Eye-tracking Equipment Research Articles

Posterior cortical atrophy: an investigation of scan paths generated during face matching tasks

When viewing a face, healthy individuals focus more on the area containing the eyes and upper nose in order to retrieve important featural and configural information. In contrast, individuals with face blindness (prosopagnosia) tend to direct fixations toward individual facial features—particularly the mouth. Presented here is an examination of face perception deficits in individuals with Posterior Cortical Atrophy (PCA). PCA is a rare progressive neurodegenerative disorder that is characterized by atrophy in occipito-parietal and occipito-temporal cortices. PCA primarily affects higher visual processing, while memory, reasoning, and insight remain relatively intact. A common symptom of PCA is a decreased effective field of vision caused by the inability to “see the whole picture.” Individuals with PCA and healthy control participants completed a same/different discrimination task in which images of faces were presented as cue-target pairs. Eye-tracking equipment and a novel computer-based perceptual task—the Viewing Window paradigm—were used to investigate scan patterns when faces were presented in open view or through a restricted-view, respectively. In contrast to previous prosopagnosia research, individuals with PCA each produced unique scan paths that focused on non-diagnostically useful locations. This focus on non-diagnostically useful locations was also present when using a restricted viewing aperture, suggesting that individuals with PCA have difficulty processing the face at either the featural or configural level. In fact, it appears that the decreased effective field of view in PCA patients is so severe that it results in an extreme dependence on local processing, such that a feature-based approach is not even possible.

Perception of Face and Body Expressions Using Electromyography, Pupillometry and Gaze Measures

Traditional emotion theories stress the importance of the face in the expression of emotions but bodily expressions are becoming increasingly important as well. In these experiments we tested the hypothesis that similar physiological responses can be evoked by observing emotional face and body signals and that the reaction to angry signals is amplified in anxious individuals. We designed three experiments in which participants categorized emotional expressions from isolated facial and bodily expressions and emotionally congruent and incongruent face-body compounds. Participants’ fixations were measured and their pupil size recorded with eye-tracking equipment and their facial reactions measured with electromyography. The results support our prediction that the recognition of a facial expression is improved in the context of a matching posture and importantly, vice versa as well. From their facial expressions, it appeared that observers acted with signs of negative emotionality (increased corrugator activity) to angry and fearful facial expressions and with positive emotionality (increased zygomaticus) to happy facial expressions. What we predicted and found, was that angry and fearful cues from the face or the body, attracted more attention than happy cues. We further observed that responses evoked by angry cues were amplified in individuals with high anxiety scores. In sum, we show that people process bodily expressions of emotion in a similar fashion as facial expressions and that the congruency between the emotional signals from the face and body facilitates the recognition of the emotion.

Visual expertise in detecting and diagnosing skeletal fractures

Failure to identify fractures is the most common error in accident and emergency departments. Therefore, the current research aimed to understand more about the processes underlying perceptual expertise when interpreting skeletal radiographs. Thirty participants, consisting of ten novices, ten intermediates, and ten experts were presented with ten clinical cases of normal and abnormal skeletal radiographs of varying difficulty (obvious or subtle) while wearing eye tracking equipment. Experts were significantly more accurate, more confident, and faster in their diagnoses than intermediates or novices and this performance advantage was more pronounced for the subtle cases. Experts were also faster to fixate the site of the fracture and spent more relative time fixating the fracture than intermediates or novices and this was again most pronounced for subtle cases. Finally, a multiple linear regression analysis found that time to fixate the fracture was inversely related to diagnostic accuracy and explained 34 % of the variance in this variable. The results suggest that the performance advantage of expert radiologists is underpinned by superior pattern recognition skills, as evidenced by a quicker time to first fixate the pathology, and less time spent searching the image.

What Do Surgeons See

Recording eye motions in surgical environments is challenging. This study describes the authors' experiences with performing eye-tracking for improving surgery training, both in the laboratory and in the operating room (OR). Three different eye-trackers were used, each with different capabilities and requirements. For monitoring eye gaze shifts over the room scene in a simulated OR, a head-mounted system was used. The number of surgeons' eye glances on the monitor displaying patient vital signs was successfully captured by this system. The resolution of the head-mounted eye-tracker was not sufficient to obtain the gaze coordinates in detail on the surgical display monitor. The authors then selected a high-resolution eye-tracker built in to a 17-inch computer monitor that is capable of recording gaze differences with resolution of 1° of visual angle. This system enables one to investigate surgeons' eye-hand coordination on the surgical monitor in the laboratory environment. However, the limited effective tracking distance restricts the use of this system in the dynamic environment in the real OR. Another eye-tracker system was found with equally high level of resolution but with more flexibility on the tracking distance, as the eye-tracker camera was detached from the monitor. With this system, the surgeon's gaze during 11 laparoscopic procedures in the OR was recorded successfully. There were many logistical challenges with unobtrusively integrating the eye-tracking equipment into the regular OR workflow and data processing issues in the form of image compatibility and data validation. The experiences and solutions to these challenges are discussed.

Reading paths and visual perception in multimodal research, psychology and brain sciences

This paper argues that the concept of a reading path in multimodal research can be improved by previous research on visual perception in psychology and brain sciences, and particularly by the work done within eye-tracking studies. The paper argues that in its current state, the concept of a reading path is not sufficiently reliable due to the lack of empirical testing and therefore presents a methodological proposal to improve the current situation.Thus, the paper identifies common areas of interest related to visual perception, where the research interests of the disciplines meet and enable reciprocal input. It is suggested that multimodal research is capable of describing the high-level factors that affect visual perception, whereas eye-tracking equipment can track the actual reader behaviour. Applicable state-of-the-art theories of multimodal analysis are then described, along with the technological requirements for the eye tracker and its software.XML annotation, output and transformations are proposed for combining the results of multimodal analysis and the observer behaviour captured using an eye tracker. Finally, the paper presents a hypothesis on the relationship of visual perception and multimodal semiosis, which may be evaluated using the proposed method combining multimodal analysis and eye-tracking.

Gliding and saccadic gaze gesture recognition in real time

Eye movements can be consciously controlled by humans to the extent of performing sequences of predefined movement patterns, or 'gaze gestures'. Gaze gestures can be tracked noninvasively employing a video-based eye tracking system. Gaze gestures hold the potential to become an emerging input paradigm in the context of human-computer interaction (HCI) as low-cost eye trackers become more ubiquitous. The viability of gaze gestures as an innovative way to control a computer rests on how easily they can be assimilated by potential users and also on the ability of machine learning algorithms to discriminate in real time intentional gaze gestures from typical gaze activity performed during standard interaction with electronic devices. In this work, through a set of experiments and user studies, we evaluate the performance of two different gaze gestures modalities, gliding gaze gestures and saccadic gaze gestures, and their corresponding real-time recognition algorithms, Hierarchical Temporal Memory networks and the Needleman-Wunsch algorithm for sequence alignment. Our results show that a specific combination of gaze gesture modality, namely saccadic gaze gestures, and recognition algorithm, Needleman-Wunsch, allows for reliable usage of intentional gaze gestures to interact with a computer with accuracy rates higher than 95% and completion speeds of around 1.5 to 2.5 seconds per gesture. The optimal gaze gesture modality and recognition algorithm do not interfere with otherwise standard human-computer gaze interaction, generating very few false positives during real time recognition and positive feedback from the users. These encouraging results and the low cost eye tracking equipment used, open up a new HCI paradigm for the fields of accessibility and interaction with smartphones, tablets, projected displays and traditional desktop computers.

The effects of using a portable music player on simulated driving performance and task-sharing strategies

This study examined the effects of performing scrollable music selection tasks using a portable music player (iPod Touch™) on simulated driving performance and task-sharing strategies, as evidenced through eye glance behaviour and secondary task performance. A total of 37 drivers (18–48 yrs) completed the PC-based MUARC Driver Distraction Test (DDT) while performing music selection tasks on an iPod Touch. Drivers’ eye glance behaviour was examined using faceLAB eye tracking equipment. Results revealed that performing music search tasks while driving increased the amount of time that drivers spent with their eyes off the roadway and decreased their ability to maintain a constant lane position and time headway from a lead vehicle. There was also evidence, however, that drivers attempted to regulate their behaviour when distracted by decreasing their speed and taking a large number of short glances towards the device. Overall, results suggest that performing music search tasks while driving is problematic and steps to prohibit this activity should be taken.

Wearable eye tracking for mental health monitoring

Pervasive healthcare is a promising field of research as small and unobtrusive on-body sensors become available. However, despite considerable advances in the field, current systems are limited in terms of the pathologies they can detect, particularly regarding mental disorders. In this work we propose wearable eye tracking as a new method for mental health monitoring. We provide two reviews: one of the state-of-the-art in wearable eye tracking equipment and a second one of the work in experimental psychology and clinical research on the link between eye movements and cognition. Both reviews show a significant potential of wearable eye tracking for mental health monitoring in daily life settings. This finding calls for further research on unobtrusive sensing equipment and novel algorithms for automated analysis of long-term eye movement data.

Behavioral Measures of Saccade Latency and Inhibition in Manifest and Premanifest Huntington's Disease

ABSTRACT Initiation and inhibition of saccadic eye movements has been shown to be impaired in patients with Huntington's disease (HD) and premanifest gene carriers (PMGC), and may provide biomarkers useful in tracking phenotypic change. Computerized behavioral tests of prosaccade latency and disinhibition presented to 31 non–gene carriers (NGC), 25 PMGC, and 12 HD patients. These tests provided quantitative performance measures without use of eye-tracking equipment. Significant differences on saccade tests were found, with PMGC intermediate between NGC and HD patients. Saccade latency discriminated PMGC from NGC, whereas saccade disinhibition discriminated PMGC from HD patients. Results suggest utility of behavioral saccade measures as premanifest indicators of phenoconversion in HD.

Are We Looking in the Wrong Place? Implications for Behavioural-Based Pain Assessment in Rabbits (Oryctolagus cuniculi) and Beyond?

BackgroundSuccessful observation of behaviour depends upon knowing both which behaviours to look for and focusing on the appropriate areas of the body to observe them. Behaviour based scoring systems have become increasingly widely used to assess animal pain and distress. Although studies are available demonstrating which behaviours need to be observed, there has been little attempt to assess how effectively observers apply such information when viewing an animal's behaviour.Methodology/Principal FindingsThis study used historical video recordings of New Zealand white rabbits (Oryctolagus cuniculi) considered to be experiencing varying degrees of post-operative pain to assess the pattern of observation and the ability to assess pain exhibited by both experienced and inexperienced human participants (n = 151). Eye tracking equipment was used to identify how quickly, how frequently, for how long different areas of the rabbit's body were attended to by the participants. Simple visual analgoue scoring was used to assess the pain experienced in each sequence. The results demonstrate that irrespective of their experience or gender, observers focus first, more frequently and for longer on the face, compared to the abdomen, ears, back and hindquarters of the rabbit and that participants were poor at identifying rabbits in pain. Observing the back and hindquarters was correlated with ‘correct’ assessments and observing the face was correlated with ‘incorrect’ assessments.ConclusionsIn conclusion, irrespective of experience and gender, observers focused on the face when using behaviour to assess pain and were unable to effectively identify rabbits in pain. Focusing on the face is unlikely to be effective when using behavioural indicators of pain since they involve other body areas. Alternatively, if animals exhibit pain-related facial expressions, then it could improve our ability to assess pain. In addition, these results have potential implications for the use of behaviour to assess how rabbits and potentially other species feel.

Glancing and Stopping Behavior of Motorcyclists and Car Drivers at Intersections

For the past decade, motorcycle fatalities have risen while other motor vehicle fatalities have declined. Many motorcycle fatalities occurred within intersections after a driver failed to see a motorcyclist. However, little is known about the behavior of motorcyclists when they negotiate an intersection. A study was undertaken to compare the behavior at intersections of an experienced group of motorcyclists when they were operating a motorcycle with their behavior when they were driving a car. Each participant navigated a course through low-volume, open roads. Participants wore eye-tracking equipment to record eye-glance information, and the motorcycle and car were instrumented with an onboard accelerometer and Global Positioning System apparatus. Results showed that participants were more likely to make last glances toward the direction of the most threatening traffic before they made a turn when they were driving a car than when they were riding a motorcycle. In addition, motorcyclists were less likely to come to a complete stop at a stop sign than car drivers. These results suggested that motorcyclists were exposing themselves to unnecessary risk. Specifically, motorcyclists frequently failed to make proper glances and practice optimal riding techniques. The behavior of the motorcyclists was compared with the current Motorcycle Safety Foundation curriculum. The results suggested that threat-response and delayed-apex techniques should be added to the training curriculum.

POD12 Development of a hands-free, eye-tracking version of the Trail Making Test

BackgroundThe Trail Making Test (TMT) is a two-part written tool for detecting executive dysfunction. Part A consists of joining a “trail” of ascending numbers, which serves as a control for...

Measurement and Experimentation in the Social Sciences

I propose to build an advanced data collection environment for the social sciences that maximizes opportunities for innovation, and is fast, cost effective, and easy for everyone in the scientific community to use. The core of this “laboratory” is a representative panel of households in the United States who have agreed to be available for regular interviews over the Internet. The Internet panel is representative in the sense that respondent recruitment is based on a probability sample. Internet access will not be a prerequisite for participation in the panel. If a respondent does not have Internet access at the time of recruitment into the panel, he or she will be provided with a laptop and broadband access. The laboratory will incorporate and pioneer new forms of data collection - including, but not limited to, smartphones, self-administered measurement devices for the collection of biomarkers, experience sampling, web cameras, Global Positioning System (GPS) devices, accelerometers to measure physical activity, and eye tracking equipment.

A moving goalkeeper distracts penalty takers and impairs shooting accuracy

When facing penalty kicks in football (soccer), goalkeepers frequently incorporate strategies that are designed to distract the kicker. However, no direct empirical evidence exists to ascertain what effect such visual distractions have on the attentional control, and performance, of footballers. Eighteen experienced footballers took five penalty kicks under counterbalanced conditions of threat (low vs. high) and goalkeeper movement (stationary vs. waving arms) while wearing eye-tracking equipment. Results suggested that participants were more distracted by a moving goalkeeper than a stationary one and struggled to disengage from a moving goalkeeper under situations of high threat. Significantly, more penalties were saved on trials when the goalkeeper was moving and shots were also generally hit closer to the goalkeeper (centrally) on these trials. The results provide partial support for the predictions of attentional control theory and implications for kickers and goalkeepers are discussed.

Toward Mobile Eye-Based Human-Computer Interaction

Current research on eye-based interfaces mostly focuses on stationary settings. However, advances in mobile eye-tracking equipment and automated eye-movement analysis now allow for investigating eye movements during natural behavior and promise to bring eye-based interaction into people's everyday lives. Recent developments in mobile eye tracking equipment point the way toward unobtrusive human-computer interfaces that will become pervasively usable in everyday life. The potential applications for the further capability to track and analyze eye movements anywhere and anytime calls for new research to develop and understand eye-based interaction in mobile daily life settings.

Using eye tracking to evaluate usability of user interfaces: Is it warranted?

The evaluation of the usability of user interfaces is a crucial element in the design of computer software and other products with user interfaces. Owing to the availability of good quality, affordable eye tracking equipment and the arguable visual nature of interacting with user interfaces, the use of this methodology in usability evaluation is increasing. However, recent studies indicate that the relationship between eye movements and task performance is not as straightforward as has been suggested previously. It was found that careful alterations in the design of user interfaces did not lead to the expected improvement in task performance. This calls into question the use of eye tracking as a tool to assess usability.

The Effect of Credibility-Related Design Cues on Responses to a Web-Based Message About the Breast Cancer Risks From Alcohol: Randomized Controlled Trial

BackgroundInternet sites typically contain visual design elements that are unrelated to the quality of the health information presented but that could influence credibility judgments and responses to health advice. To assess the effects of such design elements, or credibility cues, experimentally, we exposed women with different levels of weekly alcohol consumption to a website containing high quality but unpalatable information about a related health risk (breast cancer). The information was presented alongside either positive or negative credibility cues unrelated to information content.ObjectivesWe explored four research questions: (1) Did the cues influence how the women engaged with the site? (2) Did they influence how the women responded cognitively and emotionally? (3) Did they influence whether the women subsequently acted on the advice? (4) Did the impact of the cues vary with how much alcohol the women reported drinking?MethodA total of 85 women were randomly assigned to view one of two versions of a website containing the same high-quality content but different cues. One version had positive credibility cues (trustmarks), the other had negative ones (adverts, pharmaceutical sponsorship, and a donation button). Objective measures included visual attention (using eye-tracking equipment), time studying the material, and recall. Subjective measures included cognitive and affective responses and intention to change. Measures of subsequent behavior were taken 1 week later.ResultsFirst, the cues did not affect how long the women spent on the site or how long they spent reading the text. However, women in the negative cues condition spent more time looking at a donation button than those in the positive cues condition spent looking at a TRUSTe seal (β = −.43, P < .001) but less time looking at a logo (β = .43, P < .001) or at certain other features of the site. Those in the negative cues condition also recalled more site content (β = −.22, P = .048). Second, there were no effects of the cues on any of the measures of cognition, affect, vulnerability, or intentions. However, third, at follow-up, the positive cues had promoted greater alcohol reduction than the negative cues among those women who had previously reported drinking more heavily (β = −.22, P = .02). So, fourth, the responses to the cues did vary with how much alcohol the women typically drank.ConclusionsContent-irrelevant images and logos can influence the behavioral response to quality health-risk information. These effects may be subtle, changing with time.

Adolescent students’ reading during writing behaviors and relationships with text quality: an eyetracking study

This study employed eyetracking technology to investigate adolescent students’ reading processes as they composed and to explore relationships between these reading processes and text quality. A sample of 32 adolescent students composed narrative and expository texts while eyetracking equipment recorded their eye movements. Eye movements upon a computer monitor indicating reading processes during composing were coded according to their position in the emerging text, and were coded as: reading at the point of inscription (monitoring recently composed words); local reading (reading recently composed sentences); global reading (reading paragraphs); or prompt reading. It was hypothesized that two reading during writing behaviors, global reading and local reading, would be related to text quality. Results of the multinomial multilevel logistic regression analysis indicated significant relationships between two reading processes (local reading and reading at the point of inscription, but not global reading), composing rate, and text quality.

Gaze controlled games

The quality and availability of eye tracking equipment has been increasing while costs have been decreasing. These trends increase the possibility of using eye trackers for entertainment purposes. Games that can be controlled solely through movement of the eyes would be accessible to persons with decreased limb mobility or control. On the other hand, use of eye tracking can change the gaming experience for all players, by offering richer input and enabling attention-aware games. Eye tracking is not currently widely supported in gaming, and games specifically developed for use with an eye tracker are rare. This paper reviews past work on eye tracker gaming and charts future development possibilities in different sub-domains within. It argues that based on the user input requirements and gaming contexts, conventional computer games can be classified into groups that offer fundamentally different opportunities for eye tracker input. In addition to the inherent design issues, there are challenges and varying levels of support for eye tracker use in the technical implementations of the games.

메뉴 구조의 평가 방법론으로서 활성화 확산 모델의 타당성 검증: Eye-Tracking 접근 방법

This study was designed to validate Spreading Activation Theory (SAT) for an evaluation methodology for menu structure through Eye-Tracking approach. When a visual search is on the way, more eye fixations and time are necessary to visually process complex and vague area. From the aspect of recognition, well-designed menu structures were hypothesized to have fewer numbers of fixations and shorter duration because well-designed menu structures reflecting the users' mental model would be well matched with the product's menu structure, resulting in reducing the number of fixations and duration time. The results show that the shorter reaction times for SAT had significantly fewer numbers of fixation and shorter duration time as the hypothesis for this study stated. In conclusion, SAT was proved to be an effective evaluation methodology for menu structure with the eye tracking equipment. In addition, using SAT instead of the real performance experiment would be useful for designing user-centered systems and convenient information structures because SAT was proven to be the theoretical background for design and evaluation of menu structures.