Eye Tracking Performance Research Articles

Evaluation of Saccadic Component Measure on Smooth Pursuit Tests.

Despite the advancement of eye-tracking technology for smooth pursuit (SP) eye movement evaluation, qualitative observation offers much information that is not captured by computers; hence, both objective and qualitative information should be utilized to evaluate SP. This study examined the consistency among our clinicians when evaluating SP using normal (N), grossly normal (GN), mildly abnormal (MA), and abnormal (AB) as classifications. We then evaluated the effect of combining GN and MA into a single subclinical (SUBC) category. We also evaluated the computerized percent saccade (PS) metric by determining its sensitivity and specificity in classifying SP. Retrospective horizontal and vertical SP test videos and numerical data for 70 participants were obtained from the Neuro Kinetics Neuro-Otologic Test Center and de-identified. From this, eye-tracking videos, time plots of eye-tracking positional data, and tables of SP eye-tracking performance data were generated for 0.1, 0.3, and 0.5 Hz in both horizontal and vertical planes, totaling 6 tests per subject. Three clinicians rated each subject's SP performance as N, GN, MA, or AB for a total of 6 ratings (3 frequencies, horizontal and vertical). This process was repeated using N, SUBC, and AB as rating categories. Clinicians also provided an overall SP rating for each plane as follows: AB if the results were abnormal for 2 or more frequencies tested. Alternatively, if fewer than 2 frequencies presented with a rating of AB, then an overall rating of MA, GN, or N was determined at the respective clinician's discretion. When the 3 clinicians were tasked with classifying SP videos using 4 clinical categories, fair overall agreement was demonstrated. However, when MA and GN categories were combined into an SUBC category, the overall agreement for the 3 clinicians improved slightly for both horizontal SP (HSP) and vertical SP (VSP). This pattern of agreement did not differ considerably when comparing HSP versus VSP, and good consistency and reliability was observed across clinicians. Again, inter-rater consistency was smaller for VSP versus HSP despite the reduction in clinical categories. Cut-off values were generated for the PS metric and demonstrated good specificity and sensitivity when they were exceeded for 2 or more frequencies in a particular plane when evaluating a subject's SP test.

Examining Eye Tracking Metrics and Cognitive Function in Post-Stroke Individuals: A Comparison of Visual Searching Tasks between Those with and without Cognitive Impairment

Introduction: After a stroke, individuals commonly experience visual problems and impaired cognitive function, which can significantly impact their daily lives. In addition to visual neglect and hemianopia, stroke survivors often have difficulties with visual search tasks. Researchers are increasingly interested in using eye tracking technology to study cognitive processing and determine whether eye tracking metrics can be used to screen and assess cognitive impairment in patients with neurological disorders. As such, assessing these areas and understanding their relationship is crucial for effective stroke rehabilitation. Methods: We enrolled 60 stroke patients in this study and evaluated their eye tracking performance and cognitive function through a series of tests. Subsequently, we divided the subjects into two groups based on their scores on the HK-MoCA test, with scores below 21 out of 30 indicating cognitive impairment. We then compared the eye tracking metrics between the two groups and identified any significant differences that existed. Spearman correlation analysis was conducted to explore the relationship between clinical test scores and eye tracking metrics. Moreover, we employed a Mann-Whitney U test to compare eye tracking metrics between groups with and without cognitive impairment. Results: Our results revealed significant correlations between various eye tracking metrics and cognitive tests (p ≤ 0.001–0.041). Furthermore, the group without cognitive impairment demonstrated higher saccade velocity, gaze path velocity, and shorter time to target than the group with cognitive impairment (p ≤ 0.001–0.040). Receiver operating characteristic curve analyses were performed, and the optimal cut-off values for gaze path velocity and saccade velocity were 329.665 (px/s) (sensitivity = 0.80, specificity = 0.533) and 2.150 (px/ms) (sensitivity = 0.733, specificity = 0.633), respectively. Conclusions: Our findings indicate a significant correlation between eye tracking metrics and cognitive test scores. Furthermore, the group with cognitive impairment exhibited a significant difference in these metrics, and a cut-off value was identified to predict whether a client was experiencing cognitive impairment.

Brain computed tomography reading of stroke patients by resident doctors from different medical specialities: An eye-tracking study

BackgroundUsing the eye-tracking technique, our work aimed to examine whether difference in clinical background may affect the training outcome of resident doctors’ interpretation skills and reading behaviour related to brain computed tomography (CT). MethodsTwelve resident doctors in the neurology, radiology, and emergency departments were recruited. Each participant had to read CT images of the brain for two cases. We evaluated each participant’s accuracy of lesion identification. We also used the eye-tracking technique to assess reading behaviour. We recorded dwell times, fixation counts, run counts, and first-run dwell times of target lesions to evaluate visual attention. Transition entropy was applied to assess the temporal relations and spatial dynamics of systematic image reading. ResultsThe eye-tracking results showed that the image reading sequence examined by transition entropy was comparable among resident doctors from different medical specialties (p = 0.82). However, the dwell time of the target lesions was shorter for the resident doctors from the neurology department (4828.63 ms, p = 0.01) than for those from the resident doctors from the radiology (6275.88 ms) and emergency (5305.00 ms) departments. The eye-tracking results in individual areas of interest only showed differences in the eye-tracking performance of the first-run dwell time (p = 0.05) in the anterior cerebral falx. DiscussionOur findings demonstrate that resident doctors from different medical specialties may achieve similar imaging reading patterns for brain CT. This may mitigate queries regarding the influence of different backgrounds on training outcomes.

Visual Analysis of Panoramic Radiographs among Pediatric Dental Residents Using Eye-Tracking Technology: A Cross-Sectional Study.

The aim of this cross-sectional study was to explore the eye tracking (ET) performance of postgraduate pediatric dental students in correctly detecting abnormalities in different sets of panoramic radiographs. This observational study recruited postgraduate pediatric dental students to evaluate seven panoramic radiographs. RED-m® SMI software (Sensomotoric Instruments, Teltow, Germany) was used to track the participants' eye movements as they looked at the radiographs. The data collected for areas of interest (AOIs) included revisit counts, fixation counts, fixation times, entry times, and dwell times. Univariate and bivariate analyses were conducted to summarize the participants' characteristics and ET measures. The overall percentage of correctly located AOIs was 71.7%. The residents had significantly more revisits and fixation counts in AOIs located in one sextant than in multiple sextants (p < 0.001). Similar patterns were observed for fixation and dwell times (p < 0.001), but not for entry time. Heatmaps showed that the highest density of fixations was on the AOIs and the residents fixated more on dentition than on bony structures. In single-sextant radiographs, residents had significantly more revisits and fixation counts for AOIs compared to those of multiple sextants. Residents had slower entry times and dwelled less on AOIs located in multiple sextant(s). The reported findings can direct dental educators to develop a standardized scan scheme of panoramic radiographs to minimize misdiagnosis.

Deep learning models for webcam eye tracking in online experiments

Eye tracking is prevalent in scientific and commercial applications. Recent computer vision and deep learning methods enable eye tracking with off-the-shelf webcams and reduce dependence on expensive, restrictive hardware. However, such deep learning methods have not yet been applied and evaluated for remote, online psychological experiments. In this study, we tackle critical challenges faced in remote eye tracking setups and systematically evaluate appearance-based deep learning methods of gaze tracking and blink detection. From their own homes and laptops, 65 participants performed a battery of eye tracking tasks including (i) fixation, (ii) zone classification, (iii) free viewing, (iv) smooth pursuit, and (v) blink detection. Webcam recordings of the participants performing these tasks were processed offline through appearance-based models of gaze and blink detection. The task battery required different eye movements that characterized gaze and blink prediction accuracy over a comprehensive list of measures. We find the best gaze accuracy to be 2.4° and precision of 0.47°, which outperforms previous online eye tracking studies and reduces the gap between laboratory-based and online eye tracking performance. We release the experiment template, recorded data, and analysis code with the motivation to escalate affordable, accessible, and scalable eye tracking that has the potential to accelerate research in the fields of psychological science, cognitive neuroscience, user experience design, and human–computer interfaces.

Moderate Severity SARS-CoV-2 (COVID-19) Affects Ocular Vergence Indices: Eye Tracking-Based Study.

Since the start of the SARS-CoV-2 (COVID-19) pandemic, it has become clear that the brain is one of the main targets for acute and chronic damage. Although neurodegenerative changes have yet to be investigated, there is already a large body of data on damage to its fiber tracts. A mobile eye tracker is possibly one of the best tools to study such damage in a COVID hospital setting. At the same time, the available data indicate that eye tracking parameters, even in healthy volunteers, demonstrate a distinct gender-specific difference.The aim of the work is to evaluate functional and structural impairments of the fiber tracts and to find possible gender-specific dynamics of eye tracking indicators in the acute period of COVID-19 pneumonia (Delta variant) of moderate severity. A single-center non-randomized retrospective study included 84 patients in the acute period of moderate severity SARS-CoV-2 (COVID-19) pneumonia (Delta variant) (Group 1). The mean time from admission was 1.4±1.2days. M:41, F:43. According to thoracic CT, the lung involvement ranged from CT 1 to CT 2. SpO2 ranged from 95% to 99%. The mean age was 35.5±14.8years (from 18 to 60). The control group (Group 2) included 158 healthy volunteers without pathology of the vision organs and central nervous system.The eye vergence index (VRx) was determined using eye tracking as a motion correlation coefficient between the angular velocities of the left and right eyeballs and was a measure of the conjugation of horizontal and vertical eye movements.The mobile complex Eye Tracker Low-Speed 20 (BVG LLC, the Netherlands) was used. Eye tracking parameters were assessed by vertical and horizontal eye vergence (VVRx and HVRx).Statistical analysis was done using the methods of parametric and non-parametric statistics. Moderate COVID-19 pneumonia resulted in a significant decrease in both VVRx and HVRx compared to controls (0.763±0.127 and 0.856±0.043; p<0.000001; 0.729±0.018 and 0.776±0.023 p<0.000001, respectively). VVRx values were significantly higher in men (0.775±0.046 and 0.747±0.091, p=0.019, respectively), while ХVRx values were significantly higher in women (0.665±0.018 and 0.728±0.024, p<0.0000001, respectively). SARS-CoV-2 (COVID-19) of moderate severity is accompanied by a significant deterioration in eye tracking performance proving functional and structural impairments (p<0.05). VVRx was significantly higher in men, and HVRx was substantially greater in women reflecting gender-specific differences.

Effects of tracker location on the accuracy and precision of the Gazepoint GP3 HD for spectacle wearers.

Remote view eye-tracking systems are prone to errors when used on spectacle wearers due to reflections from the lenses and frame that result in inaccurate tracking. Traditionally, these trackers are situated below a computer monitor and the viewer's eye moments are recorded while they view the screen. Reflections may be influenced by the pantoscopic tilt of the spectacles, whereby the tilt angle causes incident light to be reflected to the camera. To overcome this problem, we propose mounting the tracker above the monitor to avoid these reflections and test the accuracy and precision of subjects with single vision spectacles, multifocals, and no correction, using both mounting positions. Experimental results showed that this alternate position had overall worse accuracy (4.06° ± 0.13) and precision (0.67° ± 0.05) compared to the standard configuration (2.15° ± 0.06 vs. 0.50° ± 0.03), with more invalid readings (5.91 vs. 19.19%) for single vision lens wearers. Multifocals performed better for the top-mounting position for the top portion of the monitor, suggesting higher-order aberrations from the bottom portion of the lens negatively impact data quality. Higher pantoscopic tilt angles displayed an improved accuracy for this alternate position (r(9) = - 0.69, p = 0.02), with superior accuracy for tilt angles greater than 14° compared to the standard configuration. This study quantifies the impact of spectacle wear on eye-tracking performance and suggests other alternate mounting positions may be viable in certain situations.

Motion and viewing analysis during minimally invasive surgery for autostereoscopic visualization.

Autostereoscopic 3D visualization (ASV) forms a potentially appealing alternative to stereoscopic 3D displays to help surgeons regain depth perception during minimally invasive surgery (MIS). However, the feasibility of using single-viewer ASV has not yet been demonstrated in a clinical context. The purpose of the study is to analyze the current surgical workflow and display usage and assess the potential for using ASV in MIS applications. Additionally, the study seeks to acquire a better understanding of key design requirements, such as the eye-tracking performance and the lenticular lens 3D workspace. Two types of gynecologic interventions were investigated. A vision-based tracking system was developed, consisting of depth cameras mounted on the displays and ArUco markers placed on the hair caps of clinicians and the wall of the operating room. This allowed simultaneous tracking of the pose of operating staff and displays. Overall 20 surgeries were recorded, where 4 clinicians operated using 3 displays. Users were typically standing at a mean distance of 1900mm in a range from to 1200 to 2300mm from the display. Left-right motion was from -600 to 658mm. Clinicians stood on average 1000mm from each other. The head roll angle was below 16[Formula: see text]. Surgeons were looking predominantly (99%) to the same display. Observations took place from fairly well-defined places and with sufficient potential to differentiate between clinicians, suggesting that single-viewer ASV would be feasible.

Technostress causes cognitive overload in high-stress people: Eye tracking analysis in a virtual kiosk test

In the midst of the COVID-19 pandemic, the use of non-face-to-face information and communication technology (ICT) such as kiosks has increased. While kiosks are useful overall, those who do not adapt well to these technologies experience technostress. The two most serious technostressors are inclusion and overload issues, which indicate a sense of inferiority due to a perceived inability to use ICT well and a sense of being overwhelmed by too much information, respectively. This study investigated the different effects of hybrid technostress—induced by both inclusion and overload issues—on the cognitive load among low-stress and high-stress people when using kiosks to complete daily life tasks. We developed a ‘virtual kiosk test’ to evaluate participants’ cognitive load with eye tracking features and performance features when ordering burgers, sides, and drinks using the kiosk. Twelve low-stress participants and 13 high-stress participants performed the virtual kiosk test. As a result, regarding eye tracking features, high-stress participants generated a larger number of blinks, a longer scanpath length, a more distracted heatmap, and a more complex gaze plot than low-stress participants. Regarding performance features, high-stress participants took significantly longer to order and made more errors than low-stress participants. A support-vector machine (SVM) using both eye tracking features (i.e., number of blinks, scanpath length) and a performance feature (i.e., time to completion) best differentiated between low-stress and high-stress participants (89% accuracy, 100% sensitivity, 83.3% specificity, 75% precision, 85.7% F1 score). Overall, under technostress, high-stress participants experienced cognitive overload and consequently decreased performance; whereas, low-stress participants felt moderate arousal and improved performance. These varying effects of technostress can be interpreted through the Yerkes-Dodson law. Based on our findings, we proposed an adaptive interface, multimodal interaction, and virtual reality training as three implications for technostress relief in non-face-to-face ICT.

Eye Tracking in Virtual Reality: Vive Pro Eye Spatial Accuracy, Precision, and Calibration Reliability.

A growing number of virtual reality devices now include eye tracking technology, which can facilitate oculomotor and cognitive research in VR and enable use cases like foveated rendering. These applications require different tracking performance, often measured as spatial accuracy and precision. While manufacturers report data quality estimates for their devices, these typically represent ideal performance and may not reflect real-world data quality. Additionally, it is unclear how accuracy and precision change across sessions within the same participant or between devices, and how performance is influenced by vision correction. Here, we measured spatial accuracy and precision of the Vive Pro Eye built-in eye tracker across a range of 30 visual degrees horizontally and vertically. Participants completed ten measurement sessions over multiple days, allowing to evaluate calibration reliability. Accuracy and precision were highest for central gaze and decreased with greater eccentricity in both axes. Calibration was successful in all participants, including those wearing contacts or glasses, but glasses yielded significantly lower performance. We further found differences in accuracy (but not precision) between two Vive Pro Eye headsets, and estimated participants' inter-pupillary distance. Our metrics suggest high calibration reliability and can serve as a baseline for expected eye tracking performance in VR experiments.

Blink duration is increased in concussed youth athletes: a validity study using eye tracking in male youth and adult athletes of selected contact sports

Objective. Diagnosing a sports-related concussion (SRC) remains challenging, and research into diagnostic tools is limited. This study investigated whether selected eye tracking variables would be a valid tool to diagnose and monitor SRC in adult and youth participants in selected contact sports, such as Rugby Union (rugby) and football (soccer). Methods. This prospective cohort study, with 70 concussed and 92 non-concussed adult and youth athletes, assessed the validity of five previously selected eye tracking variables for SRC diagnostics and management. The performance between concussed and age-matched control (non-concussed) athletes, as well as between three successive testing sessions in the concussed athletes were compared. Self-paced saccade count in adult group; blink duration in the memory-guided saccade and sinusoidal smooth pursuit tasks, proportion of antisaccade errors, and gain of diagonal smooth pursuit in the youth group were assessed. Results. The youth concussed group had higher blink duration in the fast memory-guided saccades task (p = 0.001, η 2 = 0.17) and a tendency for higher blink duration in the sinusoidal smooth pursuit task (p = 0.016, η 2 = 0.06) compared to the youth control group. In both tasks the blink duration in the concussed youth group decreased from session 1 to session 2 by 24% and 18%, accordingly, although statistical significance was not reached. The concussed adult group demonstrated a lower number of self-paced saccades compared to controls (p = 0.05, η 2 = 0.09), which gradually increased, with the largest difference between session 1 and session 3 (p = 0.02). Conclusions. Blink duration in youth athletes holds promise as a valid metric for concussion diagnostics and monitoring. It is recommended to focus future studies on comparing eye tracking performance within the same concussed athletes over time rather than comparing them to healthy controls.

An Investigation on the Influence of Operation Experience on Virtual Hazard Perception Using Wearable Eye Tracking Technology.

Poor electrical hazard recognition is a widespread issue in the production industry. Hazard perception has impacts workers’ hazard recognition, causing them to experience unanticipated hazard exposure and suffer catastrophic injuries. To improve the factors of affecting hazard perception, the current study examined hazard recognition as an everyday visual search task. A comparative test was carried out combining the advantages and disadvantages of the two test methods. It was confirmed that the virtual image test data can replace the real image test data and demonstrate superior flexible settings performance, so the virtual image test method is used. A hazard perception test method based on wearable eye tracking technology was proposed to analyze the eye-tracking data (i.e., fixation, count, search duration, mean fixation duration, eye tracking, and hazard recognition performance feedback) were compared between experts in the field of electrical safety: skilled workers with at least five years of work experience and workers who had been on the job for less than a year. It was found that experts had a better hazard recognition accuracy and missed detection rate than other workers. Experts’ hazards research track was more concised and paid less attention time. This advantage is most obvious in complex risk environments. The findings also suggest that workers who have different working years was not obvious visual search patterns other than the search duration. As can be seen the work experience is not an absolute factor in improving hazard perception. The present research will be useful to understand the influence of working years on hazard perception and provide a theoretical basis for corresponding training.

Exploring the relationship between children's facial emotion processing characteristics and speech communication ability using deep learning on eye tracking and speech performance measures

The ability of efficient facial emotion recognition (FER) plays a significant role in successful human communication and is closely associated with multiple speech communication disorders (SCD) in children. Despite the relevance, little is known about how speech communication abilities (SCA) and FER are correlated or of their underlying mechanism. To address this, we monitored eye movements of 115 children while watching human faces with different emotions and designed a machine-learning based SCD prediction model to explore the underlying pattern of eye movements during the FER task as well as their correlation with SCA. Strong and detailed correlations were found between different dimensions of SCA and various eye-movement features. A group of FER gazing patterns was found to be highly sensitive to the possibility of children's SCD. The SCD prediction model reached an accuracy as high as 88.9%, which offers a possible technique to fast screen SCD for children.

Eye movements and stress during eye-tracking gaming performance in children with dyskinetic cerebral palsy.

This study aimed to explore eye movements and stress during eye-tracking gaming performance in children with dyskinetic cerebral palsy (CP) compared with typically developing children, and associations between eye-tracking performance, eye movements, stress, and participants' characteristics. This cohort study included 12 children with dyskinetic CP aged 5 to 12 years (mean age 8 years 7 months, standard deviation [SD] 2 years 3 months) and 23 typically developing children aged 5 to 13 years (mean age 9 years 0 months, SD 2 years 7 months). Participants played 10 eye-tracking games. Tobii X3-120 and Tobii Pro Lab were used to record and analyse eye movements. Stress was assessed through heart rate variability (HRV), recorded during rest, and eye-tracking performance using the Bittium Faros360° ECG Holter device. Eye-tracking performance was measured using gaming completion time. Fixation and saccade variables were used to quantify eye movements, and time- and frequency-domain variables to quantify HRV. Non-parametric statistics were used. Gaming completion time was significantly different (p< 0.001) between groups, and it was negatively correlated with experience (rs = -0.63, p= 0.029). No significant differences were found between groups in fixation and saccade variables. HRV significantly changed from rest to eye-tracking performance only in typically developing children and not in children with dyskinetic CP. Children with dyskinetic CP took longer to perform the 10 games, especially the inexperienced users, indicating the importance of the early provision of eye-tracking training opportunities. It seems that eye-tracking tasks are not a source of increased stress and effort in children with dyskinetic CP. Participants with dyskinetic cerebral palsy (CP) took twice as long to perform 10 eye-tracking games than typically developing peers. Participants with dyskinetic CP with previous eye-tracking experience performed the games faster. Fixation and saccade variables were not significantly different between children with and without dyskinetic CP. Heart rate variability showed no differences between rest and performance in participants with dyskinetic CP. Gross Motor Function Classification System, Manual Ability Classification System, and Viking Speech Scale levels were not correlated to the eye movements or stress variables.

An eye tracker based on webcam and its preliminary application evaluation in Chinese reading tests

There is increasing evidence that eye trackers can be used in neuroscience research to assess cognitive function although expensive prices or low availability still prevent its ubiquitous application. Meanwhile, in tasks such as reaction speed testing in cognitive function assessment, the requirements for spatial performance are less critical than temporal resolution. Therefore, in this report we propose an eye-tracking system based on a common web-camera, to evaluate if it's possible to achieve a decent temporal resolution for eye-tracking tasks in cognitive experiments and then further evaluate it in Chinese reading tests. The performance of the proposed setup are evaluated in comparison experiments including 62 healthy subjects, with a commercialized eye-tracker (SMI RED250) simultaneously deployed. It’s found in the results that the webcam-based system showed no significant difference in the recognition accuracy of occurrence and switching of the eye movement events compared with the SMI system though the spatial eye-tracking performance is significantly worse. Then in an application experiment, cognitive-related Chinese reading tests are adapted and EMs of 27 young (18–30 years) and 28 elderly (over 60 years) readers are recorded to study their difference in Chinese reading. In the results there are significant differences in reading-time-per-sentence between young and elderly subjects. Meanwhile, a study on the reading-time-per-sentence difference using reading materials of different difficulties shows that elderly subjects are more sensitive to difficulty changes. These results preliminary demonstrated the feasibility of a Chinese reading test with a web-camera setup as an alternative option when the expensive eye-tracker is not available.

Diagnosis and Management of Mild TBI via Eye Tracking

The purpose of this study is to expose the prevalence of mild traumatic brain injuries among high school football players and to explore the possibility of implementing eye tracking performance as an objective way to assess cases of potential concussion. Concussions are one of the most common forms of traumatic brain injury (TBI). Unfortunately, current research suggests that mild TBIs cannot always be accurately diagnosed via routine neurologic examination. Also, most evaluations, such as ImPACT, are survey-style assessments that are time intensive and subjective. Lack of an objective method to rapidly assess concussions on the field raises concern for second-impact syndrome (SIS), which can lead to permanent brain damage or even fatality. This multi-part study included a population of 849 high school athletes in from Lubbock, TX. Student athletes filled out a baseline concussion survey, then assessed their eye tracking performance with the EyeGuide Focus, a 10-second test that involves visually tracking a continuous, figure-8 shape. A vector-based system was used to measure the eye-tracking deviation. Forty-two athletes were recorded with a baseline eye-tracking score, and a subsequent eye-tracking score that was labelled as a suspected concussion by a physician. Of those 42, 17 had a follow-up eye-tracking test 2 weeks later. Test scores labelled with suspected concussion had a significantly higher mean raw score than the baseline score. Higher scores indicate greater vector deviation from accurately tracing the figure-8 with the eyes. The survey results show underdiagnosing of concussions at lower levels of youth sports, which may indicate a lack of resources. As the data shows marked changes between the concussed, baseline, and follow-up scores, eye-tracking promises to be a quick and efficient tool to assess sports-related concussions.

Visual Performance Assessment of Videos—A Case Study of the Game “Spot the Difference”

“Spot the Difference” is a well-known game where players must find subtle differences between two almost identical pictures. If “Spot the Difference” is designed for videos, what is the difference between videos and pictures? If the performance of videos is measured by an eye tracker, what scan paths will be conducted? In this study, we explored this game using a video to conduct a visual performance evaluation. Twenty-five subjects were recruited in a full-factorial experiment to investigate the effect of background (with background, without background), video type (animation, text), and arrangement (left-to-right, top-to-bottom) on searching, eye tracking performance, and visual fatigue. The results showed that the video type had a significant effect on the accuracy and subjective visual fatigue, with the accuracy and subjective visual fatigue for animation being better than for text. The results also indicated that the arrangement had a significant effect on the number of fixations, where top-to-bottom arrangement brought a higher number of fixations. The background had a significant effect on accuracy and subjective visual fatigue, where the accuracy and subjective visual fatigue without a background was better than with a background. For the analysis of the scan path, a denser scan path was found in text than in animation, in top-to-bottom arrangement than in left-to-right arrangement, and without a background than with a background. In the future, game manufacturers should use the results of this research to design different “Spot the Difference” videos. When designing a simple game, an animation without a background and involving a left-to-right arrangement was recommended. When designing a difficult game, the opposite settings should be used.

The Association between Baseline Eye Tracking Performance and Concussion Assessments in High School Football Players.

Concussions are complex injuries that require a multifaceted testing battery. Vision impairments are common after concussion, but it is unknown exactly how eye tracking may be affected after injury and how it is associated with other clinical concussion assessments. This study aimed to (1) examine the relationship between eye tracking performance (BOX score) and other common concussion evaluations, (2) identify if eye tracking adds novel information that augments baseline concussion evaluations, and (3) examine the effect of age, concussion history, and attention-deficit/hyperactivity disorder on eye tracking and other ophthalmological measures. A total of 102 male high school football athletes (age, 16.0 years; 95% confidence interval, 15.8 to 16.2 years) completed a series of visual and neurocognitive tests during their pre-season baseline assessment. The main outcome measures were BOX score, near point of convergence (NPC) distance, binocular accommodative amplitude (BAA) distance, Standardized Assessment of Concussion score, and Immediate Post-Concussion Assessment and Cognitive Testing composite scores. BOX score was not significantly associated with symptoms, Standardized Assessment of Concussion score, NPC distance, BAA distance, or any Immediate Post-Concussion Assessment and Cognitive Testing composite scores. Age, concussion history, attention-deficit/hyperactivity disorder, and number of prior years playing football were not significantly associated with BOX score or NPC distance, but there was a significant association between concussion history and greater BAA distance (β = 1.60; 95% confidence interval = 0.19 to 3.01; P < .03). The BOX score cutoff of 10 resulted in a 12% false-positive rate. Eye tracking was not significantly associated with the commonly used clinical concussion assessments. These results suggest that an objective eye tracking variable may be a valuable addition to the current concussion battery.

Video-based eye tracking performance for computer-assisted diagnostic support of diabetic neuropathy

Diabetes is currently one of the major public health threats. The essential components for effective treatment of diabetes include early diagnosis and regular monitoring. However, health-care providers are often short of human resources to closely monitor populations at risk. In this work, a video-based eye-tracking method is proposed as a low-cost alternative for detection of diabetic neuropathy. The method is based on the tracking of the eye-trajectories recorded on videos while the subject follows a target on a screen, forcing saccadic movements. Upon extraction of the eye trajectories, representation of the obtained time-series is made with the help of heteroscedastic ARX (H-ARX) models, which capture the dynamics and latency on the subject's response, while features based on the H-ARX model's predictive ability are subsequently used for classification. The methodology is evaluated on a population constituted by 11 control and 20 insulin-treated diabetic individuals suffering from diverse diabetic complications including neuropathy and retinopathy. Results show significant differences on latency and eye movement precision between the populations of control subjects and diabetics, while simultaneously demonstrating that both groups can be classified with an accuracy of 95%. Although this study is limited by the small sample size, the results align with other findings in the literature and encourage further research.

Writing with the Eyes: The Effect of Age on Eye-Tracking Performance in Non-Disabled Adults and a Comparison with Bimanual Typing.

Eye-tracking technology is advancing rapidly, becoming cheaper and easier to use and more robust. This has fueled an increase in its implementation for Augmentative and Alternative Communication (AAC). Nowadays, Eye-Tracking Communication Devices (ETCDs) can be an effective aid for people with disabilities and communication problems. However, it is not clear what level of performance is attainable with these devices or how to optimize them for AAC use. The objective of this observational study was to provide data on non-disabled adults' performance with ETCD regarding (a) range of eye-typing ability in terms of speed and errors for different age groups and (b) relationship between ETCD performance and bimanual writing with a conventional PC keyboard and (c) to suggest a method for a correct implementation of ETCD for AAC. Sixty-seven healthy adult volunteers (aged 20–79 years) were asked to type a sample sentence using, first, a commercial ETCD and then a standard PC keyboard; we recorded the typing speed and error rate. We repeated the test 11 times in order to assess performance changes due to learning. Performances differed between young (20–39 years), middle-aged (40–59 years), and elderly (60–79 years) participants. Age had a negative impact on performance: as age increased, typing speed decreased and the error rate increased. There was a clear learning effect, i.e., repetition of the exercise produced an improvement of performance in all subjects. Bimanual and ETCD typing speed showed a linear relationship, with a Pearson's correlation coefficient of 0.73. The assessment of the effect of age on eye-typing performance can be useful to evaluate the effectiveness of man-machine interaction for use of ETCDs for AAC. Based on our findings, we outline a potential method (obviously requiring further verification) for the setup and tuning of ETCDs for AAC in people with disabilities and communication problems.