Mislocated fixations can account for parafoveal-on-foveal effects in eye movements during reading

Contrasting predictions of serial and parallel views on the processing of foveal and parafoveal information during reading were tested. A high-frequency adjective (young) was followed by either a high-frequency word_n (child) or a low-frequency word_n (tenor), which in turn was followed by either a correct (performing) or an orthographic illegal word_{n + 1} (pxvforming) as a parafoveal preview. A limited parafoveal-on-foveal effect was observed: There were inflated fixation times on word_n when the preview of word_{n + 1} was orthographically illegal. However, this parafoveal-on-foveal effect was (a) independent of the frequency of word_n, (b) restricted to those instances when the eyes were very close to word_{n + 1}, and (c) associated with relatively long prior saccades. These observations are all compatible with a mislocated fixation account in which parafoveal-on-foveal effects result from saccadic undershoots of word_{n + 1} and with a serial model of eye movement control during reading.     

Spelling-sound regularity effects on eye fixations in reading

An interaction of word frequency and word regularity has typically been observed in naming and lexical decision experiments in which, in addition to an overall effect of word frequency, responses to low-frequency exception words are slower than those to low-frequency regular words, while no such difference occurs with high-frequency words. The only eye movement study to examine this effect in reading (Inhoff & Topolski, 1994) reported only transient effects of regularity. In the present experiment, we examined the frequency x regularity interaction using different stimuli than those of Inhoff and Topolski and also varied the parafoveal preview of the target word prior to fixation. When the preview was valid, the frequency x regularity interaction appeared. However, with an invalid preview, the effect of regularity disappeared. The results suggest that the activation of phonological codes is a very early component of reading.     

Emotion words affect eye fixations during reading

Emotion words are generally characterized as possessing high arousal and extreme valence and have typically been investigated in paradigms in which they are presented and measured as single words. This study examined whether a word's emotional qualities influenced the time spent viewing that word in the context of normal reading. Eye movements were monitored as participants read sentences containing an emotionally positive (e.g., lucky), negative (e.g., angry), or neutral (e.g., plain) word. Target word frequency (high or low) was additionally varied to help determine the temporal locus of emotion effects, with interactive results suggesting an early lexical locus of emotion processing. In general, measures of target fixation time demonstrated significant effects of emotion and frequency as well as an interaction. The interaction arose from differential effects with negative words that were dependent on word frequency. Fixation times on emotion words (positive or negative) were consistently faster than those on neutral words with one exception-high-frequency negative words were read no faster than their neutral counterparts. These effects emerged in the earliest eye movement measures, namely, first and single fixation duration, suggesting that emotionality, as defined by arousal and valence, modulates lexical processing. Possible mechanisms involved in processing emotion words are discussed, including automatic vigilance and desensitization, both of which imply a key role for word frequency. Finally, it is important that early lexical effects of emotion processing can be established within the ecologically valid context of fluent reading.     

Fast priming during eye fixations in reading.

Near-threshold primes were "flashed" in a target location prior to the onset of a target word while Ss read. The type and duration of the prime were manipulated. In Exp. 1, identical, related, and unrelated primes were presented for 60, 45, or 30 ms from onset of an eye fixation. The prime was then replaced with the target word, which remained in place while Ss finished reading the sentence. Fixation time on the target word was measured. Exp. 2 replicated Exp. 1, with two exceptions: A random letter string replaced the identical prime condition, and prime durations of 39, 30, or 21 ms were used. In both experiments, significant priming effects (related vs. unrelated) were obtained when the prime was presented for 30 ms. Results are discussed with regard to subliminal priming effects. Applications to the study of word recognition processes are also discussed.     

Inhibitory neighbor priming effects in eye movements during reading

We report an eye movement experiment investigating whether prior processing of a word’s orthographic neighbor in a sentence influences subsequent word processing during reading. There was greater difficulty in early word processing when a target word’s neighbor rather than a control word appeared earlier in a sentence; this effect was uninfluenced by the relative lexical frequency of the word and its neighbor. We discuss this inhibitory neighbor priming effect in terms of competitive network models of word recognition and the process of lexical identification in the E-Z Reader model of oculomotor control (e.g., Reichle, Pollatsek, Fisher, & Rayner, 1998).     

Saccadic eye movements during reading

Exposure duration and sequential redundancy are major determinants of report accuracy for textual displays. Increased emission of left-to-right saccades to both word strings and letter strings are associated with sequential redundancy. Such saccades are more frequent when words rather than pseudowords are viewed. The pattern of scanning is not simply left to right, and certain patterns of eye movements are associated positively with accuracy of report. These are a function of the sequential constraints of the display and are stronger for word strings than for letter strings. Presence of a word elicits more left-to-right saccades than does a pseudoword, even at exposures too short for a second fixation to be useful. In that case, there is no difference between redundant and nonredundant pseudowords. There is no redundancy effect at short exposures of pseudosentences.     

Lexical access during eye fixations in reading: effects of word-initial letter sequence

Two experiments tested the hypothesis that lexical access in reading is initiated on the basis of word-initial letter information obtainable in the parafoveal region. Eye movements were monitored while college students read sentences containing target words whose initial trigram (Experiment 1) or bigram (Experiment 2) imposed either a high or a low degree of constraint in the lexicon. In contradiction to our hypothesis, high-constraint words (e.g., DWARF) received longer fixations than did low-constraint words (e.g., CLOWN), despite the fact that high-constraint words have an initial letter sequence shared by few other words in the lexicon. Moreover, a comparison of fixation times in viewing conditions with and without parafoveal letter information showed that the amount of decrease in target fixation time due to prior parafoveal availability was the same for high-constraint and low-constraint targets. We concluded that increased familiarity of word-initial letter sequence is beneficial to lexical access and that familiarity affects the efficiency of foveal but not parafoveal processing.     

Activation of phonological codes during eye fixations in reading.

Two experiments addressed the issue of whether phonological codes are activated early in a fixation during reading using the fast-priming technique (S. C. Sereno & K. Rayner, 1992). Participants read sentences and, at the beginning of the initial fixation in a target location, a priming letter string was displayed, followed by the target word. Phonological priming was assessed by the difference in the gaze duration on the target word between when the prime was a homophone and when it was a control word equated with the homophone on orthographic similarity to the target. Both experiments demonstrated homophonic priming with prime durations of about 35 ms, but only for high-frequency word primes, indicating that lexicality was guiding the speed of the extraction of phonological codes early in a fixation. Evidence was also obtained for orthographic priming, and the data suggest that orthographic and phonological priming effects interact in a mutually facilitating manner.     

Linguistic focus affects eye movements during reading

In two experiments, we explored how readers encode information that is linguistically focused. Subjects read sentences in which a word or phrase was focused by a syntactic manipulation (Experiment 1) or by a preceding context (Experiment 2) while their eye movements were monitored. Readers had longer reading times while reading a region of the sentence that was focused than when the same region was not focused. The results suggest that readers encode focused information more carefully, either upon first encountering it or during a second-pass reading of it. We conclude that the enhanced memory representations for focused information found in previous studies may be due in part to differences in reading patterns for focused information.     

Covert attention and eye movements during reading

Eye movements were monitored during the reading of spatially transformed text in order to examine covert attentional processes in reading. In some conditions, the sequence of letters within a word was congruent with (i.e. in the same direction as) the sequence of words in the sentence; in other conditions the direction of letters within words and the direction of words in the sentence were incongruent. In addition, the window of visible text was varied so that in some conditions only the fixated word (and all preceding words) were visible, whereas in other conditions the fixated word and the succeeding word were both visible. Readers were able to extract more parafoveal information from text when the words themselves were normal than when the letters within the words were transformed. However, with practice, readers were able to use some parafoveal information even when the words were transformed. The most important finding was that the congruity of the word and letter order had no reliable effect on the ability to extract parafoveal information and influenced reading performance only when the words themselves were normal. We conclude that covert attention in reading is not a letter-by-letter scan that sweeps across the page, but either an asymmetric spotlight held constant on each fixation or a shifting of an attentional spotlight extending across multiletter units (possibly words) with the direction of shifts of attention closely coupled to the direction of eye movements.     

Masking of foveal and parafoveal vision during eye fixations in reading

A window or visual mask as moved across text in synchrony with the reader's eye movements. The size of the window or mask was varied so that either information in foveal or parafoveal vision was masked on each fixation. In another experiment, the onset of the mask was delayed for a certain amount of time following the end of the saccade. The results of the experiments point out the relative importance of foveal and parafoveal vision for reading and further indicate that most of the visual information necessary for reading can be acquired during the first 50 msec that information is available during an eye fixation.     

Reading strategy modulates parafoveal-on-foveal effects in sentence reading

Task demands and individual differences have been linked reliably to word skipping during reading. Such differences in fixation probability may imply a selection effect for multivariate analyses of eye-movement corpora if selection effects correlate with word properties of skipped words. For example, with fewer fixations on short and highly frequent words the power to detect parafoveal-on-foveal effects is reduced. We demonstrate that increasing the fixation probability on function words with a manipulation of the expected difficulty and frequency of questions reduces an age difference in skipping probability (i.e., old adults become comparable to young adults) and helps to uncover significant parafoveal-on-foveal effects in this group of old adults. We discuss implications for the comparison of results of eye-movement research based on multivariate analysis of corpus data with those from display-contingent manipulations of target words.     

Working memory and inferences: evidence from eye fixations during reading

Eye fixations during reading were monitored to examine the relationship between individual differences in working memory capacity-as assessed by the reading span task-and inferences about predictable events. Context sentences predicting likely events, or non-predicting control sentences, were presented. They were followed by continuation sentences in which a target word represented an event to be inferred (inferential word) or an unlikely event (non-predictable word). A main effect of reading span showed that high working memory capacity was related to shorter gaze durations across sentence regions. More specific findings involved an interaction between context, target, and reading span on late processing measures and regions. Thus, for high- but not for low-span readers, the predicting condition, relative to the control condition, facilitated reanalysis of the continuation sentence that represented the inference concept. This effect was revealed by a reduction in regression-path reading time in the last region of the sentence, involving less time reading that region and fewer regressions from it. These results indicate that working memory facilitates elaborative inferences during reading, but that this occurs at late text-integration processes, rather than at early lexical-access processes.     

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.     

Effects of syntactic prominence on eye movements during reading

Three experiments explored whether patterns of eye movements during reading might help explain syntactic prominence effects that are typically observed using reaction time tasks. Participants read sentences in which target words were in syntactically prominent or syntactically less prominent positions. Across all three experiments, using three types of syntactic prominence manipulations, there were fewer fixations and shorter reading times for words in more prominent positions, indicating that enhanced accessibility of syntactically prominent words is not caused by increased processing time. Rather, syntactic prominence appears to facilitate early encoding/lexical access and sentence integration processes while also, as shown previously, increasing activation of concepts in a comprehender’s sentence or discourse representation. We propose that enhanced encoding and sentence integration processes can be attributed to an increase in attentional resources for more prominent concepts, and that this increase derives from readers’ immediate sensitivity to informational prominence contours that are signaled by syntax.     

Inferences about predictable events: eye movements during reading

 Eye fixations were recorded to assess whether, how, and when readers draw inferences about predictable events. Predicting context sentences, or non-predicting control sentences, were presented, followed by continuation sentences in which a target word referred to a predictable event (inferential word) or an unlikely event (non-predictable word). There were no effects on initial target word processing measures, such as launch and landing sites, fixation probability, first-fixation duration, or first-pass reading time. However, relative to the control condition, the predicting context (1) speeded up reanalysis of the inferential word, as revealed by a reduction in second-pass reading time and regressions, and (2) interfered with processing of the non-predictable word, as shown by an increase in regressions. These results indicate that predictive inferences are active at late text integration processes, rather than at early lexical-access processes. The pattern of findings suggests that these inferences involve initial activation of rather general concepts following the inducing context, and that they are completed or refined with delay, after the inferential target word is read. Received: 4 January 2000 / Accepted: 23 October 2000     

The word grouping hypothesis and eye movements during reading

The distribution of landing positions and durations of first fixations in a region containing a noun preceded by either an article (e.g., the soldiers) or a high-frequency 3-letter word (e.g., all soldiers) were compared. Although there were fewer first fixations on the blank space between the high-frequency 3-letter word and the noun than on the surrounding letters (and the fixations on the blank space were shorter), this pattern did not occur when the noun was preceded by an article. R. Radach (1996) inferred from a similar experiment that did not manipulate the type of short word that 2 words could be processed as a perceptual unit during reading when the first word is a short word. As this different pattern of fixations is restricted to article-noun pairs, it indicates that word grouping does not occur purely on the basis of word length during reading; moreover, as the authors demonstrate, one can explain the observed patterns in both conditions more parsimoniously without adopting a word-grouping mechanism in eye movement control during reading.     

The orthographic uniqueness point and eye movements during reading

Recent research found that naming and lexical decision times for words with an early orthographic uniqueness point (OUP) were faster than for words with a late OUP ( Kwantes & Mewhort, 1999a ; Lindell, Nicholls, & Castles, 2003 ). A word's OUP corresponds to the letter position in the word where that word is differentiated from other words. These results have been presented as evidence for sequential letter processing in visual word recognition ( Kwantes & Mewhort, 1999a ). In two experiments, we attempted to extend these results to a more natural reading situation by recording participants’ eye movements. Readers read sentences with early or late OUP words embedded in them. In both experiments, we manipulated the amount of parafoveal information available during reading. Readers did not show any consistent benefit for reading words with an early OUP regardless of the amount of preview available. Our results are at odds with the naming and lexical decision data and prove problematic for models that predict OUP effects.     

Evidence for delayed parafoveal-on-foveal effects from word n+2 in reading

During reading information is acquired from word(s) beyond the word that is currently looked at. It is still an open question whether such parafoveal information can influence the current viewing of a word, and if so, whether such parafoveal-on-foveal effects are attributable to distributed processing or to mislocated fixations which occur when the eyes are directed at a parafoveal word but land on another word instead. In two display-change experiments, we orthogonally manipulated the preview and target difficulty of word n+2 to investigate the role of mislocated fixations on the previous word n+1. When the eyes left word n, an easy or difficult word n+2 preview was replaced by an easy or difficult n+2 target word. In Experiment 1, n+2 processing difficulty was manipulated by means of word frequency (i.e., easy high-frequency vs. difficult low-frequency word n+2). In Experiment 2, we varied the visual familiarity of word n+2 (i.e., easy lower-case vs. difficult alternating-case writing). Fixations on the short word n+1, which were likely to be mislocated, were nevertheless not influenced by the difficulty of the adjacent word n+2, the hypothesized target of the mislocated fixation. Instead word n+1 was influenced by the preview difficulty of word n+2, representing a delayed parafoveal-on-foveal effect. The results challenge the mislocated-fixation hypothesis as an explanation of parafoveal-on-foveal effects and provide new insight into the complex spatial and temporal effect structure of processing inside the perceptual span during reading.     

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.