Dyslexics’ Fragile Oculomotor Control Is Further Destabilized by Increased Text Difficulty

Dyslexic adolescents demonstrate deficits in word decoding, recognition, and oculomotor coordination as compared to healthy controls. Our lab recently showed intrinsic deficits in large saccades and vergence movements with a Remobi device independent from reading. This shed new light on the field of dyslexia, as it has been debated in the literature whether the deficits in eye movements are a cause or consequence of reading difficulty. The present study investigates how these oculomotor problems are compensated for or aggravated by text difficulty. A total of 46 dyslexic and 41 non-dyslexic adolescents’ eye movements were analyzed while reading L’Alouette, a dyslexia screening test, and 35 Kilos D’Espoir, a children’s book with a reading age of 10 years. While reading the more difficult text, dyslexics made more mistakes, read slower, and made more regressive saccades; moreover, they made smaller amplitude saccades with abnormal velocity profiles (e.g., higher peak velocity but lower average velocity) and significantly higher saccade disconjugacy. While reading the simpler text, these differences persisted; however, the difference in saccade disconjugacy, although present, was no longer significant, nor was there a significant difference in the percentage of regressive saccades. We propose that intrinsic eye movement abnormalities in dyslexics such as saccade disconjugacy, abnormal velocity profiles, and cognitively associated regressive saccades can be particularly exacerbated if the reading text relies heavily on word decoding to extract meaning; increased number of regressive saccades are a manifestation of reading difficulty and not a problem of eye movement per se. These interpretations are in line with the motor theory of visual attention and our previous research describing the relationship between binocular motor control, attention, and cognition that exists outside of the field of dyslexia.

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Predicting Dyslexia and Reading Speed in Adolescents from Eye Movements in Reading and Non-Reading Tasks: A Machine Learning Approach

Brain Sciences ◽

10.3390/brainsci11101337 ◽

2021 ◽

Vol 11 (10) ◽

pp. 1337

Author(s):

Alae Eddine El Hmimdi ◽

Lindsey M Ward ◽

Themis Palpanas ◽

Zoï Kapoula

Keyword(s):

Machine Learning ◽

Eye Movements ◽

Eye Movement ◽

Reading Speed ◽

Reading Difficulty ◽

Word Decoding ◽

Applied Machine Learning ◽

Movement Data ◽

Using Data ◽

Meaningful Text

There is evidence that abnormalities in eye movements exist during reading in dyslexic individuals. A few recent studies applied Machine Learning (ML) classifiers to such eye movement data to predict dyslexia. A general problem with these studies is that eye movement data sets are limited to reading saccades and fixations that are confounded by reading difficulty, e.g., it is unclear whether abnormalities are the consequence or the cause of reading difficulty. Recently, Ward and Kapoula used LED targets (with the REMOBI & AIDEAL method) to demonstrate abnormalities of large saccades and vergence eye movements in depth demonstrating intrinsic eye movement problems independent from reading in dyslexia. In another study, binocular eye movements were studied while reading two texts: one using the “Alouette” text, which has no meaning and requires word decoding, the other using a meaningful text. It was found the Alouette text exacerbates eye movement abnormalities in dyslexics. In this paper, we more precisely quantify the quality of such eye movement descriptors for dyslexia detection. We use the descriptors produced in the four different setups as input to multiple classifiers and compare their generalization performances. Our results demonstrate that eye movement data from the Alouette test predicts dyslexia with an accuracy of 81.25%; similarly, we were able to predict dyslexia with an accuracy of 81.25% when using data from saccades to LED targets on the Remobi device and 77.3% when using vergence movements to LED targets. Noticeably, eye movement data from the meaningful text produced the lowest accuracy (70.2%). In a subsequent analysis, ML algorithms were applied to predict reading speed based on eye movement descriptors extracted from the meaningful reading, then from Remobi saccade and vergence tests. Remobi vergence eye movement descriptors can predict reading speed even better than eye movement descriptors from the meaningful reading test.

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Age Differences in Eye Movements During Reading: Degenerative Problems or Compensatory Strategy?

European Psychologist ◽

10.1027/1016-9040/a000344 ◽

2019 ◽

Vol 24 (4) ◽

pp. 297-311

Author(s):

José David Moreno ◽

José A. León ◽

Lorena A. M. Arnal ◽

Juan Botella

Keyword(s):

Eye Movements ◽

Eye Movement ◽

Meta Analysis ◽

Age Groups ◽

Behavioral Changes ◽

Aging Effects ◽

Movement Data ◽

Sentence Reading ◽

The Difference ◽

Eye Movements During Reading

Abstract. We report the results of a meta-analysis of 22 experiments comparing the eye movement data obtained from young ( Mage = 21 years) and old ( Mage = 73 years) readers. The data included six eye movement measures (mean gaze duration, mean fixation duration, total sentence reading time, mean number of fixations, mean number of regressions, and mean length of progressive saccade eye movements). Estimates were obtained of the typified mean difference, d, between the age groups in all six measures. The results showed positive combined effect size estimates in favor of the young adult group (between 0.54 and 3.66 in all measures), although the difference for the mean number of fixations was not significant. Young adults make in a systematic way, shorter gazes, fewer regressions, and shorter saccadic movements during reading than older adults, and they also read faster. The meta-analysis results confirm statistically the most common patterns observed in previous research; therefore, eye movements seem to be a useful tool to measure behavioral changes due to the aging process. Moreover, these results do not allow us to discard either of the two main hypotheses assessed for explaining the observed aging effects, namely neural degenerative problems and the adoption of compensatory strategies.

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Abstract W P140: Post-stroke Oculomotor Abnormalities evident during Objective Eye Tracking but Not under Clinical Assessment

Stroke ◽

10.1161/str.46.suppl_1.wp140 ◽

2015 ◽

Vol 46 (suppl_1) ◽

Author(s):

John-Ross Rizzo ◽

Todd Hudson ◽

Briana Kowal ◽

Michal Wiseman ◽

Preeti Raghavan

Keyword(s):

Motor Control ◽

Eye Movements ◽

Eye Movement ◽

Oculomotor Control ◽

Healthy Controls ◽

Visually Guided ◽

Stroke Patients ◽

Movement Execution ◽

Post Stroke ◽

Control Post

Introduction: Visual abnormalities and manual motor control have been studied extensively after stroke, but an understanding of oculomotor control post-stroke has not. Recent studies have revealed that in visually guided reaches arm movements are planned during eye movement execution, which may contribute to increased task complexity. In fact, in healthy controls during visually guided reaches, the onset of eye movement is delayed, its velocity reduced, and endpoint errors are larger relative to isolated eye movements. Our objective in this experiment was to examine the temporal properties of eye movement execution for stroke patients with no diagnosed visual impairment. The goal is to improve understanding of oculomotor control in stroke relative to normal function, and ultimately further understand its coordination with manual motor control during joint eye and hand movements. We hypothesized that stroke patients would show abnormal initiation or onset latency for saccades made in an eye movement task, as compared to healthy controls. Methods: We measured the kinematics of eye movements during point-to-point saccades; there was an initial static, fixation point and the stimulus was a flashed target on a computer monitor. We used a video-based eye tracker for objective recording of the eye at a sampling frequency of 2000 Hz (SR Research, Eyelink). 10 stroke subjects, over 4 months from injury and with no diagnosed visual impairment, and 10 healthy controls completed 432 saccades in a serial fashion. Results: Stroke patients had significantly faster onset latencies as compared to healthy controls during saccades (99.5ms vs. 245.2ms, p=0.00058). Conclusion: A better understanding of the variations in oculomotor control post-stroke, which may go unnoticed during clinical assessment, may improve understanding of how eye control synchronizes with arm or manual motor control. This knowledge could assist in tailoring rehabilitative strategies to amplify motor recovery. For next steps, we will perform objective eye and hand recordings during visually guided reaches post-stroke to better understand the harmonization or lack thereof after neurologic insult.

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Biosignal-Based Attention Monitoring to Support Nuclear Operator Safety-Relevant Tasks

Frontiers in Computational Neuroscience ◽

10.3389/fncom.2020.596531 ◽

2020 ◽

Vol 14 ◽

Author(s):

Jung Hwan Kim ◽

Chul Min Kim ◽

Eun-Soo Jung ◽

Man-Sung Yim

Keyword(s):

Eye Movements ◽

Eye Movement ◽

Nuclear Power ◽

Physical Work ◽

Support Vector ◽

Remote Measurement ◽

Nuclear Operator ◽

Human Errors ◽

Significant Difference ◽

Operator Safety

In the main control room (MCR) of a nuclear power plant (NPP), the quality of an operator's performance can depend on their level of attention to the task. Insufficient operator attention accounted for more than 26% of the total causes of human errors and is the highest category for errors. It is therefore necessary to check whether operators are sufficiently attentive either as supervisors or peers during reactor operation. Recently, digital control technologies have been introduced to the operating environment of an NPP MCR. These upgrades are expected to enhance plant and operator performance. At the same time, because personal computers are used in the advanced MCR, the operators perform more cognitive works than physical work. However, operators may not consciously check fellow operators' attention in this environment indicating potentially higher importance of the role of operator attention. Therefore, remote measurement of an operator's attention in real time would be a useful tool, providing feedback to supervisors. The objective of this study is to investigate the development of quantitative indicators that can identify an operator's attention, to diagnose or detect a lack of operator attention thus preventing potential human errors in advanced MCRs. To establish a robust baseline of operator attention, this study used two of the widely used biosignals: electroencephalography (EEG) and eye movement. We designed an experiment to collect EEG and eye movements of the subjects who were monitoring and diagnosing nuclear operator safety-relevant tasks. There was a statistically significant difference between biosignals with and without appropriate attention. Furthermore, an average classification accuracy of about 90% was obtained by the k-nearest neighbors and support vector machine classifiers with a few EEG and eye movements features. Potential applications of EEG and eye movement measures in monitoring and diagnosis tasks in an NPP MCR are also discussed.

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Comparisons of Proximal Vergence Measures

Vision Development & Rehabilitation ◽

10.31707/vdr2020.6.3.p252 ◽

2020 ◽

pp. 252-263

Keyword(s):

Eye Movement ◽

Refractive Error ◽

Measurement Method ◽

Clinical Utility ◽

T Test ◽

Significant Difference ◽

The Mean ◽

The Difference ◽

Paired T Test ◽

Vergence Eye Movement

Background: Proximal vergence is defined as a vergence eye movement subtype driven by an “awareness of nearness”. The purpose of this experiment was to compare values of proximal vergence calculated with and without measures of accommodation to assess the clinical utility of each measurement method. Methods: Thirteen participants between the ages of 22 and 37 (mean = 28.5 ± 4.5 years) were enrolled. The distance and near heterophoria were measured using the Modified Thorington technique. The near heterophoria was measured under three randomized viewing conditions (no lenses, +1.00D lenses, +2.50D lenses). Refractive error was measured with an autorefractor. Proximal vergence was calculated as the difference in calculated (far-near) and gradient (+1.00) stimulus AC/A ratios (stimulus AC/A differencing method), the difference in calculated and gradient response AC/A ratios (response AC/A differencing method), and the change in vergence from distance to near with the +2.50D lenses (uncorrected +2.50D method). This latter value was also corrected for any active accommodation with +2.50D lenses (corrected +2.50D method). Results: The mean proximal vergence values (Δ) were 7.82 ± 5.98 (stimulus AC/A differencing method), 8.29 ± 3.30 (response AC/A differencing method), 6.23 ± 3.52 (uncorrected +2.50D method), and 5.13 ± 2.98 (corrected +2.50D method). The only comparison that showed both a significant correlation (p<0.05) and a non-significant difference from the paired t-test (p>0.05) was that between the stimulus AC/A differencing method and the uncorrected +2.50D method. Conclusions: When response accommodation was accounted for, differences occurred in the mean proximal values obtained with the various methods. The means of the methods most likely to be used clinically (stimulus AC/A differencing method and uncorrected +2.50D method) were similar, although some individuals demonstrated significant differences between these methods.

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Perceptual Difficulty Persistently Increases Dominance in Binocular Rivalry—Even Without a Task

Perception ◽

10.1177/0301006621999929 ◽

2021 ◽

Vol 50 (4) ◽

pp. 343-366

Author(s):

Wolfgang Einhäuser ◽

Annalena Sandrock ◽

Alexander C. Schütz

Keyword(s):

Eye Movements ◽

Binocular Rivalry ◽

Oculomotor Control ◽

Task Instruction ◽

Perceptual Task ◽

Major Objective ◽

Task Relevance ◽

Perceptual Difficulty ◽

The Difference ◽

Reduction Of Uncertainty

A major objective of perception is the reduction of uncertainty about the outside world. Eye-movement research has demonstrated that attention and oculomotor control can subserve the function of decreasing uncertainty in vision. Here, we ask whether a similar effect exists for awareness in binocular rivalry, when two distinct stimuli presented to the two eyes compete for awareness. We tested whether this competition can be biased by uncertainty about the stimuli and their relevance for a perceptual task. Specifically, we have stimuli that are perceptually difficult (i.e., carry high perceptual uncertainty) compete with stimuli that are perceptually easy (low perceptual uncertainty). Using a no-report paradigm and reading the dominant stimulus continuously from the observers’ eye movements, we find that the perceptually difficult stimulus becomes more dominant than the easy stimulus. This difference is enhanced by the stimuli’s relevance for the task. In trials with task, the difference in dominance emerges quickly, peaks before the response, and then persists throughout the trial (further 10 s). However, the difference is already present in blocks before task instruction and still observable when the stimuli have ceased to be task relevant. This shows that perceptual uncertainty persistently increases perceptual dominance, and this is magnified by task relevance.

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EXPRESS: Eye Movement Patterns to Social and Non-social Cues in Early Deaf Adults

Quarterly Journal of Experimental Psychology ◽

10.1177/1747021821998511 ◽

2021 ◽

pp. 174702182199851

Author(s):

Claudia Bonmassar ◽

Francesco Pavani ◽

Alessio Di Renzo ◽

Cristina Caselli ◽

Wieske van Zoest

Keyword(s):

Eye Movements ◽

Eye Movement ◽

Movement Pattern ◽

Stimulus Onset ◽

Landing Position ◽

The Gaze ◽

Cue Validity ◽

Deaf Adults ◽

The Difference ◽

Onset Asynchrony

Previous research on covert orienting to the periphery suggested that early profound deaf adults were less susceptible to uninformative gaze cues, though were equally or more affected by non-social arrow cues. The aim of the present work was to investigate whether spontaneous eye movement behaviour helps explain the reduced impact of the social cue in deaf adults. We tracked the gaze of 25 early profound deaf and 25 age-matched hearing observers performing a peripheral discrimination task with uninformative central cues (gaze vs. arrow), stimulus-onset asynchrony (250 vs. 750 ms) and cue-validity (valid vs. invalid) as within-subject factors. In both groups, the cue-effect on RT was comparable for the two cues, although deaf observers responded significantly slower than hearing controls. While deaf and hearing observers eye movement pattern looked similar when the cue was presented in isolation, deaf participants made significantly eye movements than hearing controls once the discrimination target appeared. Notably, further analysis of eye movements in the deaf group revealed that independent of cue-type, cue-validity affected saccade landing position, while latency was not modulated by these factors. Saccade landing position was also strongly related to the magnitude of the validity effect on RT, such that the greater the difference in saccade landing position between invalid and valid trials, the greater the difference in manual RT between invalid and valid trials. This work suggests that the contribution of overt selection in central cueing of attention is more prominent in deaf adults and helps determine the manual performance, irrespective of cue-type.

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Abstracts of the 13th European Conference on Eye Movements 2005

Journal of Eye Movement Research ◽

10.16910/jemr.1.4.1 ◽

2005 ◽

Vol 1 (4) ◽

Author(s):

Marina Groner ◽

Rudolf Groner ◽

R. Müri ◽

Kazuo Koga ◽

Simon Raess ◽

...

Keyword(s):

Eye Movements ◽

Eye Movement ◽

Wide Spectrum ◽

Oculomotor Control ◽

Online Journal ◽

Historical Building ◽

Planning Stage ◽

European Conference ◽

The People ◽

University Of Bern

This issue contains the abstracts submitted for presentation at the Thirteenth European Conference on Eye Movements (ECEM13), Bern, August 14 – 18, 2005, and reviewed by the Scientific Board, consisting of W. Becker, Ulm; C.J. Erkelens, Utrecht; J.M. Findlay, Durham; A.G. Gale, Derby; C.W. Hess, Bern; J. Hyönä, Turku; A. Kennedy, Dundee; K. Koga, Nagoya; G. Lüer, Göttingen; M. Menozzi, Zürich; W. Perrig, Bern; G. d’Ydewalle, Leuven; D. Zambarbieri, Pavia. A quarter of a century ago, in 1980 initiated by Rudolf Groner and Dieter Heller, a transdisciplinary network called European Group of Scientists active in Eye Movement Research was founded. This group included scientists who used eye movement registration as a research tool and developed models based on oculomotor data obtained from a wide spectrum of phenomena, ranging from the neurophysiological to the perceptual and the cognitive level. The group was intended to serve the purpose of (1) exchanging information about current research, equipment and software, (2) organizing a conference (ECEM) at a different location all over Europe every other year. Over the years ECEM has grown. At the first conference in Bern the relatively small number of participants made it possible for the organisers to avoid conflicting parallel sessions, whereas with the ECEM’s steady growth, the introduction of parallel sessions soon became necessary. Although we are very happy about this year’s new record of 273 scientific contributions, we regret at the same time that this large number of participants necessitated the introduction of no less than four parallel sessions for oral presentations. Part of the ECEM culture are the books with a selection of edited contributions which have traditionally always been published after the conferences. Unfortunately, over the years the sale prices of books have become prohibitively expensive and book chapters have increasingly been given a low rating in comparison to publications in peer reviewed journals. As a consequence of this trend, we are now considering to launch an online journal Eye Movement Research which would publish scientific papers either on the base of individual submissions by the authors or as a follow-up of workshops or thematic sessions at ECEM. In either case, a fair peer reviewing process should guarantee a high quality of the contributions. Acknowledgements Last but not least, we are happy to express our deep gratitude to the main sponsors of our conference and to all the people who helped to keep it going. The Max and Elsa Beer-Brawand Foundation generously funded the invited speakers. The Swiss Academy of Humanities and Social Sciences (SAGW) sponsored the organization of workshops and made it possible for us to reduce fees for students. Novartis Neuroscience sponsored the reception at the Zentrum Paul Klee Bern. The University of Bern hosted the conference in its magnificent historical building. A team of devoted young scientists acted as staff during the conference: Eva Siegenthaler, Liliane Braun, Miriam Lörtscher, Esther Schollerer, Daniel Stricker, Simon Raess, Philipp Sury, Bartholomäus Wissmath, Linda Bodmer, Martina Brunnthaler, Daniela Häberli, Nadine Messerli, Felicie Notter, Didier Plaschy, Svetlana Ognjanovi, David Weibel, Yves Steiner and Dominik Moser. We dedicate this book to the memory of two important men in eye movement research: Dieter Heller as one of the founders of the ECEM group, and Lawrence W. Stark as pioneer in cognitive modelling of oculomotor control. In an early planning stage of ECEM13 both had been invited as keynote speakers, but their untimely death made this plan impossible. In many sessions of ECEM13 the influence of their work will prevail.

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Visual word recognition and oculomotor control in reading

Behavioral and Brain Sciences ◽

10.1017/s0140525x03320102 ◽

2003 ◽

Vol 26 (4) ◽

pp. 487-488 ◽

Cited By ~ 3

Author(s):

Lynn Huestegge ◽

Jonathan Grainger ◽

Ralph Radach

Keyword(s):

Eye Movements ◽

Eye Movement ◽

Word Processing ◽

Movement Control ◽

Verbal Description ◽

Oculomotor Control ◽

Central Component ◽

Computational Implementation ◽

Processing Module ◽

Processing Mechanism

A central component in the E-Z Reader model is a two-stage word processing mechanism made responsible for both the triggering of eye movements and sequential shifts of attention. We point to problems with both the verbal description of this mechanism and its computational implementation in the simulation. As an alternative, we consider the use of a connectionist processing module in combination with a more indirect form of cognitive eye-movement control.

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Investigating the Relationship Between Eye Movement and Brain Wave Activity Using Video Games: Pilot Study (Preprint)

10.2196/preprints.8908 ◽

2017 ◽

Author(s):

Chaoguang Wang ◽

Gino Yu

Keyword(s):

Eye Movements ◽

Eye Movement ◽

Video Game ◽

Spectral Power ◽

Brain Wave ◽

Gamma Frequency ◽

Lateral Eye ◽

Beta Power ◽

Significant Difference ◽

The Relationship

BACKGROUND All eye movements are related in one way or another to our mental processes with lateral eye movements being associated with the different hemispheres of the brain. Eye movement techniques form the basis of eye movement desensitization and reprocessing therapy, wherein forced eye movements activate neurological pathways to treat the subject. OBJECTIVE The objective of our study was to examine the relationship between players' eye movements and their brain wave activities using a video game. METHODS We used similar eye movement techniques in the form of a video game called Lifeguard that could potentially stimulate different eye movement mode and create a more engaging experience for the user. By designing an experiment, we further explored the differences in electroencephalogram spectral power activity for the alpha, beta, theta, delta, and gamma frequency bands in Lifeguard and Tetris. RESULTS The game based on eye movement technologies resulted in decreased delta power and increased beta power, but significant difference between 2 games was not found. CONCLUSIONS The applied uses of this research could mean that eye movement desensitization and reprocessing can be conducted in a more fun and engaging way through the use of gaming technology.

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