Boundary Paradigm Research Articles

Why does removing inter-word spaces produce reading deficits? The role of parafoveal processing.

To examine the role of inter-word spaces during reading, we used a gaze-contingent boundary paradigm to manipulate parafoveal preview (i.e., valid vs. invalid preview) in a normal text condition that contained spaces (e.g., "John decided to sell the table") and in an unsegmented text condition that contained random numbers instead of spaces (e.g.,"John4decided8to5sell9the7table"). Preview effects on mean first-fixation durations were larger for normal than unsegmented text conditions, and survival analyses revealed a delay in the onset of both preview validity and word-frequency effects on first-fixation durations for unsegmented relative to normal text. Taken together with simulations that were conducted using the E-Z Reader model, the present findings indicated that unsegmented text deficits reflect disruptions to both parafoveal processing and lexical processing. We discuss the implications of our results for models of eye-movement control.

Parafoveal processing in silent and oral reading: Reading mode influences the relative weighting of phonological and semantic information in Chinese.

We examined how reading mode (i.e., silent vs. oral reading) influences parafoveal semantic and phonological processing during the reading of Chinese sentences, using the gaze-contingent boundary paradigm. In silent reading, we found in 2 experiments that reading times on target words were shortened with semantic previews in early and late processing, whereas phonological preview effects mainly occurred in gaze duration or second-pass reading. In contrast, results showed that phonological preview information is obtained early on in oral reading. Strikingly, in oral reading, we observed a semantic preview cost on the target word in Experiment 1 and a decrease in the effect size of preview benefit from first- to second-pass measures in Experiment 2, which we hypothesize to result from increased preview duration. Taken together, our results indicate that parafoveal semantic information can be obtained irrespective of reading mode, whereas readers more efficiently process parafoveal phonological information in oral reading. We discuss implications for notions of information processing priority and saccade generation during silent and oral reading. (PsycINFO Database Record

A dear enemy relationship in a territorial cichlid: evidence for the threat-level hypothesis

Despite competing for resources such as space, food and mates, many territorial animals are less aggressive towards neighbours who rarely go beyond their territorial boundaries. This so-called dear enemy phenomenon is advantageous in territorial defence, but it has not been well studied in fish. In this work, we tested the ‘correct–incorrect boundary paradigm’ of the dear enemy phenomenon using the territorial cichlid fishNeolamprologus pulcher, which exhibits dear enemy relationships. When the fish was placed in a small experimental tank, in which fish established its territory, it was initially very aggressive against a neighbouring fish in an adjacent tank, but the aggression level decreased rapidly (within 4 days). When the tank containing the neighbour was shifted to the opposite side, the focal fish was more aggressive than the day before, but it exhibited less aggression than it did against a stranger placed on the shifted side. This lower level of aggression suggested that the focal fish did not regard the shifted neighbour as a stranger. Our observations provide support for the threat-level hypothesis, according to which territory owners will modulate aggression intensity based on the threat level.

Is semantic preview benefit due to relatedness or plausibility?

There is increasing evidence that skilled readers of English benefit from processing a parafoveal preview of a semantically related word. However, in previous investigations of semantic preview benefit using the gaze-contingent boundary paradigm the semantic relatedness between the preview and target has been confounded with the plausibility of the preview word in the sentence. In the present study, preview relatedness and plausibility were independently manipulated in neutral sentences read by a large sample of skilled adult readers. Participants were assessed on measures of reading and spelling ability to identify possible sources of individual differences in preview effects. The results showed that readers benefited from a preview of a plausible word, regardless of the semantic relatedness of the preview and the target. However, there was limited evidence of a semantic relatedness benefit when the plausibility of the preview was controlled. The plausibility preview benefit was strongest for low proficiency readers, suggesting that poorer readers were more likely to program a forward saccade based on information extracted from the preview. High proficiency readers showed equivalent disruption from all nonidentical previews suggesting that they were more likely to suffer interference from the orthographic mismatch between preview and target. (PsycINFO Database Record

Semantic preview benefit in English: Individual differences in the extraction and use of parafoveal semantic information.

Although there is robust evidence that skilled readers of English extract and use orthographic and phonological information from the parafovea to facilitate word identification, semantic preview benefits have been elusive. We sought to establish whether individual differences in the extraction and/or use of parafoveal semantic information could account for this discrepancy. Ninety-nine adult readers who were assessed on measures of reading and spelling ability read sentences while their eye movements were recorded. The gaze-contingent boundary paradigm was used to manipulate the availability of relevant semantic and orthographic information in the parafovea. On average, readers showed a benefit from previews high in semantic feature overlap with the target. However, reading and spelling ability yielded opposite effects on semantic preview benefit. High reading ability was associated with a semantic preview benefit that was equivalent to an identical preview on first-pass reading. High spelling ability was associated with a reduced semantic preview benefit despite an overall higher rate of skipping. These results suggest that differences in the magnitude of semantic preview benefits in English reflect constraints on extracting semantic information from the parafovea and competition between the orthographic features of the preview and the target. (PsycINFO Database Record

Parafoveal lexical activation depends on skilled reading proficiency.

The boundary paradigm was used to investigate individual differences in the extraction of lexical information from the parafovea in sentence reading. The preview of a target word was manipulated so that it was identical (e.g., sped), a higher frequency orthographic neighbor (seed), a nonword neighbor (sted), or an all-letter-different nonword (glat). Ninety-four skilled adult readers were assessed on measures of reading and spelling ability. The results showed that null effects of preview lexical status in the average data obscured systematic differences on the basis of proficiency and target neighborhood density. For targets from dense neighborhoods, inhibition from a higher frequency neighbor preview occurred among highly proficient readers, and particularly those with superior spelling ability, in early fixation measures. Poorer readers showed inhibition only in second-pass reading of the target. These data suggest that readers with precise lexical representations are more likely to extract lexical information from a word before it is fixated. The implications for computational models of eye movements in reading are discussed.

Parafoveal preview benefit is modulated by the precision of skilled readers' lexical representations.

In skilled reading, the processing of an upcoming word often begins in the parafovea, that is, before the word is fixated. This study investigated whether the extraction and use of multiple sources of information about an upcoming word depends on reading skill. The eye movements of 107 skilled adult readers, assessed on measures of reading and spelling ability, were recorded. The gaze-contingent boundary paradigm was used to manipulate the preview of a target word's identity and length in sentences with low- or high-frequency pretarget words. Across all first-pass reading measures, superior reading ability was associated with a larger preview benefit, but only among readers with high spelling ability, suggesting that the orthographic precision of a reader's stored lexical representations influences the extraction of parafoveal information. There was also evidence that the highly skilled reader/spellers' parafoveal processing advantage derived partly from their efficient foveal processing. Finally, in first fixations on the target, increased preview benefit for highly skilled reader/spellers was restricted to accurate length previews, suggesting that readers with precise lexical representations use upcoming word length in combination with parafoveal orthographic information to narrow down potential lexical candidates. The implications of these results for computational models of eye movements are discussed.

Parafoveal processing affects outgoing saccade length during the reading of Chinese.

Participants' eye movements were measured while reading Chinese sentences in which target-word frequency and the availability of parafoveal processing were manipulated using a gaze-contingent boundary paradigm. The results of this study indicate that preview availability and its interaction with word frequency modulated the length of the saccades exiting the target words, suggesting important functional roles for parafoveal processing in determining where the eyes move during reading. The theoretical significance of these findings is discussed in relation to 2 current models of eye-movement control during reading, both of which assume that saccades are directed toward default targets (e.g., the center of the next unidentified word). A possible method for addressing these limitations (i.e., dynamic attention allocation) is also discussed.

Preview benefit in English spaced compounds.

In an eye tracking experiment during reading we examined whether preview benefit could be observed from 2 words to the right of the currently fixated word if that word was the 2nd constituent of a spaced compound. The boundary paradigm (Rayner, 1975) was used to orthogonally manipulate whether participants saw an identity or nonword preview of the 1st (e.g., teddy) and 2nd constituent (e.g., bear) of a spaced compound located immediately beyond the boundary, respectively, words n + 1 and n + 2. Linear mixed-effects models revealed that participants gained an n + 2 preview benefit, such that they spent less time fixated on word n + 1 when given an identity preview of word n + 2. However, this effect was only observed if there was also an identity preview of word n + 1. Our findings suggest that the 2 constituent words of spaced compounds are processed as part of a larger lexical unit during natural reading.

The effects of character transposition within and across words in Chinese reading.

Given the lack of spaces between words in Chinese text, Chinese readers must parse these characters into words using their word knowledge. In this situation, are the characters belonging to a single word or to different words understood via different character-order encoding processes? In this study, we explored the effects of word boundaries in Chinese text on character-order encoding. We used four-character words (the one-word condition) and two two-character words (the two-word condition) as our targets. We embedded the target words into sentences and then manipulated the previews of the words using the boundary paradigm. The preview was identical to the target word (identity condition), had the two middle characters of the target word transposed (TC condition), or had two middle characters that were different from those in the target word (SC condition). Fixation durations on the target word in the TC condition were much longer than those in the identity condition for the two-word condition, but they were not significantly different for the one-word condition. Furthermore, for the one-word condition, gaze durations were longer in the SC than in the TC condition, whereas for the two-word condition, the difference between the TC and SC conditions was not significant. Word boundaries were found to affect the character-order encoding in Chinese reading, further suggesting the early occurrence of word segmentation.

Saccade target selection in Chinese reading.

In Chinese reading, there are no spaces to mark the word boundaries, so Chinese readers cannot target their saccades to the center of a word. In this study, we investigated how Chinese readers decide where to move their eyes during reading. To do so, we introduced a variant of the boundary paradigm in which only the target stimulus remained on the screen, displayed at the saccade landing site, after the participant's eyes crossed an invisible boundary. We found that when the saccade target was a word, reaction times in a lexical decision task were shorter when the saccade landing position was closer to the end of that word. These results are consistent with the predictions of a processing-based strategy to determine where to move the eyes. Specifically, this hypothesis assumes that Chinese readers estimate how much information is processed in parafoveal vision and saccade to a location that will carry novel information.

Assessing health in agriculture--towards a common research framework for soils, plants, animals, humans and ecosystems.

In agriculture and food systems, health-related research includes a vast diversity of topics. Nutritional, toxicological, pharmacological, epidemiological, behavioural, sociological, economic and political methods are used to study health in the five domains of soils, plants, livestock, humans and ecosystems. An idea developed in the early founding days of organic agriculture stated that the health of all domains is one and indivisible. Here we show that recent research reveals the existence and complex nature of such health links among domains. However, studies of health aspects in agriculture are often separated by disciplinary boundaries. This restrains the understanding of health in agricultural systems. Therefore we explore the opportunities and limitations of bringing perspectives together from the different domains. We review current approaches to define and assess health in agricultural contexts, comparing the state of the art of commonly used approaches and bringing together the presently disconnected debates in soil science, plant science, veterinary science and human medicine. Based on a qualitative literature analysis, we suggest that many health criteria fall into two paradigms: (1) the Growth Paradigm, where terms are primarily oriented towards continued growth; (2) the Boundary Paradigm, where terms focus on maintaining or coming back to a status quo, recognising system boundaries. Scientific health assessments in agricultural and food systems need to be explicit in terms of their position on the continuum between Growth Paradigm and Boundary Paradigm. Finally, we identify areas and concepts for a future direction of health assessment and research in agricultural and food systems.

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

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

Lack of semantic parafoveal preview benefit in reading revisited.

In contrast to earlier research, evidence for semantic preview benefit in reading has been reported by Hohenstein and Kliegl (Experimental Psychology: Learning, Memory, and Cognition, 40, 166-190, 2013) in an alphabetic writing system; they also implied that prior demonstrations of lack of a semantic preview benefit needed to be reexamined. In the present article, we report a rather direct replication of an experiment reported by Rayner, Balota, and Pollatsek (Canadian Journal of Psychology, 40, 473-483, 1986). Using the gaze-contingent boundary paradigm, subjects read sentences that contained a target word (razor), but different preview words were initially presented in the sentence. The preview was identical to the target word (i.e., razor), semantically related to the target word (i.e., blade), semantically unrelated to the target word (i.e., sweet), or a visually similar nonword (i.e., razar). When the reader's eyes crossed an invisible boundary location just to the left of the target word location, the preview changed to the target word. Like Rayner et al. (Canadian Journal of Psychology, 40, 473-483, 1986), we found that fixations on the target word were significantly shorter in the identical condition than in the unrelated condition, which did not differ from the semantically related condition; when an orthographically similar preview had been initially present in the sentence, fixations were shorter than when a semantically unrelated preview had been present. Thus, the present experiment replicates the earlier data reported by Rayner et al. (Canadian Journal of Psychology, 40, 473-483, 1986), indicating evidence for an orthographic preview benefit but a lack of semantic preview benefit in reading English.

Semantic preview benefit during reading.

Word features in parafoveal vision influence eye movements during reading. The question of whether readers extract semantic information from parafoveal words was studied in 3 experiments by using a gaze-contingent display change technique. Subjects read German sentences containing 1 of several preview words that were replaced by a target word during the saccade to the preview (boundary paradigm). In the 1st experiment the preview word was semantically related or unrelated to the target. Fixation durations on the target were shorter for semantically related than unrelated previews, consistent with a semantic preview benefit. In the 2nd experiment, half the sentences were presented following the rules of German spelling (i.e., previews and targets were printed with an initial capital letter), and the other half were presented completely in lowercase. A semantic preview benefit was obtained under both conditions. In the 3rd experiment, we introduced 2 further preview conditions, an identical word and a pronounceable nonword, while also manipulating the text contrast. Whereas the contrast had negligible effects, fixation durations on the target were reliably different for all 4 types of preview. Semantic preview benefits were greater for pretarget fixations closer to the boundary (large preview space) and, although not as consistently, for long pretarget fixation durations (long preview time). The results constrain theoretical proposals about eye movement control in reading. (PsycINFO Database Record (c) 2013 APA, all rights reserved).

Semantic preview benefit in reading English: The effect of initial letter capitalization.

A major controversy in reading research is whether semantic information is obtained from the word to the right of the currently fixated word (word n + 1). Although most evidence has been negative in English, semantic preview benefit has been observed for readers of Chinese and German. In the present experiment, we investigated whether the discrepancy between English and German may be attributable to a difference in visual properties of the orthography: the first letter of a noun is always capitalized in German, but is only occasionally capitalized in English. This visually salient property may draw greater attention to the word during parafoveal preview and thus increase preview benefit generally (and lead to a greater opportunity for semantic preview benefit). We used English target nouns that can either be capitalized (e.g., We went to the critically acclaimed Ballet of Paris while on vacation.) or not (e.g., We went to the critically acclaimed ballet that was showing in Paris.) and manipulated the capitalization of the preview accordingly, to determine whether capitalization modulates preview benefit in English. The gaze-contingent boundary paradigm was used with identical, semantically related, and unrelated previews. Consistent with our hypothesis, we found numerically larger preview benefits when the preview/target was capitalized than when it was lowercase. Crucially, semantic preview benefit was not observed when the preview/target word was not capitalized, but was observed when the preview/target word was capitalized.

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.

Preview Benefits and Word Segmentations When Reading Chinese

Recently, a number of studies have confirmed that Chinese readers could obtain linguistic information from word n+1 when it was in parafoveal vision. However, there was no confirmation that Chinese readers could obtain preview benefits from word n+2 (Yan, et. al., 2009; Yang, et. al., 2009; Yen, et. al., 2009; Rayner, et. al., 2003). The preview benefit effects received in a boundary paradigm could not exclude the effects of word segmentation. Therefore, there is no evidence that Chinese readers process the meaning of word n+1 by the word unit. Two experiments were conducted using a new eye-movement contingent display technology to clarify the confusion in the present study. The Chinese sentences used in both experiments consisted of 7 to 10 two-character words. There were four treatments of Chinese sentences in Experiment 1. Namely, as the nth word was fixated, (1) the words located to the right were all masked by a series of ※, (2) the words located to the right of the n+1th word were all masked by a series of ※ , (3) only the n+1th word was masked by two masks of ※, or (4) no words were masked as a baseline comparison (the control). Among the treatments, the first and third provided the cues of word n segmentation, and the second treatment provided information of word n+1 segmentation. Moreover, the first treatment was deprived of the preview benefit effects from word n+1 and n+2, the second treatment was deprived of the preview benefit effects from word n+2, and the third treatment was deprived of the preview benefit effects from n+1. An eye-movement apparatus was used, and eye-motion indices were measured. The effects on the total reading time, mean fixation duration, mean gaze duration, probability of refixation and word skipping were significant (p0.05). The differences among the second and third treatments and the control for these indices showed significant preview effects on word n+1 and n+2. The mean gaze duration in the second treatment was observed to be less than the control, although the total reading timeincreased. However, we cannot exclude the effect of the mask paradigm itself, which influenced the patterns of eye movements and affected the results of Experiment 1. Therefore, a second experiment was conducted. Experiment 2 adopted similar treatments as Experiment 1, but the two adjacent characters that did not belong to a word were masked together. The manipulations did not provide cues to facilitate word segmentation. Consequently, all the masked treatments in Experiment 2 influenced the total reading and fixation times more significantly than those in Experiment 1. The mean gaze duration in the second treatment was greater than the control, which was an opposite result to that of Experiment 1. The patterns of eye movements in Experiment 2 differed from those in Experiment 1. Thus, the results obtained in Experiment 1 were not because of the influence of the mask paradigm. Because the second treatment in Experiment 1 emphasized the boundary of word n+1, the differences in the eye movement patterns between this condition and the control revealed that the beneficial effects from the text in word n+1 were based on the word unit. Thus, the data from the current experiment better fit with the theoretical assumptions of parallel processing models in reading.

Orthographic and Phonological Preview Benefits: Parafoveal Processing in Skilled and Less-Skilled Deaf Readers

Many deaf individuals do not develop the high-level reading skills that will allow them to fully take part into society. To attempt to explain this widespread difficulty in the deaf population, much research has honed in on the use of phonological codes during reading. The hypothesis that the use of phonological codes is associated with good reading skills in deaf readers, though not well supported, still lingers in the literature. We investigated skilled and less-skilled adult deaf readers' processing of orthographic and phonological codes in parafoveal vision during reading by monitoring their eye movements and using the boundary paradigm. Orthographic preview benefits were found in early measures of reading for skilled hearing, skilled deaf, and less-skilled deaf readers, but only skilled hearing readers processed phonological codes in parafoveal vision. Crucially, skilled and less-skilled deaf readers showed a very similar pattern of preview benefits during reading. These results support the notion that reading difficulties in deaf adults are not linked to their failure to activate phonological codes during reading.

Synonyms provide semantic preview benefit in English

While orthographic and phonological preview benefits in reading are uncontroversial (see Schotter, Angele, & Rayner, 2012 for a review), researchers have debated the existence of semantic preview benefit with positive evidence in Chinese and German, but no support in English. Two experiments, using the gazecontingent boundary paradigm (Rayner, 1975), show that semantic preview benefit can be observed in English when the preview and target are synonyms (share the same or highly similar meaning, e.g., curlers-rollers). However, no semantic preview benefit was observed for semantic associates (e.g., curlers-styling). These different preview conditions represent different degrees to which the meaning of the sentence changes when the preview is replaced by the target. When this continuous variable (determined by a norming procedure) was used as the predictor in the analyses, there was a significant relationship between it and all reading time measures, suggesting that similarity in meaning between what is accessed parafoveally and what is processed foveally may be an important influence on the presence of semantic preview benefit. Why synonyms provide semantic preview benefit in reading English is discussed in relation to (1) previous failures to find semantic preview benefit in English and (2) the fact that semantic preview benefit is observed in other languages even for non-synonymous words. Semantic preview benefit is argued to depend on several factors-attentional resources, depth of orthography, and degree of similarity between preview and target.