Precise oculocentric mapping of transcranial magnetic stimulation-evoked phosphenes.

OBJECTIVE: Transcranial magnetic stimulation (TMS)-evoked phosphenes are oculocentric; their perceived location depends upon eye position. We investigated the accuracy and precision of TMS-evoked phosphene oculocentric mapping. METHODS: We evoked central phosphenes by stimulating early visual cortical areas with TMS, systematically examining the effect of eye position by asking participants to report the location of the evoked phosphene. We tested whether any systematic differences in the precision or accuracy of responses occurred as a function of eye position. RESULTS: Perceived phosphene locations map veridically to eye position, although there are considerable individual differences in the reliability of this mapping. CONCLUSIONS: Our results emphasize the need to carefully control eye movements when carrying out phosphene localization studies and suggest that individual differences in the reliability of the reported position of individual phosphenes must be considered.

A privacy-preserving approach to streaming eye-tracking data.

Eye-tracking technology is being increasingly integrated into mixed reality devices. Although critical applications are being enabled, there are significant possibilities for violating user privacy expectations. We show that there is an appreciable risk of unique user identification even under natural viewing conditions in virtual reality. This identification would allow an app to connect a user's personal ID with their work ID without needing their consent, for example. To mitigate such risks we propose a framework that incorporates gatekeeping via the design of the application programming interface and via software-implemented privacy mechanisms. Our results indicate that these mechanisms can reduce the rate of identification from as much as 85% to as low as 30%. The impact of introducing these mechanisms is less than 1.5° error in gaze position for gaze prediction. Gaze data streams can thus be made private while still allowing for gaze prediction, for example, during foveated rendering. Our approach is the first to support privacy-by-design in the flow of eye-tracking data within mixed reality use cases.

Visual attention towards food during unplanned purchases - A pilot study using mobile eye tracking technology.

This pilot study aims to investigate the relationships between consumers' weight status, energy density of food and visual attention towards food during unplanned purchase behavior in a real-world environment. After more than a decade of intensive experimental eye tracking research on food perception, this pilot study attempts to link experimental and field research in this area. Shopping trips of participants with different weight status were recorded with mobile eye tracking devices and their unplanned purchase behavior was identified and analyzed. Different eye movement measurements for initial orientation and maintained attention were analyzed. Differences in visual attention caused by energy density of food were found. There was a tendency across all participants to look at low energy density food longer and more often.

Autism Detection in Children by Combined Use of Gaze Preference and the M-CHAT-R in a Resource-Scarce Setting.

Most children with autism spectrum disorder (ASD), in resource-limited settings (RLS), are diagnosed after the age of four. Our work confirmed and extended results of Pierce that eye tracking could discriminate between typically developing (TD) children and those with ASD. We demonstrated the initial 15 s was at least as discriminating as the entire video. We evaluated the GP-MCHAT-R, which combines the first 15 s of manually-coded gaze preference (GP) video with M-CHAT-R results on 73 TD children and 28 children with ASD, 36-99 months of age. The GP-MCHAT-R (AUC = 0.89 (95%CI: 0.82-0.95)), performed significantly better than the MCHAT-R (AUC = 0.78 (95%CI: 0.71-0.85)) and gaze preference (AUC = 0.76 (95%CI: 0.64-0.88)) alone. This tool may enable early screening for ASD in RLS.

Use of Eye-Tracking Technology by Medical Students Taking the Objective Structured Clinical Examination: Descriptive Study.

BACKGROUND: The objective structured clinical examination (OSCE) is a test used throughout Spain to evaluate the clinical competencies, decision making, problem solving, and other skills of sixth-year medical students. OBJECTIVE: The main goal of this study is to explore the possible applications and utility of portable eye-tracking systems in the setting of the OSCE, particularly questions associated with attention and engagement. METHODS: We used a portable Tobii Glasses 2 eye tracker, which allows real-time monitoring of where the students were looking and records the voice and ambient sounds. We then performed a qualitative and a quantitative analysis of the fields of vision and gaze points attracting attention as well as the visual itinerary. RESULTS: Eye-tracking technology was used in the OSCE with no major issues. This portable system was of the greatest value in the patient simulators and mannequin stations, where interaction with the simulated patient or areas of interest in the mannequin can be quantified. This technology proved useful to better identify the areas of interest in the medical images provided. CONCLUSIONS: Portable eye trackers offer the opportunity to improve the objective evaluation of candidates and the self-evaluation of the stations used as well as medical simulations by examiners. We suggest that this technology has enough resolution to identify where a student is looking at and could be useful for developing new approaches for evaluating specific aspects of clinical competencies.

Gaze patterns to emotional faces throughout the adult lifespan.

Prior research indicates that there may be age-related differences in visual attention to emotional faces, and that this might contribute to older adults' difficulties perceiving emotional facial displays. However, the nature and magnitude of age differences in gaze patterns have been inconsistent. Study 1 therefore used meta-analytic methodology to quantify age effects in gazing to the eyes and mouths of faces in standard emotion perception tasks. The results showed that older adults displayed a moderate bias to look less at the eyes compared to younger adults (g = -.66), and a small bias to look more at the mouth (g = .32). However, for gazing at the eyes, the largest age effects were evident in response to emotionally neutral faces, suggesting that these visual biases reflect broader age-related differences in face processing, and not differences in how emotions specifically are processed. Also consistent with this possibility was the absence of any association between gaze patterns and emotion perception accuracy. Study 2 then provided the first empirical test of age-related differences in gaze patterns using a sample of young, middle-aged, and older adults. Again, older adults looked less at the eyes compared to younger adults. However, of particular interest was the finding that these visual biases appear to represent a linear decline. As with Study 1, no relationships emerged between emotion perception accuracy and gaze patterns. Together, these findings show that aging is associated with visual biases to facial stimuli that are unrelated to older adults' ability to perceive emotional displays. (PsycInfo Database Record (c) 2020 APA, all rights reserved).

3-Dimensional magnetic resonance imaging of the freely moving human eye.

Eye motion is a major confound for magnetic resonance imaging (MRI) in neuroscience or ophthalmology. Currently, solutions toward eye stabilisation include participants fixating or administration of paralytics/anaesthetics. We developed a novel MRI protocol for acquiring 3-dimensional images while the eye freely moves. Eye motion serves as the basis for image reconstruction, rather than an impediment. We fully reconstruct videos of the moving eye and head. We quantitatively validate data quality with millimetre resolution in two ways for individual participants. First, eye position based on reconstructed images correlated with simultaneous eye-tracking. Second, the reconstructed images preserve anatomical properties; the eye's axial length measured from MRI images matched that obtained with ocular biometry. The technique operates on a standard clinical setup, without necessitating specialized hardware, facilitating wide deployment. In clinical practice, we anticipate that this may help reduce burdens on both patients and infrastructure, by integrating multiple varieties of assessments into a single comprehensive session. More generally, our protocol is a harbinger for removing the necessity of fixation, thereby opening new opportunities for ethologically-valid, naturalistic paradigms, the inclusion of populations typically unable to stably fixate, and increased translational research such as in awake animals whose eye movements constitute an accessible behavioural readout.

Simulation in perfusion: evaluating the efficacy of a specific training with eye-tracking.

BACKGROUND: With the aim of integrating simulation training into the training of perfusionists, we examined whether the participants were able to transfer a specific learning content to the same and different situations and assessed their feedback on the simulation training. Eye-tracking was tested as a measure and supplemented by additional measures. METHODS: A 2 × 2 mixed design was used, with test time (pre- and post-test) and training group (same and different content training) as factors. In the pre- and post-test, the participant had to handle a critical situation on the cardiopulmonary bypass, namely, a drop in arterial partial oxygen pressure. Between the two test times, the participant practised under guidance the handling of either the same critical situation (Group 1) or a different one, that is, impaired venous return (Group 2). Dependent measures were fixations of the eyes on specific areas of interest on the heart-lung machine, measures of latency and subjective assessments. Moreover, participants gave feedback on the simulation training. RESULTS: Fixation analyses showed that the training led to an increased gaze on areas of interest relevant to the drop in arterial partial oxygen pressure in both groups, with a significant increase only for Group 1. The surveys revealed a great interest in the integration of simulation training into education. CONCLUSION: In combination with other measures, eye-tracking is suitable for the evaluation of simulation training. Due to the positive training effects and positive participant feedback, the integration of simulation into the training of perfusionists is advocated. Concerning transfer of learning content, more research is needed.

Eye Tracking as a Tool to Identify Mood in Aphasia: A Feasibility Study.

Background. Persons with aphasia often present with low mood/depression, which can negatively affect their quality of life. The validity and reliability of existing depression measures for aphasia have been called into question. Eye tracking in nonstroke populations is reliable in identifying low mood/depression. Depressed persons are biased to negative emotions compared with nondepressed persons and have an absence of bias to positive emotions. However, nondepressed persons may be biased to positive emotions. Objective. To examine the feasibility of using eye tracking to measure mood in persons with aphasia. Methods. We recruited 22 persons with chronic aphasia and 12 healthy controls. Participants completed 2 self-report measures of mood. They also viewed faces that showed happy, sad, and neutral facial expressions during eye tracking. We analyzed 2 eye tracking indices: initial gaze orientation and gaze maintenance to happy, sad, and neutral faces. Results. For initial gaze orientation, participants with aphasia fixated faster on emotional faces compared with healthy controls but directed their gaze less often to happy faces compared with healthy controls. For gaze maintenance components, the duration of first fixation and total fixation duration were shorter on sad faces for participants with aphasia compared with healthy controls. Conclusion. Use of eye tracking with faces representing different mood states is feasible in persons with aphasia. Although there were some similarities, participants with aphasia had different gaze patterns to emotional faces compared with healthy controls. Further research is needed to establish whether this is a valid and reliable method of mood assessment.

Mobile eye tracking and academic integrity: A proof-of-concept study in the United Arab Emirates.

Academic dishonesty has been identified as a significant problem for tertiary educational institutions in the Arab World and beyond. This study aimed to test the efficacy of mobile eye-tracking technology as a means of detecting instances of academic dishonesty during a closed-book exam. Participants were thirty (N = 30) college students attending a university in the United Arab Emirates. Two faculty members were recruited as proctors, and three student participants acted as cheats in the mock examination situation, while wearing mobile eye-tracking devices (eye-tracking glasses). Eye-tracking observations were recorded, replayed and analyzed, with the data and visualizations from each eye movement being captured at 30 millisecond intervals. The findings were independently coded for each instance of suspected academic dishonesty. Inter-rater reliability was established, and the detections were shared with the pseudo-cheats (participating students). The cheating instance detection rate was 100% using two independent observers. Every attempt at cheating, for example, looking at another student's exam, was successfully detected the observers independently watching the exam footage captured from the eye-tracking glasses. This unique study is, to the best of our knowledge, the first to explore the exploitation of mobile eye-tracking technology in the context of academic integrity promotion.

Gaze-Contingent Music Reward Therapy for Clinically Anxious 7- to 10-Year-Olds: An Open Multiple Baseline Feasibility Study.

This multiple-baseline open pilot trial examined feasibility, compliance, acceptability, and preliminary indices of efficacy of Gaze-Contingent Music Reward Therapy (GC-MRT) for anxious 7- to 10-year-old children. GC-MRT is a novel therapy for anxiety disorders that relies on eye-tracking technology and operant conditioning principles to divert attention toward neutral over threat stimuli, with music serving as a reward. Using a multiple-baseline design, 12 children (M age = 8.3 years, SD = .72, range = 7-10; 4 girls) with social anxiety disorder, generalized anxiety disorder, or separation anxiety disorder received 8 therapy sessions. Clinical status was determined via semistructured interviews and questionnaires. Patients were randomized to wait 1, 3, or 5 weeks between initial assessment and beginning of therapy. Self-reported anxiety was recorded weekly, and comprehensive clinical assessments were obtained pre- and posttreatment. All 12 patients completed the full course of GC-MRT within the allocated therapy period. Therapy credibility rates were moderate to high as reported by both children and parents. Clinician-rated anxiety levels remained consistent during baseline measurement and decreased significantly following treatment. Parent-reports also yielded significant reductions in child anxiety symptoms from pre- to posttreatment. However, child-reported anxiety did not change significantly. The results provide preliminary evidence for feasibility, acceptability, and efficacy of GC-MRT for young children with anxiety disorders. Efficacy should now be tested in randomized controlled trials.

Age differences in emotion perception in a multiple target setting: An eye-tracking study.

Research focusing on the association between age and emotion perception has revealed inconsistent findings, with some support for an age-related positivity effect, as predicted by socioemotional selectivity theory. We used the mood-of-the-crowd (MoC) task to investigate whether older adults judge a crowd consisting of happy and angry expressions to be dominated by happy faces more frequently. The task was to decide whether an array of faces included more angry or more happy faces. Accuracy, response times, and gaze movements were analyzed to test the hypothesis, derived from socioemotional selectivity theory, that age would be associated with a bias toward judging crowds as happy, and with longer and more numerous fixations on happy expressions. Seventy-six participants took part in the study representing 3 different age groups (young, middle-aged, old). Contrary to the hypothesis, older participants more often judged the emotional crowd to be angry compared with younger participants. Furthermore, whereas fixations were longer for happy faces than for angry faces in younger adults, this difference was not present in older adults. A decline in inhibitory processing in older adults as well as higher cognitive demands of the task are discussed as possible explanations for these findings. (PsycInfo Database Record (c) 2020 APA, all rights reserved).