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Sally Andrews - One of the best experts on this subject based on the ideXlab platform.
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The influence of number of syllables on word skipping during reading revisited
Psychonomic Bulletin & Review, 2019Co-Authors: Denis Drieghe, Aaron Veldre, Gemma Fitzsimmons, Jane Ashby, Sally AndrewsAbstract:Fitzsimmons and Drieghe ( Psychonomic Bulletin & Review, 18, 736–741, 2011 ) showed that a monosyllabic word was skipped more often than a disyllabic word during reading. This finding was interpreted as evidence that syllabic information was extracted from the Parafovea early enough to influence word skipping. In the present, large-scale replication of this study, in which we additionally measured the reading, vocabulary, and spelling abilities of the participants, the effect of number of syllables on word skipping was not significant. Moreover, a Bayesian analysis indicated strong evidence for the absence of the effect. The individual differences analyses replicate previous observations showing that spelling ability uniquely predicts word skipping (but not fixation times) because better spellers skip more often. The results indicate that high-quality lexical representations allow the system to reach an advanced stage in the word-recognition process of the Parafoveal word early enough to influence the decision of whether or not to skip the word, but this decision is not influenced by number of syllables.
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How does foveal processing difficulty affect Parafoveal processing during reading
Journal of Memory and Language, 2018Co-Authors: Aaron Veldre, Sally AndrewsAbstract:Abstract Models of eye movement control during reading assume that the difficulty of processing word n in a sentence modulates the depth of processing of the upcoming word/s (word n + 1) in the Parafovea. This foveal load hypothesis is widely accepted in the literature despite surprisingly few clear replications of the basic effect. We sought to establish whether observing a foveal load effect depends on the type of Parafoveal preview used in the boundary paradigm. Participants’ eye movements were recorded in two experiments as they read sentences in which a low- or high-frequency word n—a typical manipulation of foveal load—preceded a critical target word. Prior to the reader making a saccade to word n + 1, the Parafoveal preview was either identical to word n + 1; an orthographically similar word or nonword; or an unrelated word or nonword. The results revealed that the critical evidence for a foveal load effect—an interaction between word n frequency and word n + 1 preview—was limited to conditions in which the invalid preview baseline was an orthographically illegal nonword. The remaining conditions produced completely additive effects of the two factors. These findings raise questions about the mechanisms underlying the spillover of foveal processing difficulty to Parafoveal words. The implications for theories of reading are discussed.
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semantic preview benefit in english individual differences in the extraction and use of Parafoveal semantic information
Journal of Experimental Psychology: Learning Memory and Cognition, 2016Co-Authors: Aaron Veldre, Sally AndrewsAbstract:: 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
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Parafoveal preview benefit is modulated by the precision of skilled readers' lexical representations.
Journal of Experimental Psychology: Human Perception and Performance, 2014Co-Authors: Aaron Veldre, Sally AndrewsAbstract:: 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.
Keith Rayner - One of the best experts on this subject based on the ideXlab platform.
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rethinking Parafoveal processing in reading serial attention models can explain semantic preview benefit and n 2 preview effects
Visual Cognition, 2014Co-Authors: Elizabeth R Schotter, Keith RaynerAbstract:During reading, some information about the word to the right of fixation in the Parafovea is typically acquired prior to that word being fixated. Although some degree Parafoveal processing is uncontroversial, its precise nature and extent are unclear. For example, can it advance up to the level of semantic processing? Additionally, can it extend across more than two spatially adjacent words? Affirmative answers to either of these questions would seemingly be problematic for serial-attention models of eye-movement control in reading, which maintain that attention is allocated to only one word at a time (see Reichle, 2011). However, in this paper we report simulation results using one such model, E-Z Reader (Reichle, Pollatsek, Fisher, & Rayner, 1998), to examine the two preceding questions. These results suggest the existence of both semantic preview and N+2 preview effects, indicating that they are not incompatible with serial-attention models. We discuss the implications of these findings for models of e...
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Effects of Parafoveal word length and orthographic features on initial fixation landing positions in reading
Attention Perception & Psychophysics, 2012Co-Authors: Patrick Plummer, Keith RaynerAbstract:Previous research has demonstrated that readers use word length and word boundary information in targeting saccades into upcoming words while reading. Previous studies have also revealed that the initial landing positions for fixations on words are affected by Parafoveal processing. In the present study, we examined the effects of word length and orthographic legality on targeting saccades into Parafoveal words. Long (8–9 letters) and short (4–5 letters) target words, which were matched on lexical frequency and initial letter trigram, were paired and embedded into identical sentence frames. The gaze-contingent boundary paradigm (Rayner, 1975 ) was used to manipulate the Parafoveal information available to the reader before direct fixation on the target word. The Parafoveal preview was either identical to the target word or was a visually similar nonword. The nonword previews contained orthographically legal or orthographically illegal initial letters. The results showed that orthographic preprocessing of the word to the right of fixation affected eye movement targeting, regardless of word length. Additionally, the lexical status of an upcoming saccade target in the Parafovea generally did not influence preprocessing.
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Skilled Deaf Readers Have an Enhanced Perceptual Span in Reading
Psychological science, 2012Co-Authors: Nathalie N. Bélanger, Timothy J. Slattery, Rachel I. Mayberry, Keith RaynerAbstract:Recent evidence suggests that, compared with hearing people, deaf people have enhanced visual attention to simple stimuli viewed in the Parafovea and periphery. Although a large part of reading involves processing the fixated words in foveal vision, readers also utilize information in Parafoveal vision to preprocess upcoming words and decide where to look next. In the study reported here, we investigated whether auditory deprivation affects low-level visual processing during reading by comparing the perceptual span of deaf signers who were skilled and less-skilled readers with the perceptual span of skilled hearing readers. Compared with hearing readers, the two groups of deaf readers had a larger perceptual span than would be expected given their reading ability. These results provide the first evidence that deaf readers' enhanced attentional allocation to the Parafovea is used during complex cognitive tasks, such as reading.
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eye movements and the use of Parafoveal word length information in reading
Journal of Experimental Psychology: Human Perception and Performance, 2008Co-Authors: Barbara J Juhasz, Simon Paul Liversedge, Sarah J White, Keith RaynerAbstract:Eye movements were monitored in 4 experiments that explored the role of Parafoveal word length in reading. The experiments employed a type of compound word where the deletion of a letter results in 2 short words (e.g., backhand, back and). The boundary technique (K. Rayner, 1975) was employed to manipulate word length information in the Parafovea. Accuracy of the Parafoveal word length preview significantly affected landing positions and fixation durations. This disruption was larger for 2-word targets, but the results demonstrated that this interaction was not due to the morphological status of the target words. Manipulation of sentence context also demonstrated that Parafoveal word length information can be used in combination with sentence context to narrow down lexical candidates. The 4 experiments converge in demonstrating that an important role of Parafoveal word length information is to direct the eyes to the center of the Parafoveal word.
Aaron Veldre - One of the best experts on this subject based on the ideXlab platform.
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The influence of number of syllables on word skipping during reading revisited
Psychonomic Bulletin & Review, 2019Co-Authors: Denis Drieghe, Aaron Veldre, Gemma Fitzsimmons, Jane Ashby, Sally AndrewsAbstract:Fitzsimmons and Drieghe ( Psychonomic Bulletin & Review, 18, 736–741, 2011 ) showed that a monosyllabic word was skipped more often than a disyllabic word during reading. This finding was interpreted as evidence that syllabic information was extracted from the Parafovea early enough to influence word skipping. In the present, large-scale replication of this study, in which we additionally measured the reading, vocabulary, and spelling abilities of the participants, the effect of number of syllables on word skipping was not significant. Moreover, a Bayesian analysis indicated strong evidence for the absence of the effect. The individual differences analyses replicate previous observations showing that spelling ability uniquely predicts word skipping (but not fixation times) because better spellers skip more often. The results indicate that high-quality lexical representations allow the system to reach an advanced stage in the word-recognition process of the Parafoveal word early enough to influence the decision of whether or not to skip the word, but this decision is not influenced by number of syllables.
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How does foveal processing difficulty affect Parafoveal processing during reading
Journal of Memory and Language, 2018Co-Authors: Aaron Veldre, Sally AndrewsAbstract:Abstract Models of eye movement control during reading assume that the difficulty of processing word n in a sentence modulates the depth of processing of the upcoming word/s (word n + 1) in the Parafovea. This foveal load hypothesis is widely accepted in the literature despite surprisingly few clear replications of the basic effect. We sought to establish whether observing a foveal load effect depends on the type of Parafoveal preview used in the boundary paradigm. Participants’ eye movements were recorded in two experiments as they read sentences in which a low- or high-frequency word n—a typical manipulation of foveal load—preceded a critical target word. Prior to the reader making a saccade to word n + 1, the Parafoveal preview was either identical to word n + 1; an orthographically similar word or nonword; or an unrelated word or nonword. The results revealed that the critical evidence for a foveal load effect—an interaction between word n frequency and word n + 1 preview—was limited to conditions in which the invalid preview baseline was an orthographically illegal nonword. The remaining conditions produced completely additive effects of the two factors. These findings raise questions about the mechanisms underlying the spillover of foveal processing difficulty to Parafoveal words. The implications for theories of reading are discussed.
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semantic preview benefit in english individual differences in the extraction and use of Parafoveal semantic information
Journal of Experimental Psychology: Learning Memory and Cognition, 2016Co-Authors: Aaron Veldre, Sally AndrewsAbstract:: 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
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Parafoveal preview benefit is modulated by the precision of skilled readers' lexical representations.
Journal of Experimental Psychology: Human Perception and Performance, 2014Co-Authors: Aaron Veldre, Sally AndrewsAbstract:: 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.
Peter C. Gordon - One of the best experts on this subject based on the ideXlab platform.
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Word skipping during sentence reading: effects of lexicality on Parafoveal processing
Attention perception & psychophysics, 2013Co-Authors: Wonil Choi, Peter C. GordonAbstract:Two experiments examined how lexical status affects the targeting of saccades during reading by using the boundary technique to vary independently the content of a letter string when seen in Parafoveal preview and when directly fixated. Experiment 1 measured the skipping rate for a target word embedded in a sentence under three Parafoveal preview conditions: full preview (e.g., brain–brain), pseudohomophone preview (e.g., brane–brain), and orthographic nonword control preview (e.g., brant–brain); in the first condition, the preview string was always an English word, while in the second and third conditions, it was always a nonword. Experiment 2 investigated three conditions where the preview string was always a word: full preview (e.g., beach–beach), homophone preview (e.g., beech–beach), and orthographic control preview (e.g., bench–beach). None of the letter string manipulations used to create the preview conditions in the experiments disrupted sublexical orthographic or phonological patterns. In Experiment 1, higher skipping rates were observed for the full (lexical) preview condition, which consisted of a word, than for the nonword preview conditions (pseudohomophone and orthographic control). In contrast, Experiment 2 showed no difference in skipping rates across the three types of lexical preview conditions (full, homophone, and orthographic control), although preview type did influence reading times. This pattern indicates that skipping not only depends on the presence of disrupted sublexical patterns of orthography or phonology, but also is critically dependent on processes that are sensitive to the lexical status of letter strings in the Parafovea.
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Coordination of Word Recognition and Oculomotor Control During Reading: The Role of Implicit Lexical Decisions
Journal of Experimental Psychology: Human Perception and Performance, 2012Co-Authors: Wonil Choi, Peter C. GordonAbstract:Recognizing words so that their meanings can be retrieved is critical to successful reading comprehension. These lexical processes must be coordinated with other perceptual, motor, and attentive processes in order for eye movements during reading to be controlled efficiently. During reading the eyes alternate between fixations (periods when the eyes are nearly stationary) and saccades (rapid ballistic movements); for skilled readers saccades typically occur four to five times per second with most words receiving only a single first-pass fixation (Rayner, 1998). Oculomotor processes, which are constrained by differential acuity across the retina and by the nature of ocular motor control, are major determinants of eye movements during reading. The contribution of these processes can be seen in how physical characteristics of text, such as the length of words, influence the pattern of fixations and saccades. Language-based processes that relate to comprehension of the text also exert a strong influence on when – and occasionally where – the eyes move during reading. The contribution of these processes can be seen in how eye movements are influenced by non-physical aspects of the text such as word frequency or the predictability of a word in context. Very different explanations have been advanced for how oculomotor and language-based processes are coordinated. At one extreme it is argued that language-based effects on eye-movements lead to only slight modulation of a more basic oculomotor process that generates forward saccades of a standard length at a regular rhythm (McConkie, Kerr, Reddix, & Zola, 1988; O’Regan, 1990; Yang & McConkie, 2001). At the other extreme it is argued that, while oculomotor processes determine most characteristics of the targeting of forward saccades, word recognition determines when saccades are initiated and in some instances their targeting (Morrison, 1984; Pollatsek, Reichle & Rayner, 2006; Reichle, Pollatsek, Fisher, & Rayner, 1998). Other models take more intermediate positions (Engbert, Nuthmann, Richter, & Kliegl, 2005; Reichle, Rayner, & Pollatsek, 2003). The phenomenon of skipping, where a word is not directly fixated during the first pass of the eyes over the text, has been central to the evaluation of these alternative models. Word length has a very strong effect on skipping, with short words skipped more frequently than long words (Kerr, 1992; Vitu, O’Regan, Inhoff, & Topolski, 1995; for a review see Brysbaert, Drieghe, & Vitu, 2005). This effect can be readily understood as resulting from visual and motor processes. A short word to the right of the fixated word is seen more clearly than a long word because it is more likely to fit within the fovea. Further, having the eyes land on short words tends to require shorter saccades than having them land on long words, which increases the likelihood that short words will be skipped because motor error in saccade targeting takes the form of overshoot for short saccades and undershoot for long saccades (McConkie, Kerr, & Dyre, 1994; McConkie et al., 1988). Language-based factors also affect skipping, such that frequent and predictable words are more likely to be skipped than infrequent or unpredictable words (Ehrlich & Rayner, 1981; Rayner & Fisher, 1996; Rayner & Raney, 1996; Rayner & Well, 1996; Schilling, Rayner, & Chumbley, 1998; White, 2008). Skipping effects are interesting in part because they are the only case where language factors related to word recognition affect the targeting of forward saccades rather than just their timing (Drieghe, Rayner, & Pollatsek, 2005). As such, skipping has been an important arena for addressing the manner in which lexical processing is coordinated with processes of attention, vision and motor control during reading. Models of eye movement control that attribute only a small role to language-based processing relative to oculomotor processing account for language effects on skipping in a number of ways. For example, according to the Extended Optimal Viewing Position (EOVP) model, language-based skips are in essence an educated guess based on factors such as word length and very partial word identification (Brysbaert & Vitu, 1998). The main determinants of the decision to skip a word are the length of the word in the Parafovea and the experience the system has built up with how often a word of a certain length at a certain distance can be skipped without hindering overall text comprehension. Consequently that decision is made with very limited information about the identity of the skipped word. Models of eye-movement control that attribute a more substantial role to language-based (or cognitive) factors have gone through a number of iterations and refinements, but have retained a core set of mechanisms to account for language-based skipping as described by the EZ Reader model (Morrison, 1984; Pollatsek et al., 2006; Reichle et al., 1998). These models posit a serial-attention-shifting mechanism where words in the text are processed one at a time (though recognition of a word is achieved by matching the stimulus to multiple lexical and sublexical representations in parallel). Once the fixated word is recognized, attention shifts to processing Parafoveal information about the next word. Attention shifts prior to movement of the eyes because of limits on the rate at which saccades can be generated. In the majority of cases the oculomotor system then executes a planned saccade which has been targeted to the next word on the basis of a parallel process of visual analysis that locates word boundaries. The processing that occurs prior to fixation on that word provides a Parafoveal-preview benefit that facilitates recognition, a spillover effect that can be observed in first-pass reading times (Henderson & Ferreira, 1990; Kennison & Clifton, 1995; White, Rayner, & Liversedge, 2005). In a minority of cases, recognition of the word in the Parafovea occurs quickly enough that the planned saccade to that word can be cancelled and a new saccade can be programmed to a more distant word resulting in a skip of the word in the Parafovea. Thus, according to the EZ Reader model the ease of recognizing the current word affects both the amount of Parafoveal-preview benefit on the next word and, together with the ease of recognizing the next word, determines whether that next word is skipped. A strong association between ease of word recognition, Parafoveal preview benefit and skipping has been found for word frequency and predictability (e.g., Drieghe et al. 2005; Rayner & Fisher, 1996) though manipulations of the visual characteristics of text (Drieghe, 2008) and the phonological length of words (Fitzsimmons & Drieghe, 2011) have shown dissociations between these factors. An essential feature of the serial-attention-shifting models is that the same mechanisms are used for recognizing words in the fovea and Parafovea. In both cases the initiation of saccadic processes is linked to processing words to a level where the words are highly likely to be fully recognized soon (Pollatsek et al., 2006). Gordon, Plummer and Choi (in press) tested this model by using repetition to manipulate the ease of recognizing a target word while using the boundary technique (Rayner, 1975) to manipulate the information about that word available during Parafoveal preview. The boundary technique is a gaze-contingent method where the stimulus word changes when the eyes cross an invisible boundary on the screen, thereby allowing manipulation of the relationship between Parafoveal and foveal information about a word. In Gordon et al. the string in the Parafovea could either be the target word itself (e.g., the name Herman) or a nonword created by transposing two internal letters of the target word (e.g., Hreman). When used as primes in masked-priming studies or as preview strings in eye-movement studies, such transposed letter (TL) nonwords produce substantial facilitation in the subsequent processing of the target word as compared to substituted letter (SL) nonwords that have the same number of letter-in-position differences with the target word (Johnson, Perea, & Rayner, 2007; Perea & Lupker, 2003a, 2003b;). However, when TL nonwords are directly fixated they disrupt reading (causing longer first-pass reading times and greater likelihood of refixation) because they are not words (Rayner, White, Johnson, & Liversedge, 2006; White, Johnson, Liversedge, & Rayner, 2008). Gordon et al. found that facilitating lexical access through repetition increased skipping when the Parafoveal preview string was the target word itself, but that repetition had no effect on skipping when the Parafoveal preview string was a highly-similar TL nonword. This pattern supports serial-attention-shifting models, such as EZ Reader, by showing that the letter string in the Parafovea must be recognized as a word in order for lexical priming to increase skipping above the baseline rate that occurs due to oculomotor processes. Thus, it is not the case that contextual facilitation due to repetition priming constitutes a bias that combines with partial visual information from the periphery to increase skipping (see Engbert et al., 2005; Rayner, Slattery, Drieghe & Liversedge, 2011 for advocacy of such a mechanism in the case of word predictability). The Gordon et al. findings are consistent with models of eye-movement control during reading where the key link between language-based and oculomotor processes is an implicit lexical decision about whether the letter string in the Parafovea will be successfully recognized as a word.
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See before you jump: full recognition of Parafoveal words precedes skips during reading.
Journal of experimental psychology. Learning memory and cognition, 2012Co-Authors: Peter C. Gordon, Patrick Plummer, Wonil ChoiAbstract:Serial attention models of eye-movement control during reading were evaluated in an eye-tracking experiment that examined how lexical activation combines with visual information in the Parafovea to affect word skipping (where a word is not fixated during first-pass reading). Lexical activation was manipulated by repetition priming created through prime-target pairs embedded within a sentence. The boundary technique (Rayner, 1975) was used to determine whether the target word was fully available during Parafoveal preview or whether it was available with transposed letters (e.g., Herman changed to Hreman). With full Parafoveal preview, the target word was skipped more frequently when it matched the earlier prime word (i.e., was repeated) than when it did not match the earlier prime word (i.e., was new). With transposed-letter (TL) preview, repetition had no effect on skipping rates despite the great similarity of the TL preview string to the target word and substantial evidence that TL strings activate the words from which they are derived (Perea & Lupker, 2003). These results show that lexically based skipping is based on full recognition of the letter string in Parafoveal preview and does not involve using the contextual constraint to compensate for the reduced information available from the Parafovea. These results are consistent with models of eye-movement control during reading in which successive words in a text are processed 1 at a time (serially) and in which word recognition strongly influences eye movements.
Wojciech Hautz - One of the best experts on this subject based on the ideXlab platform.
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optical coherence tomography angiography of superficial retinal vessel density and foveal avascular zone in myopic children
PLOS ONE, 2019Co-Authors: Joanna Golebiewska, Karolina Bialagosek, Agnieszka Czeszyk, Wojciech HautzAbstract:PURPOSE: To assess the superficial retinal vessel density (SRVD) and foveal avascular zone (FAZ) in myopic children using optical coherence tomography angiography (OCTA). METHODS: 174 eyes of 89 subjects with myopia and 101 eyes of 54 age-matched, emmetropic volunteers (control group) were enrolled in this study. The mean age of the subjects and controls was 13.9 (SD ± 2.3) and 13.1 (SD ± 2.4), respectively. Myopia was defined as spherical equivalent <- 1.0 diopter. Emmetropic subjects were defined as having spherical equivalent from + 0.5 to - 0.5 diopter. The mean axial length (AL) in myopic patients was 24.58 mm (SD ± 1.22) and 22.88 mm (SD ± 0.65) in the controls. Every patient underwent a complete ophthalmological examination and OCTA, using AngioVue (Optovue). The FAZ area and superficial retinal vessel density, including whole SRVD, fovea SRVD and Parafovea SRVD, were analyzed. Foveal thickness (FT) and Parafoveal thickness (PFT) were also taken into consideration. RESULTS: Whole SRVD, Parafovea SRVD and PFT were significantly higher in controls than in the myopic subjects (p < 0.001, p = 0.007, p < 0.01, respectively). The FAZ area was significantly larger in the myopic group compared to the controls (p = 0.010). Fovea SRVD and FT did not differ significantly between the groups (p = 0.740, p = 0.795 respectively). In overall subjects we found significant correlation between axial length and all the investigative parameters: age, FAZ area, whole SRVD, Parafovea SRVD, fovea SRVD, PFT, FT (p < 0.001, p = 0.014, p = 0.008, p < 0.005, p = 0.014, p = 0.010, p = 0.024, respectively). Analyzing only myopic group we confirmed that AL was significantly correlated with age, whole SRVD and Parafovea SRVD (p < 0.001, p = 0.014, p = 0.009, respectively). Similarly, in this group the spherical equivalent also correlated with age, whole SRVD and Parafovea SRVD (p < 0.001, p = 0.007, p = 0.005, respectively). Such correlations were not confirmed in the non-myopic group. CONCLUSIONS: Our results suggest that superficial retinal vessel density is decreased and FAZ area is enlarged in the entire group of the myopic children compared to emmetropic subjects. Longitudinal observation of these young patients is needed to determine the relevance of the microvascular alterations in future.
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Optical coherence tomography angiography vessel density in children with type 1 diabetes.
PloS one, 2017Co-Authors: Joanna Gołębiewska, Andrzej Olechowski, Marta Wysocka-mincewicz, Dominik Odrobina, Marta Baszyńska-wilk, Artur Groszek, Mieczysław Szalecki, Wojciech HautzAbstract:Purpose To assess the optical coherence tomography angiography (OCTA) retinal vessel density and foveal avascular zone (FAZ) in children with type 1 diabetes (T1D) and compare potential pathologic early changes in this population to healthy age-matched controls. Methods This study included 130 pubescent children: 94 with T1D (188 eyes) and 36 of their age-matched control group (60 eyes). OCTA was performed using AngioVue (Avanti, Optivue). FAZ area (mm2) in superficial plexus, whole superficial capillary vessel density (wsVD), fovea superficial vessel density (fsVD), Parafovea superficial vessel density (psVD), whole deep vessel density (wdVD), fovea deep vessel density (fdVD), Parafovea deep vessel density (pdVD), foveal thickness (FT) (μm) and Parafoveal thickness (PFT) (μm) were taken into analysis. Among the studied patients with T1D there were assessed codependences regarding the investigated foveal and Parafoveal parameters and selected potential predictors, i.e. patient’s age (years), diabetes duration time (years), age of onset of the disease (years), mean level of glycated hemoglobin (HbA1C) (%), and concentration of serum creatinine (mg/dL). Results None of the abovementioned OCT and OCTA parameters was statistically significantly different between the groups. The patient’s age statistically significantly did not influent any of the OCT and OCTA parameters. Yet an elevated level of HbA1C tended to reduce the Parafovea superficial vessel density (p = 0.039), and Parafoveal thickness (p = 0.003) and an increased serum creatinine level correlated with the decreased whole deep vessel density (p < 0.001). The Parafovea deep vessel density in the diabetic patients decreased when the serum creatinine level (p = 0.008), age of onset of the disease (p = 0.028), and diabetes duration time (p = 0.014) rose. Conclusions Vessel density, both in superficial and deep plexuses, and FAZ area are normal in pubescent children with T1D comparing to healthy subjects. An elevated level of HbA1C correlated with reduced psVD and PFT. Longitudinal observation of these young patients is needed to determine if any of these OCTA measurements are predictive of future DR severity.
