Eye Movement Analysis Research Articles

The Analysis of Accommodation Response and Convergence Eye Movement When Viewing 8K Images

The Analysis of Accommodation Response and Convergence Eye Movement When Viewing 8K Images

Differential diagnosis of vergence and saccade disorders in dyslexia

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 spectacles). Other studies have identified deficits with binocular coordination during reading in dyslexics. Yet, there are few studies that provide objective measurements of eye movements in the dyslexic population to help provide more information regarding if these deficits could be due to an intrinsic motor problem or if they are the consequence of poor reading. 47 dyslexic adolescents (18 female, 29 male; mean age 15.5) and 44 non-dyslexic adolescents (22 female, 22 male; mean age 14.8) wore a head-based eye tracker (PupilCore, Pupil Labs, Berlin) which recorded wide angle saccade and vergence eye movements at 200 Hz. Tests were run using the REMOBI device, which produced a saccade or vergence audiovisual target. Analysis of eye movements was performed with lab-developed software, AIDEAL. The results showed statistically significant abnormalities in vergence and saccades. In vergence, dyslexics displayed a reduced amplitude of the visually driven portion of convergence and a longer duration in the initial phase of divergence. In saccades, dyslexic adolescents demonstrated slower saccades in both directions. They also had an increased disconjugate drift in the first 80 or 160 ms following saccades to the right, suggesting poor binocular coordination. For both vergence and saccades, the peak velocity and time to peak velocity was higher and earlier, respectively, in non-dyslexics compared to dyslexics; yet the average velocity of both movements was lower in dyslexics. Thus, these results indicate peculiar velocity profiles in dyslexics, particularly a slow deceleration phase in both vergence and saccades. The study provides an objective method to diagnose vergence and saccade abnormalities while viewing targets in the real three-dimensional space in a dyslexic population. Vergence abnormalities are demonstrated to be a problem in dyslexics, occurring independently from reading. We hypothesize these disconjugate drifts following saccades are the result of slow vergence capacity. Rehabilitation programs, such as those using REMOBI, should aim to target these deficits in vergence velocity, as this has been shown to improve binocular control.

Virtual reality–based mindfulness training, sensory activation and mental assessment in dementia care

AbstractBackgroundRecent studies underline the importance of cognitive reserve, which is supported by stress reduction, pleasure experience and meditation, for mental health. Mindfulness training is successfully applied to dementia and indicate a lasting positive effect on cognitive reserve, well‐being and motivation. The research project OpenSense investigated the potential of VR‐based intervention and assessment for dementia care in a proof‐of concept study. The VR‐based intervention was developed to foster mindfulness and sensory activation.MethodVR‐based intervention was applied in persons with dementia (PwD) with Alzheimer’s dementia (AD; n=12, age M=85.0 years, MMSE M=21.5) and healthy controls (n=12, age M=75.1 years, MMSE M=30) using 30 minutes of panoramic video‐based multi‐sensory experiences presenting stimuli that empower relaxation (body‐scanning, beach, forest) and activation (bakery, orchestra). EEG‐based alpha‐band signals (8‐12 Hz) associated with relaxation and inhibitory control were recorded before, during and after intervention and eye tracking was applied during intervention.ResultPre‐post EEG analysis showed significant increases in alpha power and brain connectivity for PwD with AD and controls (post > pre, p<.05). EEG baseline alpha power demonstrated higher values for healthy controls than for PwD (AD). Eye movement analysis demonstrated significant differences between PwD (AD) and controls: eye blink rate AD > controls, p=.004(**) from the observation of a 3 minutes video, and significant correlation (Rho=.607, p=.003(**); 3 minutes video) was achieved between eye movements and the Freiburg Mindfulness Inventory score.ConclusionThe potential of VR‐based intervention based on mindfulness and sensory activation is very promising: the study demonstrated significant increases of EEG alpha power and brain connectivity where PwD usually suffer from decline and gaze data acquired during intervention indicate potential for non‐invasive assessment for decision support. OpenSense anticipates numerous opportunities for novel VR‐based care services for empowering cognitive reserve, inducing sensory activation, raising awareness and motivation for self‐regulation, and as pervasive assessment tool.

Deep-learning-based reading eye-movement analysis for aiding biometric recognition

Eye-movement recognition is a new type of biometric recognition technology. Without considering the characteristics of the stimuli, the existing eye-movement recognition technology is based on eye-movement trajectory similarity measurements and uses more eye-movement features. Related studies on reading psychology have shown that when reading text, human eye-movements are different between individuals yet stable for a given individual. This paper proposes a type of technology for aiding biometric recognition based on reading eye-movement. By introducing a deep-learning framework, a computational model for reading eye-movement recognition (REMR) was constructed. The model takes the text, fixation, and text-based linguistic feature sequences as inputs and identifies a human subject by measuring the similarity distance between the predicted fixation sequence and the actual one (to be identified). The experimental results show that the fixation sequence similarity recognition algorithm obtained an equal error rate of 19.4% on the test set, and the model obtained an 86.5% Rank-1 recognition rate on the test set.

An Analysis of Eye-Tracking Features and Modelling Methods for Free-Viewed Standard Stimulus: Application for Schizophrenia Detection.

Currently psychiatry is a medical field lacking an automated diagnostic process. The presence of a mental disorder is established by observing its typical symptoms. Eye-movement specifics have already been established as an "endophenotype" for schizophrenia, but an automated diagnostic process of eye-movement analysis is still lacking. This article presents several novel approaches for the automatic detection of a schizophrenic disorder based on a free-view image test using a Rorschach inkblot and an eye tracker. Several features that enabled us to analyse the eye-tracker signal as a whole as well as its specific parts were tested. The variety of features spans global (heat maps, gaze plots), sequences of features (means, variances, and spectra), static (x and y signals as 2D images), dynamic (velocities), and model-based (limiting probabilities and transition matrices) categories. For each set of features, a proper modelling and classification method was designed (convolutional, recurrent, fully connected and combined neural networks; Hidden Markov models). By doing so, it was possible to find the importance of each feature and its physical representation using k-fold cross validation and a paired t-test. The dataset was sampled on 22 people with schizophrenia and 22 healthy individuals. The most successful approach was based on heat maps using all data and convolutional networks, reaching a 78.8% accuracy, which is a 10.5% improvement over the reference method. From all tested methods, there are two in an 85% accuracy range and over fifteen others in a 75% accuracy range at a 10% significance level.

Decision-making and dynamics of eye movements in volleyball experts

Key decision-makers among experts in a given field can sometimes be identified based on their role and responsibilities. The aim of the study is to compare perceptual-cognitive skills of experts with decisional responsibilities (setters in volleyball) with that of other volleyball experts. Eighty-two participants (26 setters, 36 other players and 20 controls) viewed 50 volleyball video sequences. Sequences stopped 120 ms before ball contact and participants, whose eye movements were recorded, had to predict the ball direction. Generalized Estimating Equations analysis revealed that setters and controls made more but shorter fixations than other players. However, both expert groups made better predictions than controls. Dynamics analyses of eye movements over time show that, right before ball contact, opposing players’ upper body is a most relevant attentional cue in all game situations. Results are discussed in terms of decision-making responsibilities to identify key decision-makers in volleyball and in general. They point towards specific perceptual-cognitive abilities found in setters and support the idea that they constitute a subgroup of experts, but that they are not “better” than other players in anticipating the game.

Chinese college students' ability to recognize facial expressions based on their meaning-in-life profiles: An eye-tracking study.

People can be categorized into one of four meaning-in-life profiles: High Presence High Search (HPHS), High Presence Low Search (HPLS), Low Presence High Search (LPHS), and Low Presence Low Search (LPLS).The main goal of this study is to provide a theoretical explanation for why Chinese people with different meaning-in-life profiles have different mental health levels than Western people, based on their emotional-cognitive-processing ability. We adopted eye-movement analysis and recognition-judgment experimental paradigm concerning absolute-recognition judgment and relative-recognition judgment in our study. Moreover, we applied a multifactor and multilevel mixed-experimental design. We selected 118 participants for the experiments from the 788 Chinese college students who responded. Our results showed that HPHS individuals preferred positive-emotion pictures, LPLS individuals preferred negative-emotion pictures, HPLS individuals preferred positive- and neutral-emotion pictures, and LPHS individuals preferred neutral-emotion pictures. Moreover, HPHS individuals were better at accurately processing facial expression from pictures, while LPLS individuals lacked such ability. The fine-processing ability of HPLS and LPHS individuals was lower than that of HPHS yet higher than that of LPLS individuals. Moreover, the features of HPLS individuals were closer to HPHS, while those of LPHS individuals were closer to LPLS. Our findings support the hypothesis that meaning-in-life profiles have different immediate processing abilities and preferences regarding facial expression recognition and different emotional-cognitive-processing ability.

Clinical application of 3D-VOG analysis for quantitative evaluation of Otolith-Ocular reflex in the roll and pitch planes

Background Management of vestibular falls requires precise evaluation of otolithic function and gravity recognition. Tilt of the head in the roll plane causes ocular counter rolling (OCR) with a gain of 5–10%, which can be a quantitative parameter related to the otolith-ocular reflex (OOR) in that plane. However, the OOR in the pitch plane is indiscernible because of our ability to voluntarily gaze and pursue. 3 D eye movements and its Listing’s plane description can provide novel parameters with which to evaluate OOR, even in the pitch plane. Objectives To evaluate the utility of 3 D eye movement analysis in video oculography (VOG) as a quantitative parameter reflecting otolithic function during head movements associated with daily life. Materials and methods In healthy subjects, we analyzed the changes in 3 D eye movements and the Listing’s plane that occur with static gravitational modification. Results OOR during head tilt in the roll plane revealed that OCR amplitude had a saturating/peaked conformation and was not fitted by a sine curve. OOR in the pitch plane revealed anteroposterior leaning of the Listing’s plane. Conclusions These novel tools for minimally invasive evaluation of OOR in a clinical setting could potentially enable us to quantitatively evaluate peripheral static disequilibrium.

Task demands modulate the effects of speech on text processing.

Task-irrelevant background sound can disrupt performance of visually based cognitive tasks. The cross-modal breakdown of attentional selectivity in the context of reading was addressed using analyses of eye movements. Moreover, the study addressed whether task-sensitivity to distraction via background speech on reading was modulated by the cognitive demands of the focal task. Two randomly-assigned groups of native Chinese participants read the same set of Chinese experimental sentences while being exposed to meaningful speech, meaningless (foreign) speech, or silence. For one group, participants were instructed to judge whether the sentences made sense (i.e., semantic acceptability task); for another, participants were instructed to detect whether the sentences contained a noncharacter (i.e., noncharacter detection task). Results showed no significant effect across sound conditions for the noncharacter detection task. For the semantic acceptability task, however, there was a substantial disruptive effect of the meaningfulness of the speech. Compared with reading with meaningless speech or reading in silence, the meaningful speech increased numbers of fixations, regressions, regression path, and total reading times. These results suggest that the disruption of reading by background speech is jointly dependent on the nature of the speech and the task process deployed, thereby favoring an Interference-by-Process account over Interference-by-Content and Attentional Diversion accounts of distraction to reading by background sound. (PsycInfo Database Record (c) 2020 APA, all rights reserved).

Looking with the (computer) mouse: How to unveil problem-solving strategies in matrix reasoning without eye-tracking.

Problem-solving strategies in visual reasoning tasks are often studied based on the analysis of eye movements, which yields high-quality data but is costly and difficult to implement on a large scale. We devised a new graphical user interface for matrix reasoning tasks where the analysis of computer mouse movements makes it possible to investigate item exploration and, in turn, problem-solving strategies. While relying on the same active perception principles underlying eye-tracking (ET) research, this approach has the additional advantages of being user-friendly and easy to implement in real-world testing conditions, and records only voluntary decisions. A pilot study confirmed that embedding items of Raven's Advanced Progressive Matrices (APM) in the interface did not significantly alter its psychometric properties. Experiment 1 indicated that mouse-based exploration indices, when used to assess two major problem-solving strategies in the APM, are related to final performance-as has been found in past ET research. Experiment 2 suggested that constraining some features of the interface favored the adoption of the more efficient solving strategy for some participants. Overall, the findings support the relevance of the present methodology for accessing and manipulating problem-solving strategies.

Recognizing Decision-Making Using Eye Movement: A Case Study With Children.

The use of visual attention for evaluating consumer behavior has become a relevant field in recent years, allowing researchers to understand the decision-making processes beyond classical self-reports. In our research, we focused on using eye-tracking as a method to understand consumer preferences in children. Twenty-eight subjects with ages between 7 and 12 years participated in the experiment. Participants were involved in two consecutive phases. The initial phase consisted of the visualization of a set of stimuli for decision-making in an eight-position layout called Alternative Forced-choice. Then the subjects were asked to freely analyze the set of stimuli, they needed to choose the best in terms of preference. The sample was randomly divided into two groups balanced by gender. One group visualized a set of icons and the other a set of toys. The final phase was an independent assessment of each stimulus viewed in the initial phase in terms of liking/disliking using a 7-point Likert scale. Sixty-four stimuli were designed for each of the groups. The visual attention was measured using a non-obstructive eye-tracking device. The results revealed two novel insights. Firstly, the time of fixation during the last four visits to each stimulus before the decision-making instant allows us to recognize the icon or toy chosen from the eight alternatives with a 71.2 and 67.2% of accuracy, respectively. The result supports the use of visual attention measurements as an implicit tool to analyze decision-making and preferences in children. Secondly, eye movement and the choice of liking/disliking choice are influenced by stimuli design dimensions. The icon observation results revealed how gender samples have different fixation and different visit times which depend on stimuli design dimension. The toy observations results revealed how the materials determinate the largest amount fixations, also, the visit times were differentiated by gender. This research presents a relevant empirical data to understand the decision-making phenomenon by analyzing eye movement behavior. The presented method can be applied to recognize the choice likelihood between several alternatives. Finally, children’s opinions represent an extra difficulty judgment to be determined, and the eye-tracking technique seen as an implicit measure to tackle it.

Orthographic learning of novel words in adults: effects of exposure and visual attention on eye movements

ABSTRACT Eye movement monitoring was used to explore the time course of orthographic learning in adult skilled readers while they read novel words presented in isolation one, three or five times. Offline measures of spelling-to-dictation and orthographic decision were used to measure orthographic memorisation. Further, the participants' visual attention span was estimated. Results showed better memorisation of new words' orthography with additional exposures. An exposure-by-exposure in-depth analysis of eye movements revealed an early sharper decrease for the number of fixations and most measures of processing time. Participants with a higher visual attention span showed better performance in orthographic decision and processing times. The overall findings suggest that orthographic learning occurs from the first exposure and that top-down effects from the newly acquired orthographic knowledge would facilitate processing from the second exposure. Further, time needed for bottom-up information extraction appears to be modulated by visual attention span.

Eye Movements of Spatial Working Memory Encoding in Children with and without Autism: Chunking Processing and Reference Preference.

Individuals with autism spectrum disorder (ASD) experience spatial working memory deficits and show different encoding mechanisms from typical developing (TD) peers. To effectively describe the encoding strategies of those with ASD and highlight their characteristics in cognitive processing, we adopted improved change detection tasks and added eye-movement indicators to investigate the chunking function and reference preference of children with and without ASD. The current study included 20 participants with ASD aged 8-16 and 20 TD children matched for age, gender, and intelligence. Experiment 1 used high/low-structured change detection tasks, and eye-movement indexes were recorded as they memorized the locations of the items to investigate spatial chunking strategies. In Experiment 2, changes in eye movement patterns were observed by adding a frame of reference. The results suggested different encoding strategies in ASD and TD individuals. The ASD group showed local processing bias and had difficulty adopting chunking strategies in spatial working memory. Eye-movement analysis suggested that they rarely showed integrated information processing tendency observed in TD children. Moreover, as a compensatory processing, they were more likely to use the frame of reference. In this study, we compared the spatial chunking strategies and reference preference of children with and without ASD, and eye-movement analysis was used to investigate the processing mechanism. These findings are significant for research on cognitive characteristics of ASD and provide a new focus for working memory training in children with ASD. LAY SUMMARY: The current study suggests that children with autism spectrum disorder are poorer at organizing items into chunks in spatial working memory, but rely more on reference frames. If the purpose of location memory is to strengthen the adaptability of children with autism, it should provide them with more clues or references. If it is for the purpose of intervention such as cognitive training, it should guide them to integrate information to improve the basic cognitive processing efficiency. Autism Res 2021, 14: 897-910. © 2020 International Society for Autism Research and Wiley Periodicals LLC.

Comparing neurotypical adults differing in their position on the autism spectrum - a qualitative analysis of eye movements

Comparing neurotypical adults differing in their position on the autism spectrum - a qualitative analysis of eye movements

Positional Change of the Eyeball During Eye Movements: Evidence of Translatory Movement.

Purpose: To investigate the positional change of the eyeball induced by horizontal and vertical gazing to deduce translatory movement, using three-dimensional (3D) magnetic resonance imaging (MRI).Methods: In this prospective observational study participants underwent orbital MRI during central, right, left, up, and down gazing. MRI scans were processed using self-developed software; this software enabled 3D MR image reconstruction and the superimposition of reconstructed image sets between different gazes. After acquiring the coordinates of the eyeball centroid in each gaze, the changes in centroid coordinates from central gaze to the other gazes were estimated, and correlations with associated factors were evaluated.Results: The mean distance of centroid movement was 0.69 ± 0.27 mm in abduction, 0.68 ± 0.27 mm in adduction, 0.43 ± 0.23 mm in elevation, and 0.44 ± 0.19 mm in depression. The mean angle of centroid movement in horizontal gaze, measured in terms of the movement of the left eye centroid in the axial plane, was 228.7° in abduction and −4.2° in adduction. In vertical gaze, the mean angle of centroid movement was −96.8° in elevation and 101.8° in depression. Axial length and ocular volume were negatively correlated with the distance of centroid movement in horizontal gaze.Conclusions: The position of the eyeball moved in the same direction as the gaze during horizontal gaze, but in the opposite direction during vertical gaze. For accurate eye movement analyses, such as the measurement of the deviation angle in strabismus, translation should be considered in addition to rotation.

The interrelation between interpretation biases, threat expectancies and pain-related attentional processing.

Few studies examining the effect of pain-related threat on eye movements have incorporated a measure of interpretation bias. However, theories suggest that interpretation biases also play an important role in the anticipation of harm in situations where pain could be imminent. The current study investigates the association between interpretation biases and pain-related threat expectancies and their associations with eye movements to pain-related imagery. Healthy adults' (N=91) fear of pain, emotional functioning and interpretation biases were assessed prior to a threat manipulation where they were given either threatening or reassuring information about an upcoming cold pressor task. Participants were then asked to freely view scene images that were either pain-related or neutral. We used a data-driven machine learning method to analyse eye movements. We identified an explorative (i.e. greater dispersal of eye fixations) and a focused eye movement pattern subgroup (i.e. mainly focusing on foreground information) for scene viewing in the sample. Participants with more negative interpretation biases expected that the cold pressor task would be more harmful, and those with higher levels of anticipated harm used a more explorative strategy when viewing injury scene images. Subsequent analysis confirmed an indirect effect of interpretation biases on eye movements through expected bodily harm. No difference in eye movements was found between participants given threatening and reassuring information. Interpretation biases may play a prominent role in threat-related attentional processing. By adopting a novel eye movement analysis approach, our results revealed interesting associations among interpretations, threat expectancies and eye movements. Negative interpretation biases may be associated with greater threat expectancies for an upcoming experimental pain task. Anticipation of bodily harm may induce a stimulus non-specific hypervigilant style of scanning of pain-related scenes.

Pseudo-colouring an ECG enables lay people to detect QT-interval prolongation regardless of heart rate.

Drug-induced long QT syndrome (diLQTS), characterized by a prolongation of the QT-interval on the electrocardiogram (ECG), is a serious adverse drug reaction that can cause the life-threatening arrhythmia Torsade de Points (TdP). Self-monitoring for diLQTS could therefore save lives, but detecting it on the ECG is difficult, particularly at high and low heart rates. In this paper, we evaluate whether using a pseudo-colouring visualisation technique and changing the coordinate system (Cartesian vs. Polar) can support lay people in identifying QT-prolongation at varying heart rates. Four visualisation techniques were evaluated using a counterbalanced repeated measures design including Cartesian no-colouring, Cartesian pseudo-colouring, Polar no-colouring and Polar pseudo-colouring. We used a multi-reader, multi-case (MRMC) receiver operating characteristic (ROC) study design within a psychophysical paradigm, along with eye-tracking technology. Forty-three lay participants read forty ECGs (TdP risk n = 20, no risk n = 20), classifying each QT-interval as normal/abnormal, and rating their confidence on a 6-point scale. The results show that introducing pseudo-colouring to the ECG significantly increased accurate detection of QT-interval prolongation regardless of heart rate, T-wave morphology and coordinate system. Pseudo-colour also helped to reduce reaction times and increased satisfaction when reading the ECGs. Eye movement analysis indicated that pseudo-colour helped to focus visual attention on the areas of the ECG crucial to detecting QT-prolongation. The study indicates that pseudo-colouring enables lay people to visually identify drug-induced QT-prolongation regardless of heart rate, with implications for the more rapid identification and management of diLQTS.

Disease Classification Based on Eye Movement Features With Decision Tree and Random Forest.

Medical research shows that eye movement disorders are related to many kinds of neurological diseases. Eye movement characteristics can be used as biomarkers of Parkinson’s disease, Alzheimer’s disease (AD), schizophrenia, and other diseases. However, due to the unknown medical mechanism of some diseases, it is difficult to establish an intuitive correspondence between eye movement characteristics and diseases. In this paper, we propose a disease classification method based on decision tree and random forest (RF). First, a variety of experimental schemes are designed to obtain eye movement images, and information such as pupil position and area is extracted as original features. Second, with the original features as training samples, the long short-term memory (LSTM) network is used to build classifiers, and the classification results of the samples are regarded as the evolutionary features. After that, multiple decision trees are built according to the C4.5 rules based on the evolutionary features. Finally, a RF is constructed with these decision trees, and the results of disease classification are determined by voting. Experiments show that the RF method has good robustness and its classification accuracy is significantly better than the performance of previous classifiers. This study shows that the application of advanced artificial intelligence (AI) technology in the pathological analysis of eye movement has obvious advantages and good prospects.

New Category III Code: Eye Movement Analysis

Category III (new or emerging technology) code 0615T was implemented on July 1, 2020 (prior to inclusion in CPT 2021) for reporting eye movement testing in patients who have a head injury that may be a traumatic brain injury or concussion.

Human video database for facial feature detection under spectacles with varying alertness levels: a baseline study

The pressing demand for workload along with social media interaction leads to diminished alertness during work hours. Researchers attempted to measure alertness level from various cues like EEG, EOG, video-based eye movement analysis, etc. Among these, video-based eyelid and iris motion tracking gained much attention in recent years. However, most of these implementations are tested on video data of subjects without spectacles. These videos do not pose a challenge for eye detection and tracking. In this work, the authors have designed an experiment to yield a video database of 58 human subjects wearing spectacles and are at different levels of alertness. Along with spectacles, they introduced variation in session, recording frame rate (fps), illumination, and time of the experiment. They carried out an analysis to detect the reliableness of facial and ocular features like yawning and eye-blinks in the context of alertness level detection capability. Also, they observe the influence of spectacles on ocular feature detection performance under spectacles and propose a simple preprocessing step to alleviate the specular reflection problem. Extensive experiments on real-world images demonstrate that the authors’ approach achieves desirable reflection suppression results within minimum execution time compared to the state-of-the-art.