scholarly journals Reading Specific Small Saccades Predict Individual Phonemic Awareness and Reading Speed

2021 ◽  
Vol 15 ◽  
Author(s):  
Samy Rima ◽  
Michael C. Schmid
Keyword(s):  
Eye Movements ◽  
Short Story ◽  
Phonemic Awareness ◽  
Developmental Dyslexia ◽  
Reading Skill ◽  
Fundamental Aspect ◽  
Fixational Eye Movements ◽  
Free Viewing ◽  
Wide Range ◽  
Fixational Saccades

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.

scholarly journals Fixation eye movement abnormalities and stereopsis recovery following strabismus repair

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Talora L. Martin ◽  
Jordan Murray ◽  
Kiran Garg ◽  
Charles Gallagher ◽  
Aasef G. Shaikh ◽  
...  
Keyword(s):  
Eye Movements ◽  
Eye Movement ◽  
Functional Improvement ◽  
Slow Phase ◽  
Fixational Eye Movements ◽  
Movement Characteristics ◽  
Adaptive Mechanisms ◽  
Before And After ◽  
Gaze Holding ◽  
Fixational Saccades

AbstractWe evaluated the effects of strabismus repair on fixational eye movements (FEMs) and stereopsis recovery in patients with fusion maldevelopment nystagmus (FMN) and patients without nystagmus. Twenty-one patients with strabismus, twelve with FMN and nine without nystagmus, were tested before and after strabismus repair. Eye-movements were recorded during a gaze-holding task under monocular viewing conditions. Fast (fixational saccades and quick phases of nystagmus) and slow (inter-saccadic drifts and slow phases of nystagmus) FEMs and bivariate contour ellipse area (BCEA) were analyzed in the viewing and non-viewing eye. Strabismus repair improved the angle of strabismus in subjects with and without FMN, however patients without nystagmus were more likely to have improvement in stereoacuity. The fixational saccade amplitudes and intersaccadic drift velocities in both eyes decreased after strabismus repair in subjects without nystagmus. The slow phase velocities were higher in patients with FMN compared to inter-saccadic drifts in patients without nystagmus. There was no change in the BCEA after surgery in either group. In patients without nystagmus, the improvement of the binocular function (stereopsis), as well as decreased fixational saccade amplitude and intersaccadic drift velocity, could be due, at least partially, to central adaptive mechanisms rendered possible by surgical realignment of the eyes. The absence of improvement in patients with FMN post strabismus repair likely suggests the lack of such adaptive mechanisms in patients with early onset infantile strabismus. Assessment of fixation eye movement characteristics can be a useful tool to predict functional improvement post strabismus repair.

Abnormal fixational eye movements in strabismus

2017 ◽  
Vol 102 (2) ◽  
pp. 253-259 ◽  
Author(s):  
Fatema F Ghasia ◽  
Jorge Otero-Millan ◽  
Aasef G Shaikh
Keyword(s):  
Eye Movements ◽  
Large Angle ◽  
Fine Tuning ◽  
Eye Position ◽  
Visually Guided ◽  
Binocular Fusion ◽  
The Gaze ◽  
Fixational Eye Movements ◽  
The Stability ◽  
Fixational Saccades

IntroductionFixational saccades are miniature eye movements that constantly change the gaze during attempted visual fixation. Visually guided saccades and fixational saccades represent an oculomotor continuum and are produced by common neural machinery. Patients with strabismus have disconjugate binocular horizontal saccades. We examined the stability and variability of eye position during fixation in patients with strabismus and correlated the severity of fixational instability with strabismus angle and binocular vision.MethodsEye movements were measured in 13 patients with strabismus and 16 controls during fixation and visually guided saccades under monocular viewing conditions. Fixational saccades and intersaccadic drifts were analysed in the viewing and non-viewing eye of patients with strabismus and controls.ResultsWe found an increase in fixational instability in patients with strabismus compared with controls. We also found an increase in the disconjugacy of fixational saccades and intrasaccadic ocular drift in patients with strabismus compared with controls. The disconjugacy was worse in patients with large-angle strabismus and absent stereopsis. There was an increase in eye position variance during drifts in patients with strabismus. Our findings suggest that both fixational saccades and intersaccadic drifts are abnormal and likely contribute to the fixational instability in patients with strabismus.DiscussionFixational instability could be a useful tool for mass screenings of children to diagnose strabismus in the absence of amblyopia and latent nystagmus. The increased disconjugacy of fixational eye movements and visually guided saccades in patients with strabismus reflects the disruption of the fine-tuning of the motor and visual systems responsible for achieving binocular fusion in these patients.

scholarly journals Unchanging visions: the effects and limitations of ocular stillness

2017 ◽  
Vol 372 (1718) ◽  
pp. 20160204 ◽  
Author(s):  
Susana Martinez-Conde ◽  
Stephen L. Macknik
Keyword(s):  
Eye Movements ◽  
Retinal Vessels ◽  
Top Down ◽  
Ocular Fixation ◽  
Gaze Fixation ◽  
Fixational Eye Movements ◽  
Eye Motion ◽  
Fixational Saccades ◽  
Erasmus Darwin ◽  
Existing Data

Scientists have pondered the perceptual effects of ocular motion, and those of its counterpart, ocular stillness, for over 200 years. The unremitting ‘trembling of the eye’ that occurs even during gaze fixation was first noted by Jurin in 1738. In 1794, Erasmus Darwin documented that gaze fixation produces perceptual fading, a phenomenon rediscovered in 1804 by Ignaz Paul Vital Troxler. Studies in the twentieth century established that Jurin's ‘eye trembling’ consisted of three main types of ‘fixational’ eye movements, now called microsaccades (or fixational saccades), drifts and tremor. Yet, owing to the constant and minute nature of these motions, the study of their perceptual and physiological consequences has met significant technological challenges. Studies starting in the 1950s and continuing in the present have attempted to study vision during retinal stabilization—a technique that consists on shifting any and all visual stimuli presented to the eye in such a way as to nullify all concurrent eye movements—providing a tantalizing glimpse of vision in the absence of change. No research to date has achieved perfect retinal stabilization, however, and so other work has devised substitute ways to counteract eye motion, such as by studying the perception of afterimages or of the entoptic images formed by retinal vessels, which are completely stable with respect to the eye. Yet other research has taken the alternative tack to control eye motion by behavioural instruction to fix one's gaze or to keep one's gaze still, during concurrent physiological and/or psychophysical measurements. Here, we review the existing data—from historical and contemporary studies that have aimed to nullify or minimize eye motion—on the perceptual and physiological consequences of perfect versus imperfect fixation. We also discuss the accuracy, quality and stability of ocular fixation, and the bottom–up and top–down influences that affect fixation behaviour. This article is part of the themed issue ‘Movement suppression: brain mechanisms for stopping and stillness’.

scholarly journals Fixational eye movement waveforms in amblyopia: Characteristics of fast and slow eye movements

2019 ◽  
Vol 12 (6) ◽  
Author(s):  
Sarah Linda Kang ◽  
Sinem B. Beylergil ◽  
Jorge Otero-Millan ◽  
Aasef Shaikh ◽  
Fatema Ghasia
Keyword(s):  
Visual Acuity ◽  
Eye Movements ◽  
Eye Movement ◽  
Treatment Effectiveness ◽  
Eye Diseases ◽  
Fixational Eye Movements ◽  
Fixation Stability ◽  
Slow Eye Movements ◽  
Fixational Saccades ◽  
The Impact

Fixational eye movements comprise of fast microsaccades alternating with slow inter-saccadic drifts. These physiologic eye movements play an important role in visual perception.  Amblyopic patients are known to have fixation instability, particularly of the amblyopic eye. We examined eye movement abnormalities that contribute to this instability. We found that fixation stability is affected by the presence of fusion maldevelopment nystagmus (FMN). However, some amblyopes can have nystagmus without nasally directed slow phases and reversal in direction of the quick phase on ocular occlusion, features seen in FMN. In patients without nystagmus, we found increased amplitude of fixational saccades and inter-saccadic drifts. We categorized amblyopia patients by type (anisometropic, strabismic, or mixed) and eye movement waveform (no nystagmus, nystagmus without FMN, and FMN). We found specific fast and slow eye movement abnormalities of the fellow and amblyopic eye during fellow, amblyopic and both eyes viewing conditions across eye movement waveforms and types of amblyopia. These eye movement abnormalities can serve as biomarkers that can predict the impact of amblyopia as measured by visual acuity and stereopsis. Evaluation of fixational eye movements in amblyopia could be important to diagnose these common eye diseases and predict treatment effectiveness. 

scholarly journals UNDERGRADUATE LANGUAGE PROBLEMS IN SHORT STORY THROUGH CREATIVE INTERPRETATION

2015 ◽  
pp. 8-37
Author(s):  
Manal Mohammed Ben- Ahmeida ◽  
farhan Ali
Keyword(s):  
Creative Writing ◽  
Undergraduate Students ◽  
Short Story ◽  
English Language ◽  
Reading Skill ◽  
Reading And Writing ◽  
Wide Range ◽  
Language Problems ◽  
Efl Teachers ◽  
Teachers And Students

This paper is conducted to shed the light on English language problems Libyan undergraduate students face in short story through creative interpretation in reading and writing. Creative writing is a wide range of literature and it deals not only with language but also with the wide imagination of writers. However, it is well known that if language problems increase, then even the imagination cannot help because writing techniques and creativity go on the same path. It has always been a great help for the writers to organize and deliver their writing in a suitable form. Most Libyan students cannot, they have many problems in composing, therefore; when they are asked to conduct a creative writing task, they find it enormously difficult and challenging. Those who have the ability to produce are the talented and skillful ones. In this paper, the aim is to encourage and motivate Libyan students to be effected to creative reading and writing as well as grow their skills and talents. Furthermore, this paper will deal with language problems in reading and writing that are mostly common in all levels of learners, and it will focus mostly on the scope of short story. In addition, the purpose of this paper is to provide ideas, suggestions, and solutions according to the problems that are encountered throughout this study. Reading this paper, will help Libyan EFL teachers realize that creative writing is a talent or a skill that has to be practiced; therefore, we will provide ideas to help teachers avoid favoring students who have the talents and skills in reading and writing over others by treating them equally, helping them grow their ability in being creative. There are some important elements that will be discussed throughout this study and the most elements of all is for Libyan EFL teachers and students to understand that there is a significant relationship between what the learner writes and what he/she reads which is called creative reading. In this paper we will present how the reading skill is also neglected by Libyan students. Students do not read for interest unless they are forced to do so for different reasons. Reading skill is not practiced by Libyan students even in their first language. Unfortunately, Libya is a culture that does not encourage, support, facilitate and provide for reading. Therefore, in this paper, the aim is also to help Libyan students learn that reading someone's piece of work is an essential step for developing the skill of creative writing and that provides the history or background about the expected text, even an imagination for an inspired story. Furthermore, providing this paper is to help Libyan students believe that the more the learner reads, the more he/she writes and creates. We would like students to believe that inspiration and imagination are the path for a readable and meaningful story which leads the writer to creativity. And, we believe that if EFL teachers find a way to provide creativity, students will gain the knowledge needed to write and read creatively.

scholarly journals Fixational eye movements predict visual sensitivity

2015 ◽  
Vol 282 (1817) ◽  
pp. 20151568 ◽  
Author(s):  
Chris Scholes ◽  
Paul V. McGraw ◽  
Marcus Nyström ◽  
Neil W. Roach
Keyword(s):  
Eye Movements ◽  
Contrast Sensitivity ◽  
Visual Sensitivity ◽  
Support Vector ◽  
Good Prediction ◽  
Tight Coupling ◽  
Fixational Eye Movements ◽  
Visual Contrast ◽  
Good Prediction Accuracy ◽  
Fixational Saccades

During steady fixation, observers make small fixational saccades at a rate of around 1–2 per second. Presentation of a visual stimulus triggers a biphasic modulation in fixational saccade rate—an initial inhibition followed by a period of elevated rate and a subsequent return to baseline. Here we show that, during passive viewing, this rate signature is highly sensitive to small changes in stimulus contrast. By training a linear support vector machine to classify trials in which a stimulus is either present or absent, we directly compared the contrast sensitivity of fixational eye movements with individuals' psychophysical judgements. Classification accuracy closely matched psychophysical performance, and predicted individuals' threshold estimates with less bias and overall error than those obtained using specific features of the signature. Performance of the classifier was robust to changes in the training set (novel subjects and/or contrasts) and good prediction accuracy was obtained with a practicable number of trials. Our results indicate a tight coupling between the sensitivity of visual perceptual judgements and fixational eye control mechanisms. This raises the possibility that fixational saccades could provide a novel and objective means of estimating visual contrast sensitivity without the need for observers to make any explicit judgement.

scholarly journals Unrestricted eye movements strengthen causal connectivity from hippocampal to oculomotor regions during scene construction

2021 ◽  
Author(s):  
Natalia Ladyka-Wojcik ◽  
Zhong-Xu Liu ◽  
Jennifer D. Ryan
Keyword(s):  
Eye Movements ◽  
Visual Processing ◽  
Oculomotor System ◽  
Visual Input ◽  
Causal Modeling ◽  
Oculomotor Control ◽  
Visual Stream ◽  
Functional Connections ◽  
Free Viewing ◽  
Scene Construction

Scene construction is a key component of memory recall, navigation, and future imagining, and relies on the medial temporal lobes (MTL). A parallel body of work suggests that eye movements may enable the imagination and construction of scenes, even in the absence of external visual input. There are vast structural and functional connections between regions of the MTL and those of the oculomotor system. However, the directionality of connections between the MTL and oculomotor control regions, and how it relates to scene construction, has not been studied directly in human neuroimaging. In the current study, we used dynamic causal modeling (DCM) to investigate this relationship at a mechanistic level using a scene construction task in which participants' eye movements were either restricted (fixed-viewing) or unrestricted (free-viewing). By omitting external visual input, and by contrasting free- versus fixed- viewing, the directionality of neural connectivity during scene construction could be determined. As opposed to when eye movements were restricted, allowing free viewing during construction of scenes strengthened top-down connections from the MTL to the frontal eye fields, and to lower-level cortical visual processing regions, suppressed bottom-up connections along the visual stream, and enhanced vividness of the constructed scenes. Taken together, these findings provide novel, non-invasive evidence for the causal architecture between the MTL memory system and oculomotor system associated with constructing vivid mental representations of scenes.

scholarly journals Infants' eye movements during free-viewing as a window into the development of attention

2010 ◽  
Vol 7 (9) ◽  
pp. 998-998
Author(s):  
M. C. Frank ◽  
E. Vul ◽  
S. P. Johnson
Keyword(s):  
Eye Movements ◽  
Free Viewing
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