Eye Movement Recordings Research Articles

Ocular Motor System Control Models and the Cerebellum: Hypothetical Mechanisms.

To review our studies and "top-down" models of saccadic intrusions and infantile nystagmus syndrome with the aim of hypothesizing areas of cerebellar connections controlling parts of the ocular motor subsystems involved in both types of function and dysfunction. The methods of eye-movement recording and modeling are described in detail in the cited references. Saccadic intrusions, such as square-wave jerks and square-wave oscillations, can be simulated by a single malfunction, whereas staircase saccadic intrusions required two independent malfunctions. The major infantile nystagmus syndrome waveforms are traceable to a failure to calibrate the damping ratio of the smooth pursuit system. The use of a behavioral ocular motor system model demonstrated how putative cerebellar dysfunctions could accurately simulate both the oscillations and the ocular motor responses seen in patients with both saccadic and pursuit disorders.

Multimodal Mild Depression Recognition Based on EEG-EM Synchronization Acquisition Network

In this paper, we used electroencephalography (EEG)-eye movement (EM) synchronization acquisition network to simultaneously record both EEG and EM physiological signals of the mild depression and normal controls during free viewing. Then, we consider a multimodal feature fusion method that can best discriminate between mild depression and normal control subjects as a step toward achieving our long-term aim of developing an objective and effective multimodal system that assists doctors during diagnosis and monitoring of mild depression. Based on the multimodal denoising autoencoder, we use two feature fusion strategies (feature fusion and hidden layer fusion) for fusion of the EEG and EM signals to improve the recognition performance of classifiers for mild depression. Our experimental results indicate that the EEG-EM synchronization acquisition network ensures that the recorded EM and EEG data require that both the data streams are synchronized with millisecond precision, and both fusion methods can improve the mild depression recognition accuracy, thus demonstrating the complementary nature of the modalities. Compared with the unimodal classification approach that uses only EEG or EM, the feature fusion method slightly improved the recognition accuracy by 1.88%, while the hidden layer fusion method significantly improved the classification rate by up to 7.36%. In particular, the highest classification accuracy achieved in this paper was 83.42%. These results indicate that the multimodal deep learning approaches with input data using a combination of EEG and EM signals are promising in achieving real-time monitoring and identification of mild depression.

Visual electrodiagnostics and eye movement recording - World Society of Pediatric Ophthalmology and Strabismus (WSPOS) consensus statement.

Visual electrodiagnostics and eye movement recording are important additional clinical tools in evaluation, diagnosing and management of ophthalmic and neurological disorders. Due to their objectiveness and non-invasiveness they can play an important role in pediatric ophthalmology. The WSPOS (World Society of Pediatric Ophthalmology and Strabismus) consensus statement gives insight into basic principles and highlights the clinical application of both visual electrodiagnostic tests and eye movement recording.

Videonystagmography and Posturography.

Videonystagmography (VNG) and posturography are two vestibular assessment techniques that are still in use today. VNG: VNG allows clinicians to observe and record eye movements in real-time. Compared with electronystagmography (ENG), VNG tracings are more detailed and can capture subtle clinical findings. The utility of the monothermal caloric screen has been proposed in various studies. When appropriate cut-offs are used, the monothermal screen can be completed with a low false-negative rate. Air is often used as a medium for caloric testing, though not without some controversy. When air and water are compared, the response magnitudes for air are consistently smaller than for water. However, the overall classification of the result appears to be generally the same regardless of the caloric medium used. Posturography: Concerns have been raised about the reliability and validity of posturographic measurements. Approaches and analysis techniques vary widely, and there is little consensus regarding the best approaches for assessment or interpretation. There is a need for standardized protocols. The portable and low-cost Nintendo Wii Balance Board (WBB) has inspired a surge in publications looking at the validity of the system for quantifying posturography and for balance training; preliminary findings are very promising.

Eye Movements in Neuropsychological Tasks.

This chapter reviews how recording and analysis of eye movements have been applied to understanding cognitive functioning in patients with neurological disease. Measures derived from the performance of instructed eye movement tests such as the anti-saccade and memory-guided saccade tasks have been shown to be associated with cognitive test performance and the early stages of neurodegenerative disorders including Alzheimer's and Parkinson's disease. Other researchers have taken an ecological approach and recorded the uninstructed pattern of saccades made by patients during performance of established neuropsychological tasks. Studies that have analysed the eye movement strategies used in a number of widely used tests are reviewed, including the Corsi blocks, Tower of London, 'CANTAB' Spatial Working Memory and Brixton Spatial Anticipation test. The findings illustrate that eye movements are not purely in the service of vision, but support visuospatial working memory and forward action planning. Eye movement tests and measures also have potential for application in the assessment and diagnosis of neurological disease and cognitive impairment. Establishing large-scale normative data sets in healthy older adults and use of machine learning multivariate classifier algorithms may be key to further developing eye tracking applications in neuropsychological assessment.

Регистрация движений глаз и когнитивный мониторинг как методы объективации процесса инсайтного решения

Current article highlights the results of the research of specific mechanisms of insight problem solving. It is based on the analysis of eye movement record data made by eye-tracker. The recorded data included average pupil diameter [mm] and fixation duration [ms]; the distribution of averaged eye movement values within the areas of interest during the manipulations with problem space was analyzed. The eye movement data was compared to the cognitive monitoring method data. The specificity of insight problems in comparison with non-insight (algorithmized) problems was validated. Several qualitative features of insight problem solving and the organization of problem space were revealed. Additionally, the priority of visual processing during insight problem solving was discovered: fixation duration increased in the “main problem” AOI.

The Effects of back lit Aircraft Instrument Displays on Pilots Fatigue and Performance

Abstract One of the latest trends in the global aviation industry is to use smart technologies and interfaces as time saving and efficiency tools. Larger flight instrument displays have replaced conventional, analogue, instruments and can be combined with touch screen efficiency tools. Their ever-increasing size brings with them issues relating to light emissions and eye absorption. Especially emissions of certain colours of light at certain times affecting the Pilots circadian rhythms and cause eye fatigue - which is recognised to have an impact on Pilots performance. (Davies R., 2018) This research paper complements the current study and measurement of stress, fatigue and human factors with respect to increasing artificial light intensity experienced by Pilots on the Flight Deck. The authors present the results of several measurements taken using a flight simulator which meets the current regulations for Pilot training. However, the conditions have been adjusted to the realistic conditions of a Flight Deck. The research results provide Air Operators, Airlines and aeronautical designers with valuable data on human behaviour and the reactions to Flight Deck environmental changes. For the purpose of our research, we decided to use eye monitoring technology to record eye movements to determine the pilot’s performance. Eye monitoring provides data on the number of eye movements, fixations and the durations of these.

Eye Gaze Markers Indicate Visual Attention to Threatening Images in Individuals with Chronic Back Pain.

Research into attentional biases and threatening, pain-related information has primarily been investigated using reaction time as the dependent variable. This study aimed to extend previous research to provide a more in depth investigation of chronic back pain and individuals’ attention to emotional stimuli by recording eye movement behavior. Individuals with chronic back pain (n = 18) were recruited from a back rehabilitation program and age and sex matched against 17 non-symptomatic controls. Participants’ eye movements were recorded whilst they completed a dot probe task, which included back pain specific threatening images and neutral images. There were no significant differences between chronic pain and control participants in attentional biases recorded using reaction time from the dot probe task. Chronic pain participants, however, demonstrated a significantly higher percentage of fixations, larger pupil diameter, a longer average fixation duration and faster first fixation to threatening compared to neutral images. They also had a significantly longer average fixation duration and larger pupil diameter to threatening images compared to control participants. The findings of this study suggest eye gaze metrics may provide a more sensitive measure of attentional biases in chronic pain populations. These findings may have important therapeutic implications for the patient and therapist.

Human-level saccade detection performance using deep neural networks.

Saccades are ballistic eye movements that rapidly shift gaze from one location of visual space to another. Detecting saccades in eye movement recordings is important not only for studying the neural mechanisms underlying sensory, motor, and cognitive processes, but also as a clinical and diagnostic tool. However, automatically detecting saccades can be difficult, particularly when such saccades are generated in coordination with other tracking eye movements, like smooth pursuits, or when the saccade amplitude is close to eye tracker noise levels, like with microsaccades. In such cases, labeling by human experts is required, but this is a tedious task prone to variability and error. We developed a convolutional neural network to automatically detect saccades at human-level accuracy and with minimal training examples. Our algorithm surpasses state of the art according to common performance metrics and could facilitate studies of neurophysiological processes underlying saccade generation and visual processing. NEW & NOTEWORTHY Detecting saccades in eye movement recordings can be a difficult task, but it is a necessary first step in many applications. We present a convolutional neural network that can automatically identify saccades with human-level accuracy and with minimal training examples. We show that our algorithm performs better than other available algorithms, by comparing performance on a wide range of data sets. We offer an open-source implementation of the algorithm as well as a web service.

Referential processing during reading: concurrent recordings of eye movements and head motion.

The present study utilized a new experimental set-up synchronizing eye movements and head motion for investigating referential change occurring in a reading task. We examined the effects of a change in narrative perspective during reading on eye movements and head motion. Forty-four participants read texts on a digital tablet, and both participants' eye movements and head movements were recorded using eye tracker and motion capture. The results showed longer eye fixation duration, longer reading time and decreasing head motions when perspective changed. Recent studies have supported the dynamic engagement hypothesis suggesting that there is a fluctuation in cognitive engagement reflected by postural movements. Our findings on head movements seem to validate this hypothesis of a bodily engagement in reading. The results provided by our study showed that the novel methodology of eye and head movement recordings we used was proven to be informative in studying the reader's embodiment during reading.

Eye Movements in the "Morris Maze" Spatial Working Memory Task Reveal Deficits in Strategic Planning.

Analysis of eye movements can provide insights into processes underlying performance of cognitive tasks. We recorded eye movements in healthy participants and people with idiopathic Parkinson disease during a token foraging task based on the spatial working memory component of the widely used Cambridge Neuropsychological Test Automated Battery. Participants selected boxes (using a mouse click) to reveal hidden tokens. Tokens were never hidden under a box where one had been found before, such that memory had to be used to guide box selections. A key measure of performance in the task is between search errors (BSEs) in which a box where a token has been found is selected again. Eye movements were found to be most commonly directed toward the next box to be clicked on, but fixations also occurred at rates higher than expected by chance on boxes farther ahead or back along the search path. Looking ahead and looking back in this way was found to correlate negatively with BSEs and was significantly reduced in patients with Parkinson disease. Refixating boxes where tokens had already been found correlated with BSEs and the severity of Parkinson disease symptoms. It is concluded that eye movements can provide an index of cognitive planning in the task. Refixations on locations where a token has been found may also provide a sensitive indicator of visuospatial memory integrity. Eye movement measures derived from the spatial working memory task may prove useful in the assessment of executive functions as well as neurological and psychiatric diseases in the future.

Nystagmus Findings and Hearing Recovery in Idiopathic Sudden Sensorineural Hearing Loss Without Dizziness.

To investigate the incidence of nystagmus in patients with sudden sensorineural hearing loss (SSNHL) without dizziness, and to evaluate the correlation of the presence of nystagmus with hearing recovery in those patients. Retrospective study. Tertiary referral academic medical center. Thirty-eight patients with SSNHL who did not complained of dizziness were enrolled. The presence of nystagmus was evaluated by recording eye movements, and if present, nystagmus was classified as direction-fixed or positional nystagmus. Vestibular function tests were performed, including caloric test. Of 33 idiopathic SSNHL patients without dizziness, nystagmus was observed in 22 patients (67%), of which 14 patients exhibited direction-fixed nystagmus, and 8 patients exhibited direction-changing nystagmus. Among the 14 patients with direction-fixed nystagmus, 9 displayed the paretic type, and 5 displayed the irritative type. Direction-changing nystagmus (n = 8) was defined as that in which the direction of nystagmus was changed in a supine head-roll test, and the geotropic type and apogeotropic type were observed in two and six patients, respectively. The mean initial pure tone threshold was 58.2 ± 28.1 dB and 57.3 ± 20.0 dB in SSNHL patients with and without nystagmus, respectively, which was not significantly different (p = 0.925). When hearing improvement was compared according to the presence of nystagmus, 39% (8 of 21) of patients with nystagmus were found to belong in the good prognosis group, and 72% (8 of 11) of patients without nystagmus were found to belong in the good prognosis group, which showed marginal statistical significance (p = 0.063). Nystagmus was observed in two-thirds of idiopathic SSNHL patients without dizziness, and the pattern of nystagmus was either direction fixed or direction changing. Because hearing recovery was worse in patients with nystagmus than those without it, the diagnosis of nystagmus, even in SSNHL patients without dizziness, may be important in evaluating the hearing prognosis.

Misresponse to Survey Questions: A Conceptual Framework and Empirical Test of the Effects of Reversals, Negations, and Polar Opposite Core Concepts

The authors propose a conceptual framework of misresponse to multi-item scales in surveys in which misresponse to items that are reversed relative to other items (reversal misresponse) is differentiated from misresponse to items that are negated (negation misresponse) and from misresponse to items whose core concept is the opposite of the core concept in regular items (polar opposite misresponse). The framework specifies two broad mechanisms to account for the three forms of misresponse: lack of motivation to process items in detail (“inattention”) and lack of ability to comprehend items accurately (“difficulty”). The authors propose a procedure to identify potential misresponse effects on the observed item responses and factor loadings, and they report two empirical studies to test the framework; the second study uses eye movement recordings to examine the underlying process. The findings reveal that polar opposite, reversed, and negated items contribute to misresponse to varying degrees and that difficulty rather than inattention may be a more potent cause of misresponse in surveys than has traditionally been acknowledged.

Identification of a novel GPR143 mutation in X-linked ocular albinism with marked intrafamilial phenotypic variability

Ocular albinism type 1 (OA1) is an X-linked inherited disease characterized by impaired visual acuity, congenital nystagmus, foveal hypoplasia, hypopigmentation of iris and fundus. It is caused by mutations in the G protein-coupled receptor143 (GPR143) gene. The genetic characteristics of OA1 have not been well defined in Asians. In this study, six members from three consecutive generations of a Korean family with OA1 were enrolled. We performed whole-exome sequencing followed by validation and segregation analysis. Two affected patients underwent detailed ophthalmic examinations and eye movement recordings. Of the two affected males, the proband had all classical phenotypes of OA1, but the other showed isolated foveal hypoplasia without nystagmus. We identified a hemizygous missense (c.623C > A, p.Ala208Glu) mutation of GPR143 in affected males. This mutation was also present as heterozygous in two obligate female carriers, and was not found in unaffected members. Our data expands thespectrum of phenotypes and genotype in GPR143 in Asians, and highlights the phenotypic heterogeneity in OA1.

Attention and Information Acquisition: Comparison of Mouse-Click with Eye-Movement Attention Tracking.

Attention is crucial as a fundamental prerequisite for perception. The measurement of attention in viewing and recognizing the images that surround us constitutes an important part of eye movement research, particularly in advertising-effectiveness research. Recording eye and gaze (i.e. eye and head) movements is considered the standard procedure for measuring attention. However, alternative measurement methods have been developed in recent years, one of which is mouse-click attention tracking (mcAT) by means of an on-line based procedure that measures gaze motion via a mouse-click (i.e. a hand and finger positioning maneuver) on a computer screen.Here we compared the validity of mcAT with eye movement attention tracking (emAT). We recorded data in a between subject design via emAT and mcAT and analyzed and compared 20 subjects for correlations. The test stimuli consisted of 64 images that were assigned to eight categories. Our main results demonstrated a highly significant correlation (p < 0.001) between mcAT and emAT data. We also found significant differences in correlations between different image categories. For simply structured pictures of humans or animals in particular, mcAT provided highly valid and more consistent results compared to emAT. We concluded that mcAT is a suitable method for measuring the attention we give to the images that surround us, such as photographs, graphics, art or digital and print advertisements.

A study of quiet eye's phenomenon in the shooting section of "laser run" of modern pentathlon.

The aim of the study was to evaluate the effects of the Quiet eye (QE) phenomenon on performances during the shooting section of "Laser Run" of Modern Pentathlon, in two samples of athletes (novices and experts). The "Laser Run" consists of running and shooting activities. The study involved 18 experienced athletes of the Italian National Team of Modern Pentathlon (i.e., "elite" group) and 18 young and nonexpert athletes of a local Pentathlon club (i.e., "novice" group). Participants performed, in ecological conditions, five trials of four series of shootings (as it occurs in the real competitions), for a total of 20 series. During the shooting trials, athletes wore a mobile Eye Tracking System to record eye movements (saccades, blinks, and fixations). Key measures of the study were QE parameters (QE Duration [QED], Relative QED [RQED], and QE Onset), as well as the performance (accuracy and time to perform the event). The results revealed that both groups of athletes had a longer QED, RQED, and an earlier onset during their best shots than during the worse ones. Furthermore, differences between the groups showed that elite athletes had an earlier onset and a shorter QED than the novice group of athletes. These results provide insightful information about different cognitive and perceptual processes involved in Modern Pentathlon's athletes' performances at both the elite and non-elite level.

Awareness of what is learned as a characteristic of hippocampus-dependent memory

We explored the relationship between memory performance and conscious knowledge (or awareness) of what has been learned in memory-impaired patients with hippocampal lesions or larger medial temporal lesions. Participants viewed familiar scenes or familiar scenes where a change had been introduced. Patients identified many fewer of the changes than controls. Across all of the scenes, controls preferentially directed their gaze toward the regions that had been changed whenever they had what we term robust knowledge about the change: They could identify that a change occurred, report what had changed, and indicate where the change occurred. Preferential looking did not occur when they were unaware of the change or had only partial knowledge about it. The patients, overall, did not direct their gaze toward the regions that had been changed, but on the few occasions when they had robust knowledge about the change they (like controls) did exhibit this effect. Patients did not exhibit this effect when they were unaware of the change or had partial knowledge. The findings support the idea that awareness of what has been learned is a key feature of hippocampus-dependent memory.

Health Literacy and Attention to Cigarette Health Warning Labels among Rural Smokers.

We evaluated the association of health literacy and attention to the pictorial imagery of 9 health warning labels (HWLs) in a tobacco advertisement among rural US smokers. We hypothesized that lower health literacy would be associated with greater visual attention to pictorial portions of HWLs and evaluated the association between health literacy and recall of advertisement elements. Adult smokers from Appalachian Ohio (N = 180) viewed a pictorial HWL encompassing 20% or 33% of a cigarette advertisement while eye tracking software recorded eye movements toward the advertisement. Health literacy was measured with The Short Test of Functional Health Literacy in Adults. Generalized linear regression revealed that every one-unit decrease in health literacy increased viewing time of the pictorial portion of the health warning label by 1.3 percentage points. Logistic regression revealed that the odds of recalling elements of the pictorial portion of the health warning label increased 20% for every one-unit increase in health literacy. Rural smokers with lower health literacy view pictorial portions of health warning labels longer than those with greater health literacy supporting that health literacy is an important consideration in health communications, including future cigarette warning labels.

The time course of processing emotion-laden words during sentence reading: Evidence from eye movements

While recent research has explored the effect that positive and negative emotion words (e.g., happy or sad) have on the eye-movement record during reading, the current study examined the effect of positive and negative emotion-laden words (e.g., birthday or funeral) on eye movements. Emotion-laden words do not express a state of mind but have emotional associations and connotations. The current results indicated that both positive and negative emotion-laden words have a processing advantage over neutral words, although the relative time-course of processing differs between words of positive and negative valence. Specifically, positive emotion-laden words showed advantages in early, late, and post-target measures, while negative emotion-laden words showed effects only in late and post-target measures.

Hybrid System for Engagement Recognition During Cognitive Tasks Using a CFS + KNN Algorithm.

Engagement is described as a state in which an individual involved in an activity can ignore other influences. The engagement level is important to obtaining good performance especially under study conditions. Numerous methods using electroencephalograph (EEG), electrocardiograph (ECG), and near-infrared spectroscopy (NIRS) for the recognition of engagement have been proposed. However, the results were either unsatisfactory or required many channels. In this study, we introduce the implementation of a low-density hybrid system for engagement recognition. We used a two-electrode wireless EEG, a wireless ECG, and two wireless channels NIRS to measure engagement recognition during cognitive tasks. We used electrooculograms (EOG) and eye tracking to record eye movements for data labeling. We calculated the recognition accuracy using the combination of correlation-based feature selection and k-nearest neighbor algorithm. Following that, we did a comparative study against a stand-alone system. The results show that the hybrid system had an acceptable accuracy for practical use (71.65 ± 0.16%). In comparison, the accuracy of a pure EEG system was (65.73 ± 0.17%), pure ECG (67.44 ± 0.19%), and pure NIRS (66.83 ± 0.17%). Overall, our results demonstrate that the proposed method can be used to improve performance in engagement recognition.