I can read it in your eyes: what eye movements tell us about visuo-attentional processes in developmental dyslexia

Processing order in short-term memory is spatially biased in children

When processing serial information, adults tend to map elements of a sequence onto a mental horizontal line, following the direction of their reading and writing system. For example, in a Western population, the beginning of a series is associated with the left-hand side of the mental line, while its end is preferentially associated with the right. To complete the few studies that have investigated the cultural vs. innate determinants of such a spatial bias, the current study used a rotation task of unlabeled serial information. Experiment 1 measured the presence of a left-oriented bias in children from toddlers to grade 5 (aged 2 to 12 years old) and in adults. Results only showed a bias in adults. Experiment 2 was designed to avoid potential confounds identified in Experiment 1, and Experiment 3 provided more explicit information to participants, but the results still did not show a clear left-oriented bias in children. By controlling the mental rotation of our material in Experiment 4, we finally observed a global left-to-right bias across age groups, in particular between the 2nd grade (7 years old) and the 4th grade (9 years old), and in adults. Overall, this study shows that spatial-ordinal associations observed in adults can also be observed in children as early as primary school. In addition, a weaker bias was observed in younger children, which suggests that the effect could begin to emerge in preschool (4 years old) before being reinforced later with expertise in literacy.

The use of eye tracking in supporting individuals with dyslexia: a review

Dyslexia is defined as a specific learning disorder that impairs a person's ability to read fluently and accurately. A growing number of assistive technologies have been used to support individuals with dyslexia. Eye-tracking technology is one such technology, and it is gaining increasing attention from the research community due to its potential to be a valuable support tool for identifying underlying neural differences in language processing among this population. While the technology has seen significant advancements in recent years, researchers, particularly in psychology and special education, might face difficulties utilizing eye-tracking technology in their dyslexia research. The present study aims to provide a comprehensive overview of how eye tracking is employed in this field. By analysing 71 papers, we investigated the range of dyslexia-related aspects that were addressed by eye-tracking technology, how the technology was used, and the connections between eye-tracking measurements and reading in studies including individuals with dyslexia. This review article reveals that researchers have long recognized the potential of eye tracking in dyslexia research, as evidenced by the consistent focus on this technology in relevant studies throughout the years. Our paper also indicates the value of eye-tracking technology in exploring a wide range of dyslexia-related aspects. These include reading behaviours and information searching, the impact of materials on reading performance, detection, intervention, and the evaluation of intervention outcomes. Furthermore, by exploring both the achievements and shortcomings, the paper offers a valuable roadmap for future research specifically focused on supporting individuals with dyslexia.

Atypical oscillatory and aperiodic signatures of visual sampling in developmental dyslexia

Temporal processing deficits in Developmental Dyslexia (DD) have been documented extensively at the behavioral level, leading to the formulation of neural theories positing that such anomalies in parsing multisensory input rely on aberrant synchronization of neural oscillations or to an excessive level of neural noise. Despite reading being primarily supported by visual functions, experimental evidence supporting these theories remains scarce. Here, we tested 26 adults with DD (9 females) and 31 neurotypical controls (16 females) with a temporal segregation/integration task that required participants to either integrate or segregate two rapidly presented displays while their EEG activity was recorded. We confirmed a temporal sampling deficit in DD, which specifically affected the rapid segregation of visual input. While the ongoing alpha frequency and the excitation/inhibition (E/I) ratio (i.e., an index of neural noise quantified by the aperiodic exponent) were differently modulated based on task demands in typical readers, DD participants exhibited an impairment in alpha speed modulation and an altered E/I ratio that affected their rapid visual sampling. Nonetheless, an association between visual temporal sampling accuracy and both alpha frequency and the E/I ratio measured at rest were evident in the DD group, further confirming an anomalous interplay between alpha synchronization, the E/I ratio and active visual sampling. These results provide evidence that both trait- and state-like differences in alpha-band synchronization and neural noise levels coexist in the dyslexic brain and are synergistically responsible for cascade effects on visual sampling and reading.

Perceptual-Motor Abilities and Reversal Frequency of Letters and Numbers in Children Diagnosed with Poor Reading Skills

PURPOSE

This paper investigated the visual-perceptual and visual-motor skills and the reversal frequency of letters and numbers that mirror one another in one hundred children aged 6-13 years diagnosed with poor reading skills.

METHODS

TVPS-4th, VMI-6th, and RFT were performed. Age and sex analysis was carried out. The impact of the eye movement patterns in the perceptual-motor skills and laterality-directionality concepts was also estimated to determine the relationship among tests to predict future results.

RESULTS

Most children scored between average and 3 stds below average on the motor VMI-6th test, while half of the participants scored between average and 2 stds below average on TVPS-4th. In the RFT, the majority scored between average and 1.5 stds below average. Participants scored higher on the spatial relationship subtest of the TVPS-4th and lower in the VMI-6th test (p<0.001). Statistically significant differences were found between the youngest and oldest participants on the TVPS-4th overall performance, as well as VD, FC and VFG skills (p<0.05). A strong relationship was found between the TVPS-4th and VMI-6th, (p<0.001). RFT results were different among all groups (p<0.05). The RFT was better related to the VMI-6th than TVPS-4th; however, it was statistically insignificant. The horizontal component of the DEM test was the best predictor for the TVPS-4th and ratio for the RFT, without attaining statistical significance. No sex differences were found.

CONCLUSIONS

Results showed that children with poor reading skills exhibit perceptual-motor and reversal frequency difficulties, which are independent of the oculomotor performance. Considering that visual and motor processing are essential elements of the reading and writing process, their evaluation and treatment should be included as part of the multidisciplinary approach for children with poor reading skills. This would boost the general outcome and contribute to their academic achievement.

The perceptual span in dyslexic reading and visual search

Many studies have attempted to identify the root cause of dyslexia. Different theories of dyslexia have proposed either a phonological, attentional, or visual deficit. While research has used eye-tracking to study dyslexia, only two previous studies have used the moving-window paradigm to explore the perceptual span in dyslexic reading, and none have done so in visual search. The present study analysed the perceptual span using both reading and visual search tasks to identify language-independent attentional impairments in dyslexics. We found equivocal evidence that the perceptual span was impaired in dyslexic reading and no evidence of impairment in visual search. However, dyslexic participants did show deficits in the visual search task, with lower search accuracy and shorter saccades compared with controls. These results lend support for a visual, rather than attentional or phonological, account of dyslexia.

Oculomotor Patterns in Children with Poor Reading Abilities Measured Using the Development Eye Movement Test

Objectives: The main purpose of this work was to clinically assess the oculomotricity of one hundred Mexican children with poor reading skills but without any specific learning disorder. Methods: The D.E.M. psychometric test was used. Sex and age analyses of the ratio, type, horizontal and vertical performance, and errors were carried out. Results: Our data suggest that 84% of poor readers exhibit oculomotor difficulties. Sex did not significantly influence the results (p > 0.05), whereas age was associated with the horizontal (p = 0.04) and vertical (p = 0.29) performance, as well as the number of errors (p = 0.001). Omissions were the most prevalent error type. Conclusions: This research gives insights into the role of oculomotricity in children with poor reading skills. Our results suggest that oculomotor performance should be included in the evaluation protocol to assess poor readers to identify any influence of the visual system.

The Role of Visual Factors in Dyslexia

What are the causes of dyslexia? Decades of research reflect a determined search for a single cause where a common assumption is that dyslexia is a consequence of problems with converting phonological information into lexical codes. But reading is a highly complex activity requiring many well-functioning mechanisms, and several different visual problems have been documented in dyslexic readers. We critically review evidence from various sources for the role of visual factors in dyslexia, from magnocellular dysfunction through accounts based on abnormal eye movements and attentional processing, to recent proposals that problems with high-level vision contribute to dyslexia. We believe that the role of visual problems in dyslexia has been underestimated in the literature, to the detriment of the understanding and treatment of the disorder. We propose that rather than focusing on a single core cause, the role of visual factors in dyslexia fits well with risk and resilience models that assume that several variables interact throughout prenatal and postnatal development to either promote or hinder efficient reading.

Reading numbers is harder than reading words: An eye-tracking study

We recorded the eye movements of adults reading aloud short (four digit) and long (eight to 11 digit) Arabic numerals compared to matched-in-length words and pseudowords. We presented each item in isolation, at the center of the screen. Participants read each item aloud at their pace, and then pressed the spacebar to display the next item. Reading accuracy was 99 %. Results showed that adults make 2.5 times more fixations when reading short numerals compared to short words, and up to 7 times more fixations when reading long numerals with respect to long words. Similarly, adults make 3 times more saccades when reading short numerals compared to short words, and up to 9 times more saccades when reading long numerals with respect to long words. Fixation duration and saccade amplitude stay almost the same when reading short numerals with respect to short words. However, fixation duration increases by ∼50 ms when reading long numerals (∼300 ms) with respect to long words (∼250 ms), and saccade amplitude decreases up to 0.83 characters when reading long numerals with respect to long words. The pattern of findings for long numerals-more and shorter saccades as well as more and longer fixations-shows the extent to which reading long Arabic numerals is a cognitively costly task. Within the phonographic writing system, this pattern of eye movements stands for the use of the sublexical print-to-sound correspondence rules. The data highlight that reading large numerals is an unautomatized activity and that Arabic numerals must be converted into their oral form by a step-by-step process even by expert readers.

Eye-Tracker Study of the Developmental Eye Movement Test in Young People without Binocular Dysfunctions

Background: The purpose of this study was to evaluate ocular motility in normal young adults when performing the Developmental Eye Movement (DEM) test using an infrared eye-tracker in a sample of young subjects without visual dysfunctions. Methods: An optometric evaluation was carried out on 52 participants with a mean age of 21.00 ± 3.22 years to verify they did not have any binocular dysfunction, by completing a computerized version of the DEM test while their eye movements were recorded with an eye-tracker. A custom-written software was developed to analyse some specific parameters of ocular motility while performing each subtest (Test A, Test B and Test C) of the complete DEM test. Results: The mean duration of the fixations was shorter in Test C (243.56 ± 46.18 s) than in Test A (493.52 ± 171.41 s) and Test B (484.20 ± 156.59 s). The mean adjusted horizontal (AdjHT: 35.24 ± 6.68 s) and vertical (VT: 33.58 ± 5.56 s) times were at the 45th and at the 40th percentile, respectively. In Test C, there was a high positive significant correlation between the saccadic speed (cc: 0.77; p < 0.001) and the saccadic length (cc: 0.74; p < 0.001) of both eyes. Conclusions: The eye-tracker is an objective method to evaluate the DEM test in subjects without binocular dysfunctions, measuring and quantifying ocular motility parameters that are impossible with the traditional subjective method. The eye movements of both eyes are conjugated in each subject, having saccades of the same length and speed.

Eye-Movements in a Text Reading Task: A Comparison of Preterm Children, Children with Dyslexia and Typical Readers

Preterm birth is associated with weaknesses in reading skills that are usually less severe than those of children with dyslexia. To understand the characteristics of reading processes in preterm children, we adopted a cross-population and multi-modal approach comparing eye movements in reading tasks among three groups: children with preterm birth, children with a diagnosis of dyslexia, and children with typical development. The study involved 78 participants (10.5 years). Eye movements (number and duration of fixations, amplitude and number of saccades, number of regressions) were recorded during the silent reading of two texts; cognitive and reading standardized tasks were also administered. Children with dyslexia had more fixations and more frequent and smaller saccades compared to the preterm group and children with typical development. They also showed more regressions compared to the control group. Preterm children showed shorter fixations compared to the other groups. Cognitive and reading standardized tasks confirmed severe delays in reading in children with dyslexia and some weaknesses in text reading speed and comprehension in preterm children. These results are discussed with reference to candidate mechanisms that underlie reading processes in preterm children and considering possible implications for research.

Reading Specific Small Saccades Predict Individual Phonemic Awareness and Reading Speed

Small fixational eye-movements are a fundamental aspect of vision and thought to reflect fine shifts in covert attention during active viewing. While the perceptual benefits of these small eye movements have been demonstrated during a wide range of experimental tasks including during free viewing, their function during reading remains surprisingly unclear. Previous research demonstrated that readers with increased microsaccade rates displayed longer reading speeds. To what extent increased fixational eye movements are, however, specific to reading and might be indicative of reading skill deficits remains, however, unknown. To address this topic, we compared the eye movement scan paths of 13 neurotypical individuals and 13 subjects diagnosed with developmental dyslexia during short story reading and free viewing of natural scenes. We found that during reading only, dyslexics tended to display small eye movements more frequently compared to neurotypicals, though this effect was not significant at the population level, as it could also occur in slow readers not diagnosed as dyslexics. In line with previous research, neurotypical readers had twice as many regressive compared to progressive microsaccades, which did not occur during free viewing. In contrast, dyslexics showed similar amounts of regressive and progressive small fixational eye movements during both reading and free viewing. We also found that participants with smaller fixational saccades from both neurotypical and dyslexic samples displayed reduced reading speeds and lower scores during independent tests of reading skill. Slower readers also displayed greater variability in the landing points and temporal occurrence of their fixational saccades. Both the rate and spatio-temporal variability of fixational saccades were associated with lower phonemic awareness scores. As none of the observed differences between dyslexics and neurotypical readers occurred during control experiments with free viewing, the reported effects appear to be directly related to reading. In summary, our results highlight the predictive value of small saccades for reading skill, but not necessarily for developmental dyslexia.

Atypical viewing position effect in developmental dyslexia: A behavioural and modelling investigation

The probability of recognizing a word depends on the position of fixation during processing. In typical readers, the resulting word-recognition curves are asymmetrical, showing a left-of-centre optimal viewing position (OVP). First, we report behavioural results from dyslexic participants who show atypical word-recognition curves characterized by the OVP being right of centre with recognition probability being higher on the rightmost than on the leftmost letters. Second, we used BRAID, a Bayesian model of word recognition that implements gaze position, an acuity gradient, lateral interference and a visual attention component, to examine how variations in the deployment of visual attention would affect the OVP curves. We show that the atypical dyslexic curves are well simulated assuming a narrow distribution of visual attention and a shifting of visual attention towards the left visual field. These behavioural and modelling findings are discussed in light of current theories of visual attention deficits in developmental dyslexia.

Eye movement patterns and reading ability in children

PURPOSE

Eye movements are integral to the reading process. This study characterised the eye movement patterns of children differentiated by their reading ability, while completing a saccadic eye movement test with irregular target spacing (Development Eye Movement (DEM) test) using a novel eye movement classification algorithm.

METHODS

Participants included 196 Grade 2 Australian schoolchildren (mean age: 7.9 ± 0.3 years) who completed a computerised version of the DEM test, while their eye movements were recorded (Tobii TX300 eye-tracker). Children also completed a standardised reading comprehension test, which categorised them into below average and average or above reading ability groups. A novel eye movement classification algorithm was developed that considered the vertical and horizontal eye movements of each child.

RESULTS

Compared to children with average or above reading ability, the below average reading group displayed poor vertical eye movement control, demonstrated by a significantly greater proportion of interline eye movements (vertical eye movements away from the current line) (p < 0.001). Differences in horizontal eye movements were also observed, with below average readers demonstrating a smaller proportion of expected forward saccades (p < 0.001) (within-line forward saccades with horizontal amplitude between the minimum and maximum horizontal spacing between digits), while this group also displayed longer fixation durations (p = 0.001). The below average reading group demonstrated significantly poorer results on all standard DEM metrics than the average or above reading ability group: horizontal subtest time (p < 0.001), vertical subtest time (p = 0.004) and ratio (p = 0.004).

CONCLUSIONS

Children exhibiting below average reading ability were poorer at maintaining control of vertical (interline), as well as horizontal, eye movements compared to children with average or above reading ability. Future studies should explore the mechanisms underlying these differences, particularly in vertical eye movements, given that reading paragraphs (involving multiple lines of text) requires accurate eye movements in both the vertical and horizontal direction.

"Same, same but different": The optimal viewing position effect in developmental dyslexia, developmental coordination disorder and comorbid disorders

The optimal viewing position (OVP) effect indicates that words are identified most quickly when the eyes fixate near the word centre in alphabetic languages. In two studies, we tested OVP in typically developing readers and children with developmental dyslexia (DD), developmental coordination disorder (DCD) and with both disorders (DD + DCD), using a variable-viewing-position technique. Study 1 showed that typically developing readers had developed highly automatized procedures of left-to-right attentional scanning resulting in an inverted J-shape VP curve comparable to what is observed in adult readers and that dyslexics showed non-prototypical one. In Study 2, we observed more typical procedures of left-to-right attentional scanning in children with DCD, isolated or comorbid, compared to DD. Moreover, given the absence of significant group differences between children with DD + DCD and children with isolated DD or DCD, our results reinforce the idea that the comorbid condition does not add to the severity of OVP anomalies. We then concluded that OVP atypicalities are specific to children with DD. Finally, we discussed the usefulness of the OVP effect as a clinical tool to identify possible OVP atypicalities that could be specific of some neurodevelopmental disorders (i.e., DD, DCD or DCD + DD).

Comprehension and Eye Movements in the Processing of Subject- and Object-Relative Clauses: Evidence from Dyslexia and Individual Differences

In this study, we examined eye movements and comprehension in sentences containing a relative clause. To date, few studies have focused on syntactic processing in dyslexia and so one goal of the study is to contribute to this gap in the experimental literature. A second goal is to contribute to theoretical psycholinguistic debate concerning the cause and the location of the processing difficulty associated with object-relative clauses. We compared dyslexic readers (n = 50) to a group of non-dyslexic controls (n = 50). We also assessed two key individual differences variables (working memory and verbal intelligence), which have been theorised to impact reading times and comprehension of subject- and object-relative clauses. The results showed that dyslexics and controls had similar comprehension accuracy. However, reading times showed participants with dyslexia spent significantly longer reading the sentences compared to controls (i.e., a main effect of dyslexia). In general, sentence type did not interact with dyslexia status. With respect to individual differences and the theoretical debate, we found that processing difficulty between the subject and object relatives was no longer significant when individual differences in working memory were controlled. Thus, our findings support theories, which assume that working memory demands are responsible for the processing difficulty incurred by (1) individuals with dyslexia and (2) object-relative clauses as compared to subject relative clauses.

Investigating Issues and Needs of Dyslexic Students at University: Proof of Concept of an Artificial Intelligence and Virtual Reality-Based Supporting Platform and Preliminary Results

Specific learning disorders affect a significant portion of the population. A total of 80% of its instances are dyslexia, which causes significant difficulties in learning skills related to reading, memorizing and the exposition of concepts. Whereas great efforts have been made to diagnose dyslexia and to mitigate its effects at primary and secondary school, little has been done at the university level. This has resulted in a sensibly high rate of abandonment or even of failures to enroll. The VRAIlexia project was created to face this problem by creating and popularizing an innovative method of teaching that is inclusive for dyslexic students. The core of the project is BESPECIAL, a software platform based on artificial intelligence and virtual reality that is capable of understanding the main issues experienced by dyslexic students and to provide them with ad hoc digital support methodologies in order to ease the difficulties they face in their academic studies. The aim of this paper is to present the conceptual design of BESPECIAL, highlighting the role of each module that composes it and the potential of the whole platform to fulfil the aims of VRAIlexia. Preliminary results obtained from a sample of about 700 dyslexic students are also reported, which clearly show the main issues and needs that dyslexic students experience and these will be used as guidelines for the final implementation of BESPECIAL.

Predicting future poor readers from pre-reading visual skills: A longitudinal study

Reading is essential for learning, from literature to physics, from paper to screens on e-readers and smart phones. Even if it is well known that learning to read implies good language skills, children also need to develop good oculomotor and visual-perception skills. Thereby, any deficits in visual processing may affect learning. The possible impact of visual deficits is rarely considered, especially with regard to eye movements and visual perception. Hence, these deficits are usually discovered much later or remain undiagnosed. The present study aimed at assessing the usefulness of visual processing related measures in the early detection of reading difficulties. Visual skill differences that are apparent early in kindergarten might provide predictive insights into risk for learning difficulties at school entry. We used a prospective, longitudinal approach where visual processes (assessed with the Developmental Eye Movement (DEM) test) were measured in 51 preschoolers, and the impact of these processes on future reading development was explored one year later, in Grade 1. Results showed that (1) 31% of our sample of preschoolers showed visual processing impairments (without any clinical complaints) and (2) reading accuracy and speed in first graders were significantly correlated with visual skills assessed in kindergarten, thus confirming the significant role of oculomotor and visual-perception processes in the acquisition of reading skills. These suggests the potential for these measures to be used clinically for identifying children at risk for low academic achievement, enabling appropriate targeting of early interventions.

Effect of comorbid developmental dyslexia on oculomotor behavior in children with developmental coordination disorder: A study with the Developmental Eye Movement test

Studies have suggested a dysfunction in oculomotor skills in children with developmental coordination disorder (DCD). It has been proposed that the Developmental Eye Movement (DEM) test is useful in testing the dyslexics' (DD) oculomotor behavior during reading, in a simple and indirect manner. The present study aimed at exploring the oculomotor behavior in children with DCD as assessed with the DEM test. We thus compared children with DCD to children with DD and to children with both DCD and DD in order to investigate the specificity of the oculomotor difficulties, as measured by the DEM test. Results showed that 1) children with DCD presented mild atypical performance at the DEM test (error z-score only), 2) children with DD presented particularly poor performance at the DEM test, and 3) the co-morbid condition (DCD + DD) did not add to the severity of atypical performance at the DEM test. In sum, children with DCD were the less affected according to the DEM test, and children with DD (isolated or comorbid) presented the most atypical performance. Results at the DEM test did not allow to highlight clear oculomotor atypicalities in DCD. We thus concluded that more research using eye-tracking techniques is needed to explore the nature of oculomotor atypicalities in DCD children, to distinguish DD and DCD oculomotor behavior, and to understand the profile of children with dual diagnosis.

Exploring the Moderation Effect of Educational Stage on Visual Magnocellular Functioning Linked to Reading: A Study in French Primary School Children

Many studies have investigated the visual magnocellular system functioning in dyslexia. However, very little is known on the relationship between the visual magnocellular system functioning and reading abilities in typical developing readers. In this study, we aimed at studying this relationship and more specifically the moderation effect of educational stage on this link. We thus tested 82 French typical developing readers (40 beginning readers-Grade 1 and 42 advanced readers-Grade 5) with reading tests and a coherent dot motion task measuring the visual magnocellular functioning. Results indicate positive correlations between visual magnocellular functioning and reading for beginning readers but not for advanced readers. Moreover, moderation analyses confirm that reading proficiency moderates the relationship between magnocellular system functioning and reading outcomes. We concluded that the relationship between visual magnocellular pathway functioning and reading abilities in typical developing readers could depend on reading proficiency.

Atypical Visual Scan Path Affects Remembering in ADHD

OBJECTIVE

Several studies agree on the link between attention and eye movements during reading. It has been well established that attention and working memory (WM) interact. A question that could be addressed to better understand these relationships is: to what extent can an attention deficit affect eye movements and, consequently, remembering a word? The main aims of the present study were (1) to compare visual patterns of word stimuli between children with Attention Deficit Hyperactivity Disorder (ADHD) and typically developing (TD) children, during a visual task on word stimuli; (2) to examine the WM accuracy of the word stimuli; and (3) to compare the dynamic of visual scan path in both groups.

METHOD

A total of 49 children with ADHD, age and sex matched with 32 TD children, were recruited. We used eye-tracking technology in which the Word Memory Test was implemented. To highlight the scan path of participants, two measures were used: the ordered direction of reading and the entropy index.

RESULTS

ADHD groups showed a poorer WM than TD group. They did not follow a typical scan path across the words compared with TD children, but their visual scanning was discontinuous, uncoordinated, and chaotic. ADHD groups showed an index of entropy among the four categories of saccades higher than TD group.

CONCLUSIONS

The findings were discussed in light of two directions: the relationship between atypical visual scan path and WM and the training implications related to the necessity of redirecting the dynamic of visual scan path in ADHD to improve WM.

Eye Movements During RAN as an Operationalization of the RAN-Reading "Microcosm"

Rapid Automatized Naming (RAN) is a strong predictor of reading aloud, though there is little agreement on what underpins RAN or how it relates to reading. Some theorize phonological skills, while others suggest that RAN reflects the “microcosm” of cognitive and attentional processes also required for reading, with more recent research using eye movements in an attempt to study this relationship. In the current study, we aimed to extend previous investigations to identify whether the temporal patterns of eye movements predict RAN and can, therefore, be established as a method to study the cognitive processes underlying RAN that could then be utilized to elucidate the relationship of RAN to reading. A Gazepoint eye tracker was used to record the eye movements of 93 learner readers aged 5–8 years (M age = 7.00) while performing a custom computerized alphabetic RAN task. Text reading accuracy, comprehension and rate; nonverbal intelligence; and phonological awareness abilities were also assessed. Regression analyses showed that, independently of phonological awareness, eye movements [Fixation Count (FC) and Fixation Duration (FD)] measured during RAN tasks were highly reflective of children’s rapid naming performance (92.8%). Both mean FC and mean FD during RAN tasks also predicted text reading accuracy (36.3%), comprehension (31.6%), and rate (36.2%) scores, and in predicting these text reading skills there was a high level of shared variance with RAN performance. In a sub-sample of participants, longer average FDs and counts independently discriminated children with reading difficulties (n = 18; aged 7–9) from neurotypical children matched for age (n = 18), but not from younger neurotypical children matched for reading level (n = 18; aged 5–6). Together, these results suggest that the analysis of eye movements recorded during RAN allows for the operationalization of many of the spatially and temporally-bound cognitive and attentional processes that underpin the RAN, and a step towards elucidating its relationship to reading.

Pre-schoolers' visual perception and attention networks influencing naming speed: An individual difference perspective

Naming speed is considered to be one of the essential components used to predict reading capacity in school. The current study examined how visual perception and attention networks influence naming speed, and analyzed the relationship between visual perception and attention networks. The total number of participants was 163 Thai preschool children between the ages of five and seven years selected through multistage random sampling. Visual perception, attention networks, and naming speed were assessed using the Developmental Test of Visual Perception 3 (DTVP-3), Attention Network Task (ANT), and Rapid Automatized Naming (RAN), respectively. Structural equation modeling was used to test naming speed hypotheses. The hypothesis of a causal model was supported by the evidence generated by this study. A direct positive association between both visual perception and attention networks to naming speed was observed. Compared with attention networks, visual perception had a higher significant effect on naming speed performance. Consequently, children who have higher visual perception are more likely to demonstrate a better naming speed performance. These results indicate that visual perception is strongly urged to naming speed, as doing so can help predict children's reading readiness before they start learning to read.

Modality and redundancy effects, and their relation to executive functioning in children with dyslexia

Children with dyslexia are often provided with audio-support to compensate for their reading problems, but this may intervene with their learning. The aim of the study was to examine modality and redundancy effects in 21 children with dyslexia, compared to 21 typically developing peers (5^th grade), on study outcome (retention and transfer knowledge) and study time in user-paced learning environments and the role of their executive functions (verbal and visual working memory, inhibition, and cognitive flexibility) on these effects. Results showed no effects on retention knowledge. Regarding transfer knowledge, a modality effect in children with dyslexia was found, and a reversed redundancy effect in typically developing children. For transfer knowledge, written text with pictures supported knowledge gain in typically developing children, but not in children with dyslexia who benefited more from auditory-presented information with pictures. Study time showed modality and reversed redundancy effects in both groups. In all children, studying in a written text with pictures condition took longer than with audio replacing the text or being added to it. Results also showed that executive functions were related to learning, but they did not differ between the groups, nor did they impact the found modality and redundancy effects. The present research thus shows that, irrespectively of children's executive functions, adding audio-support for all children, can potentially lead to more efficient learning.

Effects of Reading Proficiency and of Base and Whole-Word Frequency on Reading Noun- and Verb-Derived Words: An Eye-Tracking Study in Italian Primary School Children

The aim of this study is to assess the role of readers' proficiency and of the base-word distributional properties on eye-movement behavior. Sixty-two typically developing children, attending 3rd, 4th, and 5th grade, were asked to read derived words in a sentence context. Target words were nouns derived from noun bases (e.g., umorista, 'humorist'), which in Italian are shared by few derived words, and nouns derived from verb bases (e.g., punizione, 'punishment'), which are shared by about 50 different inflected forms and several derived words. Data shows that base and word frequency affected first-fixation duration for nouns derived from noun bases, but in an opposite way: base frequency had a facilitative effect on first fixation, whereas word frequency exerted an inhibitory effect. These results were interpreted as a competition between early accessed base words (e.g., camino, chimney) and target words (e.g., caminetto, fireplace). For nouns derived from verb bases, an inhibitory base frequency effect but no word frequency effect was observed. These results suggest that syntactic context, calling for a noun in the target position, lead to an inhibitory effect when a verb base was detected, and made it difficult for readers to access the corresponding base+suffix combination (whole word) in the very early processing phases. Gaze duration was mainly affected by word frequency and length: for nouns derived from noun bases, this interaction was modulated by proficiency, as length effect was stronger for less proficient readers, while they were processing low-frequency words. For nouns derived from verb bases, though, all children, irrespective of their reading ability, showed sensitivity to the interaction within frequency of base+suffix combination (word frequency) and target length. Results of this study are consistent with those of other Italian studies that contrasted noun and verb processing, and confirm that distributional properties of morphemic constituents have a significant impact on the strategies used for processing morphologically complex words.

Review of EEG-based pattern classification frameworks for dyslexia

Dyslexia is a disability that causes difficulties in reading and writing despite average intelligence. This hidden disability often goes undetected since dyslexics are normal and healthy in every other way. Electroencephalography (EEG) is one of the upcoming methods being researched for identifying unique brain activation patterns in dyslexics. The aims of this paper are to examine pros and cons of existing EEG-based pattern classification frameworks for dyslexia and recommend optimisations through the findings to assist future research. A critical analysis of the literature is conducted focusing on each framework’s (1) data collection, (2) pre-processing, (3) analysis and (4) classification methods. A wide range of inputs as well as classification approaches has been experimented for the improvement in EEG-based pattern classification frameworks. It was uncovered that incorporating reading- and writing-related tasks to experiments used in data collection may help improve these frameworks instead of using only simple tasks, and those unwanted artefacts caused by body movements in the EEG signals during reading and writing activities could be minimised using artefact subspace reconstruction. Further, support vector machine is identified as a promising classifier to be used in EEG-based pattern classification frameworks for dyslexia.

Longer Fixation Times During Reading Are Correlated With Decreased Connectivity in Cognitive-Control Brain Regions During Rest in Children

Dyslexia, or reading difficulty (RD), is characterized by slow, inaccurate reading and accompanied by deficit in executive functions (EF) and altered functional connectivity (FC) in the related networks (i.e., cingulo-opercular). Individuals with RD also present with altered oculomotor gaze patterns that include longer fixation times. The researchers examined the relationship between fixation times and FC of neural circuits related to EF during rest in children with RD and typical readers. Nineteen children participated in a 10-min resting-state scan. FC analysis was performed with the anterior cingulate cortex (ACC), related to cognitive control, chosen as a seed. Fixation time during word reading was used as a covariate of interest. Results demonstrated that FC between the ACC and the left inferior frontal cortex pars triangularis and left inferior prefrontal cortex during rest were negatively correlated with fixation times during word reading. These exploratory results support the critical role for the cingulo-opercular network, which is related to cognitive control, in the reading process, and likely also in reading impairment.

Familial history of reading difficulty is associated with diffused bilateral brain activation during reading and greater association with visual attention abilities

Reading difficulty (RD; or dyslexia) is a heritable condition characterized by slow, inaccurate reading accompanied by executive dysfunction, specifically with respect to visual attention. The current study was designed to examine the effect of familial history of RD on the relationship between reading and visual attention abilities in children with RD using a functional MRI reading task. Seventy-one children with RD participated in the study. Based on parental reports of the existence of RD in one or both of each child's parents, children with RD were divided into two groups: (1) those with a familial history of RD and (2) those without a familial history of RD. Reading and visual attention measures were collected from all participants. Functional MRI data during word reading was acquired in 30 participants of the entire cohort. Children with or without a familial history of RD demonstrated below-average reading and visual attention scores, with greater interaction between these measures in the group with a familial history of RD. Greater bilateral and diffused activation during word reading also were found in this group. We suggest that a familial history of RD is related to greater association between lower reading abilities and visual attention abilities. Parental history of RD therefore may be an important preschool screener (before reading age) to prompt early intervention focused on executive functions and reading-related skills.

Exploring the Link between Visual Perception, Visual-Motor Integration, and Reading in Normal Developing and Impaired Children using DTVP-2

Reading is known to be primarily a linguistic task. However, to successfully decode written words, children also need to develop good visual-perception skills. Furthermore, motor skills are implicated in letter recognition and reading acquisition. Three studies have been designed to determine the link between reading, visual perception, and visual-motor integration using the Developmental Test of Visual Perception version 2 (DTVP-2). Study 1 tests how visual perception and visual-motor integration in kindergarten predict reading outcomes in Grade 1, in typical developing children. Study 2 is aimed at finding out if these skills can be seen as clinical markers in dyslexic children (DD). Study 3 determines if visual-motor integration and motor-reduced visual perception can distinguish DD children according to whether they exhibit or not developmental coordination disorder (DCD). Results showed that phonological awareness and visual-motor integration predicted reading outcomes one year later. DTVP-2 demonstrated similarities and differences in visual-motor integration and motor-reduced visual perception between children with DD, DCD, and both of these deficits. DTVP-2 is a suitable tool to investigate links between visual perception, visual-motor integration and reading, and to differentiate cognitive profiles of children with developmental disabilities (i.e. DD, DCD, and comorbid children). Copyright © 2017 John Wiley & Sons, Ltd.

Evidence for a differential interference of noise in sub-lexical and lexical reading routes in healthy participants and dyslexics

The ineffective exclusion of surrounding noise has been proposed to underlie the reading deficits in developmental dyslexia. However, previous studies supporting this hypothesis focused on low-level visual tasks, providing only an indirect link of noise interference on reading processes. In this study, we investigated the effect of noise on regular, irregular, and pseudoword reading in 23 dyslexic children and 26 age- and IQ-matched controls, by applying the white noise displays typically used to validate this theory to a lexical decision task. Reading performance and eye movements were measured. Results showed that white noise did not consistently affect dyslexic readers more than typical readers. Noise affected more dyslexic than typical readers in terms of reading accuracy, but it affected more typical than dyslexic readers in terms of response time and eye movements (number of fixations and regressions). Furthermore, in typical readers, noise affected more the speed of reading of pseudowords than real words. These results suggest a particular impact of noise on the sub-lexical reading route where attention has to be deployed to individual letters. The use of a lexical route would reduce the effect of noise. A differential impact of noise between words and pseudowords may therefore not be evident in dyslexic children if they are not yet proficient in using the lexical route. These findings indicate that the type of reading stimuli and consequent reading strategies play an important role in determining the effects of noise interference in reading processing and should be taken into account by further studies.

Visual Attention Processes and Oculomotor Control in Autism Spectrum Disorder: A Brief Review and Future Directions

Autism spectrum disorder (ASD) is defined as persistent deficits in social communication and social interaction, and restricted, repetitive patterns of behavior, interests or activities Diagnostic and Statistical Manual of Mental Disorders (5th ed., DSM-5; American Psychiatric Association, 2013). However, individuals with ASD show clearly atypical visual patterns. So far, indications of abnormal visual attention and oculomotor control concerning stimuli independent of social function in ASD have been found. The same findings have been shown in individuals suffering of other neurodevelopmental disorders (e.g., developmental coordination disorder and developmental dyslexia [DD]). Furthermore, visual attention processes and oculomotor control are supposed to be subserved by the magnocellular visual system, which has been found, in turn, to be dysfunctional in ASD and other neurodevelopmental disabilities (i.e., DD). The purpose of this article is to briefly review the link between oculomotor control and visual attention processes and ASD, and to discuss the specificity and overlap of eye movement findings between ASD and other neurodevelopmental disorders.

Too little or too much? Parafoveal preview benefits and parafoveal load costs in dyslexic adults

Two different forms of parafoveal dysfunction have been hypothesized as core deficits of dyslexic individuals: reduced parafoveal preview benefits ("too little parafovea") and increased costs of parafoveal load ("too much parafovea"). We tested both hypotheses in a single eye-tracking experiment using a modified serial rapid automatized naming (RAN) task. Comparisons between dyslexic and non-dyslexic adults showed reduced parafoveal preview benefits in dyslexics, without increased costs of parafoveal load. Reduced parafoveal preview benefits were observed in a naming task, but not in a silent letter-finding task, indicating that the parafoveal dysfunction may be consequent to the overload with extracting phonological information from orthographic input. Our results suggest that dyslexics' parafoveal dysfunction is not based on strict visuo-attentional factors, but nevertheless they stress the importance of extra-phonological processing. Furthermore, evidence of reduced parafoveal preview benefits in dyslexia may help understand why serial RAN is an important reading predictor in adulthood.

Impaired Oculomotor Behavior of Children with Developmental Dyslexia in Antisaccades and Predictive Saccades Tasks

Analysis of eye movement patterns during tracking tasks represents a potential way to identify differences in the cognitive processing and motor mechanisms underlying reading in dyslexic children before the occurrence of school failure. The current study aimed to evaluate the pattern of eye movements in antisaccades, predictive saccades and visually guided saccades in typical readers and readers with developmental dyslexia. The study included 30 children (age M = 11; SD = 1.67), 15 diagnosed with developmental dyslexia (DG) and 15 regular readers (CG), matched by age, gender and school grade. Cognitive assessment was performed prior to the eye-tracking task during which both eyes were registered using the Tobii® 1750 eye-tracking device. The results demonstrated a lower correct antisaccades rate in dyslexic children compared to the controls (p < 0.001, DG = 25%, CC = 37%). Dyslexic children also made fewer saccades in predictive latency (p < 0.001, DG = 34%, CG = 46%, predictive latency within −300–120 ms with target as 0 point). No between-group difference was found for visually guided saccades. In this task, both groups showed shorter latency for right-side targets. The results indicated altered oculomotor behavior in dyslexic children, which has been reported in previous studies. We extend these findings by demonstrating impaired implicit learning of target's time/position patterns in dyslexic children.

Pay Attention!: Sluggish Multisensory Attentional Shifting as a Core Deficit in Developmental Dyslexia

The aim of this review is to provide a background on the neurocognitive aspects of the reading process and review neuroscientific studies of individuals with developmental dyslexia, which provide evidence for amodal processing deficits. Hari, Renvall, and Tanskanen (2001) propose amodal sluggish attentional shifting (SAS) as a causal factor for temporal processing deficits in dyslexia. Undergirding this theory is the notion that when dyslexics are faced with rapid sequences of stimuli, their automatic attentional systems fail to disengage efficiently, which leads to difficulty when moving from one item to the next (Lallier et al., ). This results in atypical perception of rapid stimulus sequences. Until recently, the SAS theory, particularly the examination of amodal attentional deficits, was studied solely through the use of behavioural measures (Facoetti et al., ; Facoetti, Lorusso, Cattaneo, Galli, & Molteni, ). This paper examines evidence within the literature that provides a basis for further exploration of amodal SAS as an underlying deficit in developmental dyslexia.

Delayed Anticipatory Spoken Language Processing in Adults with Dyslexia—Evidence from Eye-tracking

It is now well established that anticipation of upcoming input is a key characteristic of spoken language comprehension. It has also frequently been observed that literacy influences spoken language processing. Here, we investigated whether anticipatory spoken language processing is related to individuals' word reading abilities. Dutch adults with dyslexia and a control group participated in two eye-tracking experiments. Experiment 1 was conducted to assess whether adults with dyslexia show the typical language-mediated eye gaze patterns. Eye movements of both adults with and without dyslexia closely replicated earlier research: spoken language is used to direct attention to relevant objects in the environment in a closely time-locked manner. In Experiment 2, participants received instructions (e.g., 'Kijk naar de(COM) afgebeelde piano(COM)', look at the displayed piano) while viewing four objects. Articles (Dutch 'het' or 'de') were gender marked such that the article agreed in gender only with the target, and thus, participants could use gender information from the article to predict the target object. The adults with dyslexia anticipated the target objects but much later than the controls. Moreover, participants' word reading scores correlated positively with their anticipatory eye movements. We conclude by discussing the mechanisms by which reading abilities may influence predictive language processing.

Investigating graph comprehension in students with dyslexia: an eye tracking study

The purpose of this study was to examine graph comprehension in college students with developmental dyslexia. We investigated how graph types (line, vertical bar, and horizontal bar graphs), graphic patterns (single and double graphic patterns), and question types (point locating and comparison questions) differentially affect graph comprehension of students with and without dyslexia. Groups were compared for (1) reaction times for answering comprehension questions based on graphed data and (2) eye gaze times for specific graph subregions (x-axis, y-axis, pattern, legend, question, and answer). Dyslexic readers were significantly slower in their graph comprehension than their peers with group differences becoming more robust with the increasing complexity of graphs and tasks. In addition, dyslexic readers' initial eye gaze viewing times for linguistic subregions (question and answer) and total viewing times for both linguistic (question and answer) and nonlinguistic (pattern) subregions were significantly longer than their control peers' times. In spite of using elementary-level paragraphs for comprehension and simple graph forms, young adults with dyslexia needed more time to process linguistic and nonlinguistic stimuli. These findings are discussed relative to theories proposed to address fundamental processing deficits in individuals with dyslexia.

Writing to dictation and handwriting performance among Chinese children with dyslexia: relationships with orthographic knowledge and perceptual-motor skills

The purpose of this study was to investigate the relationships between writing to dictation, handwriting, orthographic, and perceptual-motor skills among Chinese children with dyslexia. A cross-sectional design was used. A total of 45 third graders with dyslexia were assessed. Results of stepwise multiple regression models showed that Chinese character naming was the only predictor associated with word dictation (β=.32); handwriting speed was related to deficits in rapid automatic naming (β=-.36) and saccadic efficiency (β=-.29), and visual-motor integration predicted both of the number of characters exceeded grid (β=-.41) and variability of character size (β=-.38). The findings provided support to a multi-stage working memory model of writing for explaining the possible underlying mechanism of writing to dictation and handwriting difficulties.

E-readers are more effective than paper for some with dyslexia

E-readers are fast rivaling print as a dominant method for reading. Because they offer accessibility options that are impossible in print, they are potentially beneficial for those with impairments, such as dyslexia. Yet, little is known about how the use of these devices influences reading in those who struggle. Here, we observe reading comprehension and speed in 103 high school students with dyslexia. Reading on paper was compared with reading on a small handheld e-reader device, formatted to display few words per line. We found that use of the device significantly improved speed and comprehension, when compared with traditional presentations on paper for specific subsets of these individuals: Those who struggled most with phoneme decoding or efficient sight word reading read more rapidly using the device, and those with limited VA Spans gained in comprehension. Prior eye tracking studies demonstrated that short lines facilitate reading in dyslexia, suggesting that it is the use of short lines (and not the device per se) that leads to the observed benefits. We propose that these findings may be understood as a consequence of visual attention deficits, in some with dyslexia, that make it difficult to allocate attention to uncrowded text near fixation, as the gaze advances during reading. Short lines ameliorate this by guiding attention to the uncrowded span.