Eye Movement Measures Research Articles

The influence of predictability, visual contrast, and preview validity on eye movements and N400 amplitude: co-registration evidence that the N400 reflects late processes

ABSTRACT Two eye movement/EEG co-registration experiments investigated effects of predictability, visual contrast, and parafoveal preview in normal reading. Replicating previous studies, in Experiment 1 contrast and predictability additively influenced fixation durations, and in Experiment 2 invalid preview eliminated the predictability effect on early eye movement measures. In both experiments, predictability influenced the amplitude of the N400 component of the fixation-related potential. In Experiment 1, visual contrast did not influence the N400, and in Experiment 2, the effect of predictability on the N400 was larger with invalid preview, in opposition to the eye movement pattern. The N400 may reflect a late process of accessing conceptual representations while the duration of the eyes’ fixation on a word is sensitive to the difficulty of perceptual encoding and early stages of word recognition. The effects of predictability on both fixation duration and the N400 suggest an influence of this variable at two distinct processing stages.

Contextualizing Visualizations of Digital Health Information among Young and Older Adults Based on Eye-Tracking

Visualizations have been found to be a promising solution to aid individuals’ comprehension of digital health information. However, how visualizations can be better contextualized remains unclear. This study aimed to examine the effects of visualizations of digital health information with various contextual cues and age on comprehension through eye-tracking techniques. A two-way mixed design was employed, with visualization (basic, color, color + text, and color + text + personalized statement) and age (young and older adults) as independent variables. Forty-one participants attended an experiment where they were asked to perform verbatim comprehension and value interpretation tasks in response to varied visualizations of digital health information. The results indicated that the four visualizations yielded comparable task completion time and accuracy. Older adults had longer task completion time and more errors compared with their counterparts. While eye movement measures were comparable across different visualizations, they were mostly affected by age and areas of interests. Different visualizations might attract different patterns of visual attention and yield varied effectiveness across age groups. Future research should focus on how to better visualize digital health information for older adults. Design practitioners should carefully consider how to attract patients’ visual attention to important information to improve comprehension.

Pathogenesis of Comorbid ADHD and Chinese Developmental Dyslexia: Evidence From Eye-Movement Tracking and Rapid Automatized Naming

Background: ADHD and Chinese developmental dyslexia (DD) have a very high comorbidity rate; however, which cognitive deficits characterize the comorbidity and when they occur during cognitive processing are still under debate. Methods: Rapid automatic naming (RAN) tasks with eye-movement tracking were conducted with 75 children who were typically developing, had comorbid ADHD and DD, had only ADHD, and had only DD. Results: The clinical groups had longer first fixation durations than the control for RAN digits. Temporal eye-movement measures, such as gaze duration and total reading time, were found to vary between the comorbidity and ADHD groups. Spatial eye-movement measures, such as regression probability and incoming saccade amplitude, differed between the comorbidity and DD groups. Conclusions: These results indicate that investigation with eye-movement measures combined with RAN tasks can strengthen the understanding of the pathogenesis of comorbid ADHD and DD.

Reliability of MUSE 2 and Tobii Pro Nano at capturing mobile application users' real-time cognitive workload changes.

Despite the importance of cognitive workload in examining the usability of smartphone applications and the popularity of smartphone usage globally, cognitive workload as one attribute of usability tends to be overlooked in Human-Computer Interaction (HCI) studies. Moreover, limited studies that have examined the cognitive workload aspect often measured some summative workloads using subjective measures (e.g., questionnaires). A significant limitation of subjective measures is that they can only assess the overall, subject-perceived cognitive workload after the procedures/tasks have been completed. Such measurements do not reflect the real-time workload fluctuation during the procedures. The reliability of some devices on a smartphone setting has not been thoroughly evaluated. This study used mixed methods to empirically study the reliability of an eye-tracking device (i.e., Tobii Pro Nano) and a low-cost electroencephalogram (EEG) device (i.e., MUSE 2) for detecting real-time cognitive workload changes during N-back tasks. Results suggest that the EEG measurements collected by MUSE 2 are not very useful as indicators of cognitive workload changes in our setting, eye movement measurements collected by Tobii Pro Nano with mobile testing accessory are useful for monitoring cognitive workload fluctuations and tracking down interface design issues in a smartphone setting, and more specifically, the maximum pupil diameter is the preeminent indicator of cognitive workload surges. In conclusion, the pupil diameter measure combined with other subjective ratings would provide a comprehensive user experience assessment of mobile applications. They can also be used to verify the successfulness of a user interface design solution in improving user experience.

O064 A Portable Ocular Assessment for Predicting Fitness to Drive under Extended-Wakefulness Conditions – Preliminary Analysis

Abstract Introduction In response to the high incidence of fatigue-based vehicle accidents, roadside assessments of sleepiness are in significant demand. For this purpose, we’ve piloted the existing NeuroFlex® Platform, which takes ocular performance measurements of both prosaccade and antisaccade eye-movements using a portable Virtual Reality (VR) headset. We’ve conducted preliminary comparisons between these measures and simulated driving performance. Methods Sixteen young-adults (females= 8; age M= 25.13, SD= 4.30) completed five test batteries starting 1-hour post-wake where repeated testing encapsuled more than 24-hours of extended wakefulness. Each battery consisted of one 60-minute drive on the AusEd driving simulator, in addition to three administrations of 60-second prosaccade and antisaccade assessments using the NeuroFlex® VR platform. Results Steering deviations from the median lane position showed a time main effect, F(4,24.49) = 13.38, p <.001, with the most diminished performance occurring at 19 (M=59.50cm, SD=26.61cm) and 25-hours post-wake (M=72.88cm, SD= 40.09cm) (vs. peak performance @13-hours post-wake M=35.09, SD=12.81; M diff.= 24.41 and 37.79 respectively, p <.001). One moderate association between prosaccade latency and steering deviation was found in the final battery following 25-hours of wakefulness (r=.51, p= 0.04). No significant associations were found for antisaccade latency. Discussion Despite the lack of significant associations with steering deviations, eye-movement latency did demonstrate durational increases over extended wakefulness. In this preliminary investigation we were limited to the existing output generation of the NeuroFlex® platform. Therefore, with refined data analyses of ocular control, we see promise in the NeuroFlex® platforms capability of detecting road users’ fitness to drive.

P021 Associations between Virtual Reality (VR) Ocular Assessments and Vigilance during Extended Wakefulness – Preliminary Analysis

Abstract Introduction Sustained vigilance is essential for safety in high-risk workplaces, making rapid and accessible alertness failure vulnerability assessments extremely desirable. We are piloting existing technology, the NeuroFlex® Platform, which takes ocular performance measurements of both prosaccade and antisaccade eye-movements using a portable Virtual Reality (VR) headset. We’ve conducted preliminary comparisons between these measures and Psychomotor Vigilance during extended wakefulness. Methods Sixteen young-adults (females= 8; age M= 25.13, SD= 4.30) completed five test batteries starting 1-hour post-wake where repeated testing encapsuled more than 24-hours of extended wakefulness. Each battery consisted of two 10-minute visual Psychomotor Vigilance Tasks, in addition to three administrations of 60-second prosaccade and antisaccade assessments using the NeuroFlex® VR platform. Results Time main effects occurred for reciprocal reaction time, F(3.83,57.37) = 20.54, p <.001, and proportions of lapses/trials, F(3.55,48.33) = 7.36, p <.001. Vigilance troughs occurred around the circadian nadir (19-hours post-wake) with some recovery at final administrations (25-hours post-wake). No associations were found between prosaccade latency and vigilance metrics. Moderate negative (r=-.63, p=.01 & r=-.54, p=.03) associations were found between antisaccade latency and reciprocal reaction time near the nadir, but not the number of lapses per trial. Discussion This preliminary analysis has demonstrated potential sensitivity of the NeuroFlex® platforms ocular measurements to vigilance. Though we have not detected associations between lapses and eye-movement latency, we were limited to the existing output generation of the NeuroFlex® platform in this preliminary investigation. With refined data analyses, we see promise in the NeuroFlex® platforms capability of predicting alertness failure.

Behavioral and neural representation of expected reward and risk

When faced with uncertainty, individuals’ value-based decisions are influenced by the expected rewards and risks. Understanding how reward and risk are processed and integrated at the behavioral and neural levels is essential for building up utility theories. Using a modified monetary incentive delay task in which the mean of two possible outcomes (expected reward) and the standard deviation (SD) of the possible outcomes (risk) were parametrically manipulated and orthogonalized, we measured eye movements, response times (RTs), and brain activity when participants seek to secure a reward. We found that RTs varied as a function of the mean but not the SD of the potential reward, suggesting that expected rewards are the main driver of RTs. Moreover, the difference between gazes focused on high vs. low value rewards became smaller when the magnitude of the potential reward (mean of possible outcomes) was larger and when risk (SD of possible outcomes) became smaller, highlighting that reward and risk have different effects on attention deployment. Processing the mean reward activated the striatum. The positive striatal connectivity to the amygdala and negative striatal connectivity to the superior frontal gyrus were correlated with individuals’ sensitivity to the expected reward. In contrast, processing risk activated the anterior insula. Its positive connectivity to the ventromedial prefrontal cortex and negative connectivity to the anterior midcingulate cortex were correlated with individual differences in risk sensitivity, further suggesting the functional dissociation of reward and risk at the neural level. Our findings, based on several different measures, delineate the distinct representations of reward and risk in non-decision contexts and provide insight into how these utility parameters modulate attention, motivation, and brain networks.

Developmental trajectories of eye movements in oral and silent reading for beginning readers: a longitudinal investigation

Eye movements provide a sensitive window into cognitive processing during reading. In the present study, we investigated beginning readers’ longitudinal changes in temporal and spatial measures of eye movements during oral versus silent reading, the extent to which variation in eye movements is attributable to individual differences and text differences, and the functional form of growth trajectories of eye-movement variables. Data were from 363 English-speaking children (52% male; 59.8% White) in the US who were followed longitudinally from Grade 1 to Grade 3. Results showed a rapid decrease in temporal eye-movement measures (e.g., first fixation) and an increase in spatial eye-movement measures (initial landing position) in both oral and silent reading. The majority of variance in eye movements was attributable to individual differences whereas some variance in initial landing position was due to text differences. Most eye-movement measures had nonlinear growth trajectories where fast development tapered off near the end of Grade 3 while initial fixation count and total gaze count in silent reading had a linear growth trajectory. The findings provide a first large-scale look into the developmental progression of eye movements during oral and silent reading during a critical period when reading skills rapidly develop.

The impact of aging and repetition on eye movements and recognition memory

ABSTRACT The modulation of gaze fixations on neural activity in the hippocampus, a region critical for memory, has been shown to be weaker in older adults compared to younger adults. However, as such research has relied on indirect measures of memory, it remains unclear whether the relationship between visual exploration and direct measures of memory is similarly disrupted in aging. The current study tested older and younger adults on a face memory eye-tracking task previously used by our group that showed that recognition memory for faces presented across variable, but not fixed, viewpoints relies on a hippocampal-dependent binding function. Here, we examined how aging influences eye movement measures that reveal the amount (cumulative sampling) and extent (distribution of gaze fixations) of visual exploration. We also examined how aging influences direct (subsequent conscious recognition) and indirect (eye movement repetition effect) expressions of memory. No age differences were found in direct recognition regardless of facial viewpoint. However, the eye movement measures revealed key group differences. Compared to younger adults, older adults exhibited more cumulative sampling, a different distribution of fixations, and a larger repetition effect. Moreover, there was a positive relationship between cumulative sampling and direct recognition in younger adults, but not older adults. Neither age group showed a relationship between the repetition effect and direct recognition. Thus, despite similar direct recognition, age-related differences were observed in visual exploration and in an indirect eye-movement memory measure, suggesting that the two groups may acquire, retain, and use different facial information to guide recognition.

Social cognition deficits and biometric signatures in the behavioural variant of Alzheimer's disease.

The behavioural variant of Alzheimer's disease (bvAD) is characterized by early predominant behavioural changes, mimicking the behavioural variant of frontotemporal dementia (bvFTD), which is characterized by social cognition deficits and altered biometric responses to socioemotional cues. These functions remain understudied in bvAD. We investigated multiple social cognition components (i.e. emotion recognition, empathy, social norms and moral reasoning), using the Ekman 60 faces test, Interpersonal Reactivity Index, empathy eliciting videos, Social Norms Questionnaire and moral dilemmas, while measuring eye movements and galvanic skin response. We compared 12 patients with bvAD with patients with bvFTD (n = 14), typical Alzheimer's disease (tAD, n = 13) and individuals with subjective cognitive decline (SCD, n = 13), using ANCOVAs and age- and sex-adjusted post hoc testing. Patients with bvAD (40.1 ± 8.6) showed lower scores on the Ekman 60 faces test compared to individuals with SCD (49.7 ± 5.0, P < 0.001), and patients with tAD (46.2 ± 5.3, P = 0.05) and higher scores compared to patients with bvFTD (32.4 ± 7.3, P = 0.002). Eye-tracking during the Ekman 60 faces test revealed no differences in dwell time on the eyes (all P > 0.05), but patients with bvAD (18.7 ± 9.5%) and bvFTD (19.4 ± 14.3%) spent significantly less dwell time on the mouth than individuals with SCD (30.7 ± 11.6%, P < 0.01) and patients with tAD (32.7 ± 12.1%, P < 0.01). Patients with bvAD (11.3 ± 4.6) exhibited lower scores on the Interpersonal Reactivity Index compared with individuals with SCD (15.6 ± 3.1, P = 0.05) and similar scores to patients with bvFTD (8.7 ± 5.6, P = 0.19) and tAD (13.0 ± 3.2, P = 0.43). The galvanic skin response to empathy eliciting videos did not differ between groups (all P > 0.05). Patients with bvAD (16.0 ± 1.6) and bvFTD (15.2 ± 2.2) showed lower scores on the Social Norms Questionnaire than patients with tAD (17.8 ± 2.1, P < 0.05) and individuals with SCD (18.3 ± 1.4, P < 0.05). No group differences were observed in scores on moral dilemmas (all P > 0.05), while only patients with bvFTD (0.9 ± 1.1) showed a lower galvanic skin response during personal dilemmas compared with SCD (3.4 ± 3.3 peaks per min, P = 0.01). Concluding, patients with bvAD showed a similar although milder social cognition profile and a similar eye-tracking signature to patients with bvFTD and greater social cognition impairments and divergent eye movement patterns compared with patients with tAD. Our results suggest reduced attention to salient facial features in these phenotypes, potentially contributing to their emotion recognition deficits.

Effect of multiple monitoring requests on vigilance and readiness by measuring eye movement and takeover performance

Drivers do not need to supervise the L3 automated driving system but have to resume dynamic driving tasks when necessary, where the takeover request system plays a crucial role in alerting drivers to take over control. Previous studies have investigated the feasibility of the two-stage takeover system, which divides the takeover request system into monitoring requests and takeover requests. However, whether it will affect drivers’ situation awareness and takeover performance if the monitoring request is issued multiple times without the takeover request has not been fully considered. This research conducted a driving simulation study to investigate the effect of multiple monitoring requests on participants’ vigilance to monitoring requests and readiness for takeover requests by measuring their eye movement and takeover performance. Forty-two participants experienced three kinds of takeover conditions: no monitoring request, once monitoring request, and four monitoring requests. Simultaneously, the eye movement and takeover performance of participants were recorded and analyzed. Results showed that participants gained sufficient situation awareness in the monitoring request phase and showed better takeover performance in the two-stage takeover system than the single-stage takeover system. However, participants’ vigilance to the monitoring request and readiness for the takeover request decreased after experiencing multiple monitoring requests. Specifically, 62% and 59% of participants put their hands on the steering wheel during the monitoring request phase when experiencing the first monitoring request, which decreased to 35% after experiencing four monitoring requests. Moreover, after experiencing multiple monitoring requests, more participants shifted their attention to non-driving-related tasks after first observing the road and with a reduced percentage of time in the road center. These findings suggest that the monitoring request should be more reasonable to avoid reducing the vigilance and readiness of drivers to take advantage of the two-stage takeover system effectively.

Predicting Product Preferences on Retailers' Web Shops through Measurement of Gaze and Pupil Size Dynamics.

Previous studies used gaze behavior to predict product preference in value-based decision-making, based on gaze angle variables such as dwell time, fixation duration and the first fixated product. While the application for online retail seems obvious, research with realistic web shop stimuli has been lacking so far. Here, we studied the decision process for 60 Dutch web shops of a variety of retailers, by measuring eye movements and pupil size during the viewing of web shop images. The outcomes of an ordinal linear regression model showed that a combination of gaze angle variables accurately predicted product choice, with the total dwell time being the most predictive gaze dynamic. Although pupillometric analysis showed a positive relationship between pupil dilation and product preference, adding pupil size to the model only slightly improved the prediction accuracy. The current study holds the potential to substantially improve retargeting mechanisms in online marketing based on consumers’ gaze information. Also, gaze-based product preference proves to be a valuable metric in pre-testing product introductions for market research and prevent product launches from failure.

Stable Working Memory and Perceptual Representations in Macaque Lateral Prefrontal Cortex during Naturalistic Vision.

Primates use perceptual and mnemonic visuospatial representations to perform everyday functions. Neurons in the lateral prefrontal cortex (LPFC) have been shown to encode both of these representations during tasks where eye movements are strictly controlled and visual stimuli are reduced in complexity. This raises the question of whether perceptual and mnemonic representations encoded by LPFC neurons remain robust during naturalistic vision-in the presence of a rich visual scenery and during eye movements. Here we investigate this issue by training macaque monkeys to perform working memory and perception tasks in a visually complex virtual environment that requires navigation using a joystick and allows for free visual exploration of the scene. We recorded the activity of 3950 neurons in the LPFC (areas 8a and 9/46) of two male rhesus macaques using multielectrode arrays, and measured eye movements using video tracking. We found that navigation trajectories to target locations and eye movement behavior differed between the perception and working memory tasks, suggesting that animals used different behavioral strategies. Single neurons were tuned to target location during cue encoding and working memory delay, and neural ensemble activity was predictive of the behavior of the animals. Neural decoding of the target location was stable throughout the working memory delay epoch. However, neural representations of similar target locations differed between the working memory and perception tasks. These findings indicate that during naturalistic vision, LPFC neurons maintain robust and distinct neural codes for mnemonic and perceptual visuospatial representations.SIGNIFICANCE STATEMENT We show that lateral prefrontal cortex neurons encode working memory and perceptual representations during a naturalistic task set in a virtual environment. We show that despite eye movement and complex visual input, neurons maintain robust working memory representations of space, which are distinct from neuronal representations for perception. We further provide novel insight into the use of virtual environments to construct behavioral tasks for electrophysiological experiments.

Emphasizing speed or accuracy in an eye-tracking version of the Trail-Making-Test: Towards experimental diagnostics for decomposing executive functions.

The Trail-Making-Test (TMT) is one of the most widely used neuropsychological tests for assessing executive functions, the brain functions underlying cognitively controlled thought and action. Obtaining a number of test scores at once, the TMT allows to characterize an assortment of executive functions efficiently. Critically, however, as most test scores are derived from test completion times, the scores only provide a summary measure of various cognitive control processes. To address this problem, we extended the TMT in two ways. First, using a computerized eye-tracking version of the TMT, we added specific eye movement measures that deliver a richer set of data with a higher degree of cognitive process specificity. Second, we included an experimental manipulation of a fundamental executive function, namely participants’ ability to emphasize speed or accuracy in task performance. Our study of healthy participants showed that eye movement measures differed between TMT conditions that are usually compared to assess the cognitive control process of alternating between task sets for action control. This demonstrates that eye movement measures are indeed sensitive to executive functions implicated in the TMT. Crucially, comparing performance under cognitive control sets of speed vs. accuracy emphasis revealed which test scores primarily varied due to this manipulation (e.g., trial duration, number of fixations), and which were still more sensitive to other differences between individuals (e.g., fixation duration, saccade amplitude). This provided an experimental construct validation of the test scores by distinguishing scores primarily reflecting the executive function of emphasizing speed vs. accuracy and those independent from it. In sum, both the inclusion of eye movement measures and of the experimental manipulation of executive functions in the TMT enabled a more specific interpretation of the TMT in terms of cognitive functions and mechanisms, which offers more precise diagnoses in clinical applications and basic research.

Measurement of Fixational Eye Movements With the Head-Mounted Perimeter Imo.

PurposeAlthough visual field testing is conducted with the subject gazing at a fixation target, constant minute eye movements, called fixational eye movements, do occur during fixation. We examined dynamic changes in fixational eye movements associated with stimulus presentation during visual field testing.MethodsWe used the head-mounted perimeter imo, which is capable of measurement under binocular conditions, with the frame rate of its fixation monitoring camera improved to 300 Hz, to assess fixational eye movements in 18 healthy individuals. We measured changes in fixational eye movements during testing under monocular and binocular conditions and analyzed these changes based on the bivariate contour ellipse area (BCEA). We also assessed the changes in the horizontal and vertical microsaccade rates separately.ResultsBoth the BCEA and horizontal microsaccade rates were higher at 400 to 600 msec after stimulus presentation than during stimulus presentation (P < 0.01). Additionally, the BCEA and vertical microsaccade rates were significantly lower in the binocular condition than in the monocular condition (P < 0.01 and P < 0.05, respectively). We did not observe a significant correlation between the test locations and microsaccade direction during visual field testing.ConclusionsFixational eye movements, especially vertical microsaccade rates, were lower in the binocular condition than in the monocular condition. Visual field testing under binocular conditions is a useful method for suppressing fixational eye movements and stabilizing the fixation during testing and may improve the reliability of the test results.Translational RelevanceVisual field testing under binocular conditions can make the fixation more stable during the testing compared with monocular conditions.

Tracking reading development in an English language university-level bridging program: evidence from eye-movements during passage reading

AbstractIncreasing numbers of international students enter university education via English language bridging programs. Much research has overlooked the nature of second language reading development during a bridging program, focusing instead on the development of literacy skills of international students who already meet the language requirement for undergraduate admission. We report a longitudinal eye-movement study assessing English passage reading efficiency and comprehension in 405 Chinese-speaking bridging program students. Incoming IELTS reading scores were used as an index of baseline reading ability. Linear mixed-effects regression models fitted to global eye-movement measures and reading comprehension indicated that despite initial between-subjects differences, within-subject change at each ability level progressed at the same rate, following parallel growth trajectories. Therefore, there was significant overall reading progress during the bridging program, but no evidence that the gap between low and high ability readers either closed or widened over time.

Effects of Mindset and Dietary Restraint on Attention Bias for Food and Food Intake.

Evidence for attention bias (AB) for food in restrained eaters is inconsistent. A person’s mindset related to food – that is, whether someone focuses on the hedonic or health aspects of food – might be an overlooked influence on AB for food, possibly explaining the inconsistency in the literature. Fluctuations between a hedonic versus a health mindset might be strongest in restrained eaters, who have a conflicted relationship with food. We investigated the effect of mindset and dietary restraint on AB for food and food intake. We hypothesized that AB for food, as reflected in eye-movement measures and manual response latencies, as well as food intake, would be larger in the hedonic than in the health mindset, most strongly in participants scoring high on dietary restraint. Moreover, we expected a positive correlation between AB for food and food intake, especially in the hedonic mindset. We used short video clips to induce either a health or hedonic mindset. Subsequently, participants (n = 122) performed a modified additional singleton task with pictures of high-caloric food vs neutral pictures as irrelevant distractors. Next, food intake was measured in a bogus taste test. We found no evidence for an AB towards food, nor any moderation by either mindset or dietary restraint. Food intake tended to be higher for participants scoring higher on dietary restraint, but effects were not moderated by mindset. Response-latency based AB for food tended to correlate positively with food intake in the hedonic mindset. Taken together, our hypotheses regarding AB for food were largely not confirmed. We provide suggestions on how to improve upon the specific implementations of our AB task and mindset manipulation, to strengthen future research in this field.

Entropy of eye movement during rapid automatized naming.

Numerous studies have focused on the understanding of rapid automatized naming (RAN), which can be applied to predict reading abilities and developmental dyslexia in children. Eye tracking technique, characterizing the essential ocular activities, might have the feasibility to reveal the visual and cognitive features of RAN. However, traditional measures of eye movements ignore many dynamical details about the visual and cognitive processing of RAN, and are usually associated with the duration of time spent on some particular areas of interest, fixation counts, revisited fixation counts, saccadic velocities, or saccadic amplitudes. To cope with this drawback, we suggested an entropy-based method to measure eye movements for the first time, which first mapped eye movements during RAN in a time-series and then analyzed the time-series by a proper definition of entropy from the perspective of information theory. Our findings showed that the entropy was more sensitive to reflect small perturbation (e.g., rapid movements between focuses in the presence of skipping or omitting some stimulus during RAN) of eye movements, and thus gained better performance than traditional measures. We also verified that the entropy of eye movements significantly deceased with the age and the task complexity of RAN, and significantly correlated with traditional eye-movement measures [e.g., total time of naming (TTN)] and the RAN-related skills [e.g., selective attention (SA), cognitive speed, and visual-motor integration]. Our findings may bring some new insights into the understanding of both RAN and eye tracking technique itself.

A Meta-analysis on the Effect of Expertise on Eye Movements during Music Reading.

The current meta-analysis was conducted on 12 studies comparing the eye movements of expert versus non-expert musicians and attempted to determine which eye movement measures are expertise dependent during music reading. The total dataset of 61 comparisons was divided into four subsets, each concerning one eye-movement variable (i.e., fixation duration, number of fixations, saccade amplitude, and gaze duration). We used a variance estimation method to aggregate the effect sizes. The results support the robust finding of reduced fixation duration in expert musicians (Subset 1, g = -0.72). Due to low statistical power because of limited effect sizes, the results on the number of fixations, saccade amplitude, and gaze duration were not reliable. We conducted meta-regression analyses to determine potential moderators of the effect of expertise on eye movements (i.e., definition of experimental groups, type of musical task performed, type of musical material used or tempo control). Moderator analyses did not yield any reliable results. The need for consistency in the experimental methodology is discussed.

The database of eye-movement measures on words in Chinese reading

Eye movements are one of the most fundamental behaviors during reading. A growing number of Chinese reading studies have used eye-tracking techniques in the last two decades. The accumulated data provide a rich resource that can reflect the complex cognitive mechanisms underlying Chinese reading. This article reports a database of eye-movement measures of words during Chinese sentence reading. The database contains nine eye-movement measures of 8,551 Chinese words obtained from 1,718 participants across 57 Chinese sentence reading experiments. All data were collected in the same experimental environment and from homogenous participants, using the same protocols and parameters. This database enables researchers to test their theoretical or computational hypotheses concerning Chinese reading efficiently using a large number of words. The database can also indicate the processing difficulty of Chinese words during text reading, thus providing a way to control or manipulate the difficulty level of Chinese texts.