger preview benefit than the preview of an unconstraining initial letter sequence. The latter finding indicates that preprocessing constraining initial letters is particularly conducive to foveal word recognition.

Parafoveal X-masks interfere with foveal word recognition: evidence from fixation-related brain potentials.

The boundary paradigm, in combination with parafoveal masks, is the main technique for studying parafoveal preprocessing during reading. The rationale is that the masks (e.g., strings of X's) prevent parafoveal preprocessing, but do not interfere with foveal processing. A recent study, however, raised doubts about the neutrality of parafoveal masks. In the present study, we explored this issue by means of fixation-related brain potentials (FRPs). Two FRP conditions presented rows of five words. The task of the participant was to judge whether the final word of a list was a “new” word, or whether it was a repeated (i.e., “old”) word. The critical manipulation was that the final word was X-masked during parafoveal preview in one condition, whereas another condition presented a valid preview of the word. In two additional event-related brain potential (ERP) conditions, the words were presented serially with no parafoveal preview available; in one of the conditions with a fixed timing, in the other word presentation was self-paced by the participants. Expectedly, the valid-preview FRP condition elicited the shortest processing times. Processing times did not differ between the two ERP conditions indicating that “cognitive readiness” during self-paced processing can be ruled out as an alternative explanation for differences in processing times between the ERP and the FRP conditions. The longest processing times were found in the X-mask FRP condition indicating that parafoveal X-masks interfere with foveal word recognition.

Trans-saccadic parafoveal preview benefits in fluent reading: A study with fixation-related brain potentials

During natural reading, a parafoveal preview of the upcoming word facilitates its subsequent recognition (e.g., shorter fixation durations compared to masked preview) but nothing is known about the neural correlates of this so-called preview benefit. Furthermore, while the evidence is strong that readers preprocess orthographic features of upcoming words, it is controversial whether word meaning can also be accessed parafoveally. We investigated the timing, scope, and electrophysiological correlates of parafoveal information use in reading by simultaneously recording eye movements and fixation-related brain potentials (FRPs) while participants read word lists fluently from left to right. For one word-the target-(e.g., "blade") parafoveal information was manipulated by showing an identical ("blade"), semantically related ("knife"), or unrelated ("sugar") word as preview. In boundary trials, the preview was shown parafoveally but changed to the correct target word during the incoming saccade. Replicating classic findings, target words were fixated shorter after identical previews. In the EEG, this benefit was reflected in an occipitotemporal preview positivity between 200 and 280 ms. In contrast, there was no facilitation from related previews. In parafoveal-on-foveal trials, preview and target were embedded at neighboring list positions without a display change. Consecutive fixation of two related words produced N400 priming effects, but only shortly (160 ms) after the second word was directly fixated. Results demonstrate that neural responses to words are substantially altered by parafoveal preprocessing under normal reading conditions. We found no evidence that word meaning contributes to these effects. Saccade-contingent display manipulations can be combined with EEG recordings to study extrafoveal perception in vision.

Parafoveal processing of prefixed words during eye fixations in reading: evidence against morphological influences on parafoveal preprocessing.

Two eye movement experiments were conducted to investigate whether the morphological constituents of a prefixed word influenced early word processing when English was read. Participants read sentences containing free-stem, bound-stem, or pseudoprefixed words, and the availability of the prefixed word morphemes in the parafovea was manipulated. Although preview benefit was greatest for the entire word, there was evidence that subsequent word processing was facilitated in both the prefix-only and the stem-only conditions. This effect was not influenced by word type. There was no evidence that morphological preprocessing occurred when morphological information was available in the parafovea. In addition, reading times for the target word did not differ for the different word types. Thus, there was no evidence to suggest that morphological constituents influence early word processing during reading. It is possible that morphological effects tend to be obscured when examined within a sentence context (although this phenomenon may be specific to English).

The influence of parafoveal preprocessing and linguistic context on the optimal landing position effect

Several experiments have shown the existence of an optimal landing position effect during isolated word recognition as well as during text reading; both the probability of refixating the test word and the gaze duration are smaller if the eye first fixates near the center of the word than if the eye first fixates other positions in the word. However, recent data indicate that the optimal landing position effect is weakened under normal reading conditions, when words are included in texts. The purpose of the present experiment was to test whether parafoveal preprocessing or linguistic context specific to the text reading situation could be responsible for this weakening. With a paradigm that approximates normal reading, albeit in a somewhat slower manner, it was shown that although the possibility of preprocessing words in parafoveal vision and of predicting them from preceding context globally affected refixation probability and gaze duration on the word, this did not strongly affect the optimal landing position effect. Since the global effects of these factors were comparable to those found by other authors in normal reading, it was concluded that the weakening of the optimal landing position effect during text reading results from the influence of other factors peculiar to this situation. Hypotheses are proposed as explanations of the effects of the manipulated factors on oculomotor behavior.