Zoi Kapoula

Recent studies applying machine learning (ML) to saccade and vergence eye movements have demonstrated the ability to distinguish individuals with dyslexia, learning disorders, or attention disorders from healthy individuals or those with other pathologies. Stroke patients are known to exhibit visual deficits and eye movement disorders. This study f...

The analysis of eye movements has proven valuable for understanding brain function and the neuropathology of various disorders. This research aims to utilize eye movement data analysis as a screening tool for differentiation between eight different groups of pathologies, including scholar, neurologic, and postural disorders. Leveraging a dataset fr...

The vestibular function is in synergism with the oculomotor vergence. Vertigo may be related to vergence disorders and conversely, vestibular pathologies may affect vergence. To consolidate this hypothesis, we conducted a study at the vestibular orthoptic clinic of the Bastogne Hospital. Fourteen patients with vertigo history appearing 2 weeks to 8...

Self-supervised learning (SSL) has gained significant attention in the past decade for its capacity to utilize non-annotated datasets to learn meaningful data representations. In the medical domain, the challenge of constructing large annotated datasets presents a significant limitation, rendering SSL an ideal approach to address this constraint. I...

In this study, the challenges posed by limited annotated medical data in the field of eye movement AI analysis are addressed through the introduction of a novel physiologically based gaze data augmentation library. Unlike traditional augmentation methods, which may introduce artifacts and alter pathological features in medical datasets, the propose...

Early detection of dyslexia and learning disorders is vital for avoiding a learning disability, as well as supporting dyslexic students by tailoring academic programs to their needs. Several studies have investigated using supervised algorithms to screen dyslexia vs. control subjects; however, the data size and the conditions of data acquisition we...

In recent years, there has been a growing body of literature highlighting the relationship between presbycusis and consequences in areas other than hearing. In particular, presbycusis is linked to depression, dementia, and cognitive decline. Among this literature, the effect of hearing aids, currently the most common method of treating presbycusis,...

Dyslexic children have been shown to be more creative than their non-dyslexic counterparts. They have also been shown to have an abnormal oculomotor profile while viewing targets in free space, making vergence or saccadic eye movements while reading or when viewing Op art. They show a slower deceleration of their eye movements and a difficulty in c...

It is known that dyslexics present eye movement abnormalities. Previously, we have shown that eye movement abnormalities during reading or during saccade and vergence testing can predict dyslexia successfully. The current study further examines this issue focusing on eye movements during free exploration of paintings; the dataset was provided by a...

Op art was created, in part, to produce illusions of movement. Given that dyslexics have been shown to have impaired visuo-postural axis deficits, it may be possible that dyslexics see illusions different than their non-dyslexic peers. To test this theory, we measured eye movement and posture in 47 dyslexic (18 female, 29 male; mean age 15.4) and 4...

Multisensory integration is a capacity allowing us to merge information from different sensory modalities in order to improve the salience of the signal. Audiovisual integration is one of the most used kinds of multisensory integration, as vision and hearing are two senses used very frequently in humans. However, the literature regarding age-relate...

Introduction La presbyacousie touche 65 % de personnes de plus de 70 ans. Il existe une association entre presbyacousie et déclin cognitif. Objectifs L’objectif est de mieux comprendre les mécanismes entre presbyacousie et attention via une étude des mouvements oculaires et d’ouvrir de nouvelles voies de recherches pour le diagnostic à la presbyac...

Though saccade and vergence eye movements are fundamental for everyday life, the way these movements change as we age has not been sufficiently studied. The present study examines the effect of age on vergence and saccade eye movement characteristics (latency, peak and average velocity, amplitude) and on audiovisual facilitation. We compare the res...

Age-related macular degeneration (ARMD) is one of the most debilitating eye-related illnesses worldwide. Eye-movement training is evolving to be a non-invasive, rapid, and effective method that is positively impacting vision and QoL (quality of life) in patients suffering from ARMD. This review aims to highlight why a greater adoption of eye-moveme...

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 rea...

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 literatur...

We studied the effects of viewing François Morellet's Triple X Neonly (2012) on postural control and subjective appreciation. Triple X consists of 6 neon tubes arranged in a corner into a triple X pattern. Twenty-one participants were asked to view it with only one eye open (monocularly) and with both eyes open (binocularly). Their average forward-...

Previous studies suggest vergence and saccade abnormalities in dyslexic adolescents. However, these studies are mainly clinically based and do not provide objective measurements of eye movements, but rather subjectively evaluate vergence using haplosopic conditions in which the two eyes are dissociated (via polarizers, prisms, or intermittent spect...

Background Previous clinical evaluations have demonstrated a difference in eye movements in healthy children compared to children with vertigo without vestibular pathology. It has also been previously shown that accommodation and vergence responses can be measured with remote haploscopic photo refractor (RHP) devices. We have developed a method, ca...

Interaction mechanisms between cognition and binocular motor control in reading saccades remain unclear. In this study we examine objectively saccades and fixations parameters during the Stroop test, involving three different levels of cognitive demand (reading, color denomination and interference). In addition, we experimentally induce accommodati...

Aim: Vergence insufficiency is a common oculomotor disorder which causes visual but also general, and even postural symptoms. This study aimed to characterise postural control of subjects with isolated vergence disorder and assess whether orthoptic therapy affects it. Method: Vergence disorders were evaluated and treated by orthoptists. Postural...

Abstract The estimation of Subjective Visual Vertical (SVV) involves the allocentric, gravitational and egocentric references, which are built by visual, vestibular and somatosensory afferents. Our goals were to assess the influence of plantar cutaneous afferents on the perception of SVV, and to see if there is a difference according to the efficie...

Painting is essentially a visual form of arts. Apparently, audition and the hearing system seem to be of no avail in the aesthetic experience felt by painters during the creative process of artistic visual patterns, and by beholders while painting viewing. But philosophers and modern neuroscience have challenged this kind of unimodal and classical...

This study is an in situ experiment carried out at the Grand Palais in Paris during the exhibition “Dynamo” in 2013. Visitors of the exhibition were asked to stand in quiet stance in the middle of Carsten Höller’s “Light Corner” (2001). This artwork, one of the first of the Dynamo exhibition, was a room (three walls, the fourth side being the entra...

Interpreting pre-existing pieces of architecture is not only a poetical matter that concerns theorists and historians. It is an important hermeneutical issue with many practical repercussions, especially when there is a need to intervene in valuable or historical buildings; it is also pertinent in what regards the didactics of architecture. We prop...

Interpreting pre-existing pieces of architecture is not only a poetical matter that concerns theorists and historians. It is an important hermeneutical issue with many practical repercussions, especially when there is a need to intervene in valuable or historical buildings; it is also pertinent in what regards the didactics of architecture. We prop...

Introduction: The purpose was to investigate the effect of vergence reeducation on postural control, in subjects with isolated vergence disorders. Material and methods: We studied the dynamics of vergence in 19 subjects (20-44 years old) using video-oculography (Eye See Cam). On the basis of orthoptic and symptomatology assessments, ten of the s...

L’objectif de l’étude était d’évaluer l’effet d’inserts plantaires fins sur le contrôle postural et sur les mouvements de vergence et de saccades en orthostatisme. Les performances de 36 sujets jeunes et sains ont été enregistrées à l’aide d’une plateforme de forces et d’un vidéo-oculomètre dans trois conditions : sans stimulation plantaire, ou ave...

Introduction : we assessed whether subjects with Plantar Exteroceptive Inefficiency (PEI), characterized by a Plantar Quotient (PQ) <100, are more unstable and have a less efficient control of vergence than subjects with a normal PQ (i.e. >100, NPQS). We also aimed at identifying which parameters of stability are affected by foam interposition with...

Nous avons évalué les effets de stimulations plantaires fines sur le contrôle postural et les mouvements oculaires de sujets jeunes et sains en orthostatisme. Les inserts plantaires améliorent la stabilité et modifient la répartition des phases de la vergence de manière spécifique selon la zone plantaire stimulée. Les stimulations internes limitent...

Introduction Some subjects have difficulty to integrate both visual and plantar inputs, showing at the same time a “postural blindness” and a Plantar Exteroceptive Inefficiency (PEI). The former corresponds to a better stability eyes closed (EC) than eyes open (EO), while the latter is defined as a better stability on foam than on firm ground. Clin...

Purpose: We hypothesized that saccade eye movement properties, particularly latency and binocular coordination, depend on vergence quality. Methods: We studied 11 students clinically diagnosed for vergence disorders versus 8 healthy controls. Rehabilitation of vergence disorders was done with a novel research-based method, using vergence in mids...

Are dyslexic children and teenagers particularly creative? Although controversial, several theories hypothesized putative neuro-physiological mechanisms: disequilibrium of magno- and parvo-cellular systems, the latter compensating weakness of the former, and inter-hemispheric connectivity difference. In this study, we further hypothesized a role of...

Les afférences cutanées plantaires influencent l’alignement binoculaire. Cela ne semble pas relever d’une situation physiologique, mais plutôt être la conséquence de la dysfonction somesthésique non douloureuse nommée « épine irritative d’appui plantaire". Celle-ci semble agir comme un bruit qui influence l’ajustement des phories horizontales. Ces...

Introduction Nos recherches préalables ont permis d’établir chez le sujet sain des régularités posturales, liées à la qualité des mouvements oculaires de vergence : meilleure performance posturale avec yeux ouverts que fermés, en fixation proche que lointaine. Or, les troubles de vergence sont fréquents. L’étude présente menée à l’hôpital, examine...

Introduction En présence du strabisme, la vision binoculaire unie, la vision de la profondeur et du relief sont affectées, ainsi que les mouvements de vergence. Le but de l’étude est d’investiguer l’impact de la chirurgie sur les capacités visuo-motrices et posturales. Patients et méthode L’étude porte sur 9 sujets ésotropes (6–17 ans), 6 exotrope...

We hypothesize that binocular coordination of saccades is based on continuous neuroplasticity involving interactions of saccades and vergence. To test this hypothesis we study reading saccades in young students who were diagnosed for vergence disorders before and after vergence rehabilitation. Following orthoptic evaluation and symptomatology scree...

In a previous experiment, we showed that among young and healthy subjects, thin plantar inserts improve postural control and modify vergence amplitudes. In this experiment, however, significant inter-individual variability was observed. We hypothesize that its origin could be attributed to a different reliance upon feet cutaneous afferents. In orde...

While the overall development of saccades in children has recently gained increasing interest, the precise characteristics of vertical saccades remain understudied. The few adult studies existing showed up/down anisotropies on various parameters. This study focuses on the development of vertical saccades and their interaction with vergence movement...

Clinical studies in non-specific chronic arthralgia and back pain seem to indicate an association between vertical heterophoria (VH – latent vertical retinal misalignment) and asymmetrical head rotation. Such clinical observations suggest a link between VH and head rotation, but this was never tested. The purpose of this study was to simulate a VH...

Purpose: We performed video-oculography to evaluate vergence eye movement abnormalities in students diagnosed clinically with vergence disorders. We tested the efficiency of a novel rehabilitation method and evaluated its benefits with video-oculography cross-correlated with clinical tests and symptomatology. Methods: A total of 19 students (20-...

Background and study hypothesis: Are dyslexic children and teenagers more creative than non-dyslexic children and teenagers? Whether creativity is higher in dyslexia, and whether this could be related to neurological development specific to the dyslexic disorder, or to compensatory strategies acquired later in life, remains unclear. Here, we sugge...

Introduction L’objectif est d’évaluer l’effet de stimulations plantaires fines sur la perception de la verticale visuelle (VVS) et le contrôle postural en vision proche (à 40 cm, convergence) et en vision lointaine (200 cm, divergence oculaire). Matériel et méthodes La perception de la verticale de 48 sujets asymptomatiques (25 ± 3,3 ans) a été év...

Purpose: Recent studies report a link between optometric results, learning disabilities, and problems in reading. This study examines the correlations between optometric tests of binocular vision, namely, of vergence and accommodation, reading speed, and cognitive executive functions as measured by the Stroop test. Methods: Fifty-one students (m...

The purpose of this study was to assess properties of vergence and saccade eye movements as well as posture in quiet stance, and the effects of thin plantar inserts upon postural and oculomotor control. The performances of 36 young healthy subjects were recorded by a force platform and an eye tracker in three testing conditions: without plantar sti...

Postural results. (XLS)

Eye movement results. (XLS)

This study examined the effects of pictorial motion cues and lateral organization in artworks on postural stability. Body sway of adults was measured as they viewed two paintings by Monet projected in their artist-created, original and reversed, mirror-image views. The paintings were comparable in terms of pictorial content, color, image size and o...

Performance of the vestibular, visual, and somatosensory systems decreases with age, reducing the capacity of postural control, and increasing the risk of falling. The purpose of this study is to measure the effects of vision, active vergence eye movements, viewing distance/vergence angle and a simple cognitive task on postural control during an up...

Introduction L’objectif etait d’investiguer l’effet de la reeducation de la vergence sur le controle postural chez des sujets avec un trouble isole de la vergence. Materiel et methode La vergence de 23 sujets (âge moyen ± SD = 23,1 ± 2 ans) a ete mesuree par video-oculographie (Eye SeeCam). Un bilan orthoptique et une evaluation de symptomatologie...

Contexte et objectifs : L’objectif est de voir si la présence d’Epines Irritatives d’Appui Planaire (EIAP) peut expliquer les idiosyncrasies observées dans l’étude précédente. Celle-ci avait montré que des stimulations plantaires fines améliorent le contrôle postural lors de mouvements des yeux. Nous supposons que les sujets porteurs d’EIAP sont pl...

Vertical heterophoria (VH) is the latent vertical misalignment of the eyes when the retinal images are dissociated, vertical orthophoria (VO) when there is no misalignment. Studies on postural control, during binocular vision in upright stance, reported that healthy subjects with small VH vs. VO are less stable, but the experimental cancellation of...

Op Art generates illusory visual motion. It has been proposed that eye movements participate in such illusion. This study examined the effect of eye movement instructions (fixation vs. free exploration) on the sensation of motion as well as the body sway of subjects viewing Op Art paintings. Twenty-eight healthy adults in orthostatic stance were su...

En prolongeant leur réflexion sur la posturographie appliquée à l’esthétique empirique, Kapoula et collègues s’interrogent sur la manière dont les évaluations émotionnelles (potentiellement distinctives) attribuées à trois versions numériquement modifiées du tableau « Nouvelle Neige sur l’Avenue » d’Edvard Munch (1906) influent sur le contrôle post...

Body sway while maintaining an upright quiet stance reflects an active process of balance based on the integration of visual, vestibular, somatosensory, and proprioceptive inputs. Richard Serra’s Promenade sculpture featured in the 2008 Monumenta exhibition at the Grand Palais in Paris, France is herein hypothesized to have stimulated the body’s ve...

Introduction L’objectif est d’évaluer l’effet de stimulations plantaires fines sur le contrôle postural lors de mouvements de vergence. Matériel et méthode La stabilité de 36 sujets asymptomatiques (25,7 ± 3,6 ans) a été enregistrée sur plateforme de forces selon 3 conditions: sans stimulation plantaire, avec un insert de 3mm d’épaisseur, média...

Purpose: While the overall development of saccades in children has recently gained increasing interest, the precise characteristics of vertical saccades remain understudied. This study focuses on the development of vertical saccades and their interaction with vergence movements. Methods: Thirty-one children (mean age 7.33 ± 0.21 years) performed ve...

La vergence oculaire active améliore la stabilité posturale ; la vergence fonctionne en synergie avec l’accommodation. Ici, nous étudions le développement chez l’enfant de la synergie vergence-accommodation et du contrôle postural.

Chez l’enfant dyslexique (Kapoula et Bucci 2007), ainsi que chez l’enfant strabique (Gaertner et al., 2013), l’exécution de mouvements actifs de vergence entre une cible proche et une lointaine améliore la stabilité posturale. Cette étude développementale explore l’effet de la vergence sur la stabilité posturale chez des enfants de 6 à 17 ans prése...

Les piercings, de plus en plus répandus, peuvent induire diverses complications, infectieuses, allergiques, cutanées ou dentaires… L’hétérophorie verticale (HV) et l’orthophorie correspondent, respectivement, à la présence ou l’absence de déviation verticale entre les deux yeux lorsque les images rétiniennes sont dissociées. Le présent rapport de c...

The invention relates to a device for rehabilitating and/or causing binocular motivity through sensory stimulation of a patient, said device including a planar stand (10) that is defined by a longitudinal axis of symmetry (AA′), the stand (10) including a plurality of means for transmitting at least one sensory stimulus, said transmission means inc...

Vergence insufficiency is an extraocular dysfunction screened regularly by ophthalmologists and orthoptists. Incidence increases with screen and computer work, resulting in visual quality and quality of life loss. Clinical diagnosis is based on associated well-defined criteria (Alvarez 2010, Horwood 2014). Quantification of symptoms reported (Echel...

By dissociating retinal images, an orthophoria and vertical heterophoria (VO and VH) correspond respectively to the absence or presence of a deviation in the vertical visual axis, deviation that is relieved in binocular vision. A physiological visual heterophoria exists; when induced experimentally, it influences postural control. The aim of this s...

Under natural circumstances, saccade-vergence eye movements are among the most frequently occurring. This study examines the properties of such movements focusing on short-term repetition effects. Are such movements robust over time or are they subject to tiredness? 12 healthy adults performed convergent and divergent combined eye movements either...

Clinical trials have shown the relationship between vertical heterophoria (VH), chronic pain and quality of postural control. The aim of this study was to simulate a vertical heterophoria and observe its influence on postural stability while in the upright stance. Fifteen healthy, young, normophoric adults (25.6 ± 3 yrs) without otoneurological or...

Romberg's test usually shows a stabilizing effect with eyes open than with eyes closed. Romberg's quotient (RQ) is generally 2.5. We examined the role of the converging angle on the quotient. We measured postural stability using a posture graphic platform in 18 young adults (mean age 25.3) and 17 elderly patients (mean age 61.6). They were instruct...

During visual fixation, the eyes are never completely still, but produce small involuntary movements, called "fixational eye movements," including microsaccades, drift, and tremor. In certain neurological disorders, attempted fixation results in abnormal fixational eye movements with distinctive characteristics. Thus, determining how normal fixatio...

There is a natural symbiosis between vergence and vestibular responses. Deficits in vergence can lead to vertigo, disequilibrium, and postural instability. This study examines both vergence eye movements in patients with idiopathic bilateral vestibular loss, and their standing balance in relation to vergence. Eleven patients participated in the stu...

This study focuses on 34 victims of aggression at the workplace, less than 48 hours following the incident of aggression. We compared victims who received an EMDR emergency protocol (URG-EMDR; n = 19) that we developed with those who received a method of intervention called eclectic therapy (n = 15). The results show that URG-EMDR therapy, provided...

We hypothesize that the high quality of binocular coordination of saccades in reading is progressively learned during childhood, and this oculomotor learning is based on a synergy between saccades and vergence. In present work deficits in the binocular control of saccades in six dyslexic children (mean age was 11±2.48 years) are studied for two tas...

VISION IS IMPORTANT FOR POSTURAL CONTROL AS IS SHOWN BY THE ROMBERG QUOTIENT (RQ): with eyes closed, postural instability increases relative to eyes open (RQ = 2). Yet while fixating at far distance, postural stability is similar with eyes open and eyes closed (RQ = 1). Postural stability can be better with both eyes viewing than one eye, but such...

Subjective tinnitus (ST) is a frequent but poorly understood medical condition. Recent studies demonstrated abnormalities in several types of eye movements (smooth pursuit, optokinetic nystagmus, fixation, and vergence) in ST patients. The present study investigates horizontal and vertical saccades in patients with tinnitus lateralized predominantl...

Purpose: In healthy subjects, the postural stability in orthostatic position is better when fixating at near than at far. Increase in the convergence angle contributes to this effect. Children with strabismus present a deficit in vergence. We evaluated postural control in children with respect to the vergence angle as they fixated at different dep...

There is controversy as to whether dyslexic children present systematic postural deficiency. Clinicians use a combination of ophthalmic prisms and proprioceptive soles to improve postural performances. This study examines the effects of convergent prisms and spherical lenses on posture. Fourteen dyslexics (13-17 years-old) and 11 non dyslexics (13-...

Purpose In healthy subjects, the postural stability in orthostatic position is better when fixating at near than at far distance; increased convergence angle contributes to such effect. Children with strabismus present a deficit in vergence movements. The goal of this study was to evaluate the postural control in children in relation with the verge...

Rapid, accurate and well coordinated saccades of the two eyes are a prerequisite for clear vision particularly during reading. The Iris group has studied fixation stability and saccadic parameters in good and bad readers. Specific impairments in these are found in dyslexic children, namely fixation instability due to disconjugate drifts, reduced bi...

This paper presents a novel modeling approach for dyslexic oculomotor control, called AFCMAC, an Auto-adaptive Fuzzy CMAC (Cerebellar Model Articulation Controller). We made some comparisons between the AFCMAC and the CMAC, over the standard deviation of binocular fixation disparity of ten dyslexic subjects while reading, in two viewing distances (...

This paper presents AFCMAC, an Auto-adaptive Fuzzy Cerebellar Model Articulation Controller, and its comparison with the traditional CMAC (Cerebellar Model Articulation Controller) for horizontal voluntary eye movements. We evaluated the performance of the AFCMAC and the traditional CMAC, by using the standard deviation of binocular fixation dispar...