Average Pupil Diameter Research Articles

Evaluation of Cognitive Load Differences between Elderly and Young Pedestrians at the Signalised Intersection

The pedestrian cognitive load has an important effect on the pedestrian crossing decision making. Compared with young adults, old people are characterised by declining physical function and slower reaction ability, which makes them prone to traffic accidents when crossing the street. This study aims to compare the visual information-mental load correlation between elderly and young adults waiting at the signalised intersections and evaluate their cognitive load conditions. Therefore, two signalised intersections with different traffic scenes in the Nan’an District, Chongqing, China were selected. The eye-tracking, electrocardiographic and electrodermal activity data of young and old pedestrians were collected using eye-tracking and physiological instruments. The visual indexes (the total duration of fixations, the number of fixations, the average pupil diameter changing rate, the number of saccades, the average peak speed of saccades, the average amplitude of saccades and the total amplitude of saccades) and physiological indicators (the average growth rate of heart rate, the time-domain analysis indicator of HRV and HRV frequency domain analysis indicators, electrodermal response amplitude and rise time of the EDR amp.) were taken as inputs and outputs parameters, respectively. Then, the comprehensive cognitive load evaluation model for pedestrians was constructed when waiting to cross the street based on the data envelopment analysis method. And the cognitive load characteristic differences between the young adults and the elderly were compared. The results show that in the same crossing scene, compared with the young pedestrian, the elder pedestrian exhibited lower overall perceptual efficiency, lower fixation durations and higher cognitive loads. These results can provide certain references on improving the street crossing safety for the elderly pedestrian.

Effects of different audiovisual landscapes in bamboo forest space on physical and mental restorative potential of university students: based on eye-tracking experiments

With its unique audiovisual environment, bamboo forest spaces serve as natural sanctuaries for urban residents, offering significant restorative effects by reducing physical and mental stress and alleviating fatigue. This promotes the vigorous development of outdoor recreation activities. To further explore the restorative effects of bamboo forest space on people's audiovisual perceptual aspects. In this study, we conducted field research in the Southern Sichuan Bamboo Sea, collecting audiovisual materials from four types of bamboo forest spaces: pathway type, cultural type, ornamental type, and recreational. These spatial photographs were combined with three types of soundscapes (silent, background, and background + wind-blown bamboo sound). Eye tracking experiments were utilized to investigate the physical and mental restorative effects of these different audiovisual features on college students. The results showed that in the visual aspect, the visual restorative properties of recreational-type and ornamental-type bamboo spaces were better than those of pathway type and cultural-type spaces; in the auditory aspect, the sounds of wind-blown bamboo, flowing water, and chirping birds in the bamboo forest significantly enhanced the subjective restorative properties of the bamboo forest space, reducing the number of fixations and the average pupil diameter. In addition, this paper found that the soundscape guided people's visual attention, with the wind-blown bamboo sound increasing focus on natural elements, and the extensibility of the bamboo forest space was positively correlated with the number of fixations, while fascination was negatively correlated with the average saccade amplitude. These findings provide insights for the optimized design of audiovisual restorative environments in bamboo forest space in the future.

Pupillometry as a biomarker of postural control: Deep-learning models reveal side-specific pupillary responses to increased intensity of balance tasks.

Pupillometry has been used in the studies of postural control to assess cognitive load during dual tasks, but its response to increased balance task intensity has not been investigated. Furthermore, it is unknown whether side-specific changes in pupil diameter occur with more demanding balance tasks providing additional insights into postural control. The two aims of this study were to analyze differences in steady-state pupil diameter between balance tasks with increased intensity and to determine whether there are side-specific changes. Forty-eight healthy subjects performed parallel and left and right one-legged stances on a force plate with and without foam with right and left pupil diameters measured with a mobile infrared eye-tracker. Differences between balance tasks in parameters (average pupil diameter of each eye, average of both pupil diameters and the difference between the left and right pupil diameter) were analyzed using a two-way repeated measures analysis of variance, and deep learning neural network models were used to investigate how pupillometry predicted each balance task. The pupil diameter of the left eye, the average pupil diameter of both eyes and the difference in pupil diameters increased statistically significantly from simpler to more demanding balance tasks, with this being more pronounced for the left eye. The deep learning neural network models revealed side-specific changes in pupil diameter with more demanding balance tasks. This study confirms pupillary responses to increased intensity of balance task and indicates side-specific pupil responses that could be related to task-specific involvement of higher levels of postural control.

Research on the restorative benefits of sky gardens in high-rise buildings based on wearable biosensors and subjective evaluations

BackgroundThe design of sky gardens in high-rise buildings to promote health has recently attracted increased attention. However, little is known about the specific physiologically and psychologically restorative benefits of sky gardens. MethodThis article defined sky garden types according to five indicators in three dimensions based on the characteristics of the high-rise buildings where sky gardens are located: plaza-park, rest-stay and move-pass sky gardens. Typical sky gardens of each type were selected for the subsequent experiment. Thirty-six participants experienced 12 typical case scenarios (432 pictures), and data were collected on physiological responses (skin conductance resistance, SCR; heart rate variability, HRV; electroencephalogram, EEG; and eye movement) and psychological evaluations (emotional valence & arousal self-esteem scale, perceived restrictiveness scale) during the sky garden spatial experience. ResultsThere are significant differences in plaza-park, rest-stay and move-pass type sky gardens, especially in the internal spatial characteristics (size scale, shape index, and elementary richness). The plaza-park sky gardens had better restorative outcomes in visual-physiological (average pupil diameter, average blink count), emotional valence and restrictiveness components of being away, fascination, and coherence. The rest-stay sky gardens had better restorative effects on SCR, HRV, emotional arousal, and compatibility. The move-pass sky gardens had the greatest restorative benefits in the average saccade count. ConclusionsSky gardens in high-rises impact people's physical and psychosocial well-being. The restorative qualities of the three types of sky gardens differ based on their spatial heterogeneity, with large-scale sky gardens, diverse natural landscapes, public facilities, and high void-to-solid ratios having greater restorative potential.

Pupillary correlates of individual differences in n-back task performance.

We used pupillometry during a 2-back task to examine individual differences in the intensity and consistency of attention and their relative role in a working memory task. We used sensitivity, or the ability to distinguish targets (2-back matches) and nontargets, as the measure of task performance; task-evoked pupillary responses (TEPRs) as the measure of attentional intensity; and intraindividual pretrial pupil variability as the measure of attentional consistency. TEPRs were greater on target trials compared with nontarget trials, although there was no difference in TEPR magnitude when participants answered correctly or incorrectly to targets. Importantly, this effect interacted with performance: high performers showed a greater separation in their TEPRs between targets and nontargets, whereas there was little difference for low performers. Further, in regression analysis, larger TEPRs on target trials predicted better performance, whereas larger TEPRs on nontarget trials predicted worse performance. Sensitivity positively correlated with average pretrial pupil diameter and negatively correlated with intraindividual variability in pretrial pupil diameter. Overall, we found evidence that both attentional intensity (TEPRs) and consistency (pretrial pupil variation) predict performance on an n-back working memory task.

Effects of Exercise Habits and Gender on Sports e-Learning Behavior: Evidence from an Eye-Tracking Study.

In the post-epidemic era, an increasing number of individuals were accustomed to learning sports and physical activity knowledge online for fitness and health demands. However, most previous studies have examined the influence of e-learning materials and resources on learners and have neglected intrinsic factors such as experience and physiological characteristics. Therefore, we conducted a study to investigate the effect of exercise habits and gender on sports e-learning behavior via eye-tracking technology. We recruited a sample of 60 undergraduate students (mean age = 19.6) from a university in Nanjing, China. They were randomly assigned into 4 groups based on 2 genders × 2 exercise habits. Their gaze behavior was collected by an eye-tracking device during the experiment. The cognitive Load Test and Learning Effect Test were conducted at the end of the individual experiment. (1) Compared to the non-exercise habit group, the exercise habit group had a higher fixation count (P<0.05), a shorter average fixation duration (P<0.05), a smaller average pupil diameter (P<0.05), and a lower subjective cognitive load (P<0.05) and better learning outcome (P<0.05). (2) Male participants showed a greater tendency to process information from the video area of interest (AOIs), and had lower subjective cognitive load (P < 0.05) and better learning outcomes (P < 0.05). (3) There was no interaction effect between exercise habits and gender for any of the indicators (P > 0.05). Our results indicate that exercise habits effectively enhance sports e-learning outcomes and reduce cognitive load. The exercise habits group showed significant improvements in fixation counts, average fixation duration, and average pupil diameter. Furthermore, male subjects exhibited superior learning outcomes, experienced lower cognitive load, and demonstrated greater attentiveness to dynamic visual information. These conclusions are expected to improve sports e-learning success and address educational inequality.

Development of performance and learning rate evaluation models in robot-assisted surgery using electroencephalography and eye-tracking

The existing performance evaluation methods in robot-assisted surgery (RAS) are mainly subjective, costly, and affected by shortcomings such as the inconsistency of results and dependency on the raters’ opinions. The aim of this study was to develop models for an objective evaluation of performance and rate of learning RAS skills while practicing surgical simulator tasks. The electroencephalogram (EEG) and eye-tracking data were recorded from 26 subjects while performing Tubes, Suture Sponge, and Dots and Needles tasks. Performance scores were generated by the simulator program. The functional brain networks were extracted using EEG data and coherence analysis. Then these networks, along with community detection analysis, facilitated the extraction of average search information and average temporal flexibility features at 21 Brodmann areas (BA) and four band frequencies. Twelve eye-tracking features were extracted and used to develop linear random intercept models for performance evaluation and multivariate linear regression models for the evaluation of the learning rate. Results showed that subject-wise standardization of features improved the R2 of the models. Average pupil diameter and rate of saccade were associated with performance in the Tubes task (multivariate analysis; p-value = 0.01 and p-value = 0.04, respectively). Entropy of pupil diameter was associated with performance in Dots and Needles task (multivariate analysis; p-value = 0.01). Average temporal flexibility and search information in several BAs and band frequencies were associated with performance and rate of learning. The models may be used to objectify performance and learning rate evaluation in RAS once validated with a broader sample size and tasks.

Coordination analysis of layout and visual color difference in responsive web design based on PS software

Abstract In the new era of the “Internet +” economic background, people's aesthetic standards continue to improve, and there are higher requirements for web design work. This paper is based on the Bootstrap framework to design responsive web pages and utilizes the grid system in the Bootstrap framework to enable the automatic layout of web pages. Then PS software technology is applied as the core technology in responsive web page design, and PS software is used to detect and adjust the optimization of responsive web page layout and visual chromatic aberration so as to present users with coordinated, beautiful, and easy-to-operate responsive web pages. By designing eye movement experiments to collect and analyze the eye movement data of the subjects when browsing web pages, the average pupil diameter of the users showed a significant difference in browsing different web pages (P=0.014&lt;0.05). The web pages designed by PS software were more appealing to the users and increased their interest in browsing web pages. The results of the psychological level showed that the subject users found the web pages created by applying PS software more impressive than ordinary web pages (P=0.004&lt;0.01). This paper provides a useful guide for web page designers to enhance the visual experience for users when browsing web pages.

Оценка факторов риска развития интраоперационного синдрома девиации инфузионных потоков с учетом анатомо-топографических особенностей переднего отрезка

Relevance. Despite continuous improvement in cataract surgery technology, intraoperative fluid misdirection syndrome remains an underestimated problem. Purpose. To evaluate intraoperative fluid misdirection syndrome clinical manifestation in patients with pseudoexfoliation syndrome (PXS) and without it; to assess intraoperative fluid misdirection syndrome risk factors according to anatomical and topographical features of anterior segment. Material and methods. There were two groups of patients who underwent phacoemulsification in the prospective study. Study group (50 eyes) included patients with complicated cataract, PXS and drug-induced mydriasis less than 6 mm. Control group (50 eyes) included patients with senile cataract, no PXS and drug-induced mydriasis more than 6 mm were enrolled in the control group. Clinical examination of patients included optical biometry, pupillometry using rotational Scheimpflug imaging, ultrasound biomicroscopy for evaluation of iris thickness and sectional area of posterior chamber under drug-induced mydriasis. Results. The average pupil diameter in 1 hour after instillation of mydriatics was 5.46±0.46 mm in the study group and 6.6±0.43 mm in the control group. The sectional area of posterior chamber was 0.67±0.28 mm² and iris thickness – 0.53±0.05 mm in the study group. The sectional area of posterior chamber was 0.43±0.15 mm² and iris thickness – 0.64±0.07 mm in the control group. The results revealed positive correlation between pupil diameter and iris thickness, and negative correlation between pupil diameter, iris thickness and sectional area of posterior chamber. Lens floaters were determined after phacoemulsification in 9 eyes (18%) in the study group and in 3 eyes (6%) in the control group. The results showed statistically significant difference between groups (p≤0.05). Conclusion. Lens floaters in the retrolental space as one of the main manifestations of the intraoperative fluid misdirection syndrome were observed in 18% patients of study group and in 6% patients of control group (p≤0.05). Combination of PXS and drug-induced mydriasis less than 6 mm is considered to be the predictive factor of intraoperative fluid misdirection syndrome. Key words: intraoperative fluid misdirection syndrome, pseudoexfoliation syndrome, anterior vitreous face

Pupillometry as a marker of arousal and in relation to cognition and cortical dynamics in Alzheimer’s disease

AbstractBackgroundPupil dilation is an established measure of noradrenergic activity. Cortical EEG alpha power, a measure of attentional engagement, can be recorded simultaneously with pupillometry. Dysfunction in the noradrenergic system in Alzheimer’s disease (AD), contributes to the attentional deficits seen in patients. We investigated whether pupillometry recorded at rest can be used to show reduced noradrenergic activity in AD and how this relates to cortical dynamics.MethodWe recorded simultaneous EEG and pupillometry during 5min of eyes‐open resting‐state in 28 AD patients and 22 age‐matched controls (HC). Pupil dilations – peaks of both pupil diameter and velocity – were identified (Fig. 1A/B). Average pupil diameter and velocity were calculated across all dilations, and compared between groups (Fig. 1 C/D). We plotted EEG power spectra for the 2s pupil dilation‐centred epochs (Fig. 2A). The frequency at which there was the greatest power within the alpha band – the peak alpha frequency (PAF) – was calculated for each individual and compared across groups (Fig. 2B). We then measured the alpha power during the pupil‐dilation epochs and looked at the relationship with the pupils (Fig. 3).ResultIn HCs, the mean pupil dilations – peaks in diameter and peaks in velocity – were greater than in AD; t = ‐2.62 p = 0.01 and t = ‐2.26 p = 0.03, respectively (Fig. 1C/D). Power spectra for the 2s pupil dilation‐centred epochs showed patients’ PAF was significantly lower than HC’s; t = 2.92 p&lt;0.01 (Fig. 2). There was a corresponding peak in alpha power associated with the pupil dilations, in both groups. Regarding peaks in pupil diameter, the alpha power peaked approximately 0.5sec earlier (Fig. 3A). Regarding peaks in pupil velocity, the alpha power peaked simultaneously with the pupils (Fig. 3B).ConclusionThere is a reduction in size and velocity of spontaneous pupil dilations in AD. EEG alpha is shifted to lower frequencies in AD. There is a preserved relationship between pupil dilations and alpha peaks in AD. Pupillometry offers a means of measuring noradrenergic dysfunction in AD that relates to altered cortical dynamics.

Visual attention predictive model of built colonial heritage based on visual behaviour and subjective evaluation

Although physiological measurements, subjective evaluation and other methods have been applied to visual attention research, architects still lack a systematic quantitative classification method when assessing the visual attention to built colonial heritage. This study aimed to investigate the relationship between people’s visual behaviour and subjective evaluation when observing built colonial heritage and to construct a prediction model based on eye-movement metrics and subjective evaluation indicators to distinguish the visual attention to built colonial heritage. This study recorded data from 54 participants while observing five scenes of built colonial heritage, and the results showed that participants had different visual behaviours and subjective evaluations when viewing built colonial heritage in different scenes. And visual attention to built colonial heritage was negatively correlated with the average saccades peak velocity and average saccades amplitude and positively correlated with the average pupil diameter; visual attention was correlated with 12 subjective evaluation indicators. The eye-movement metrics and subjective evaluation indicators with correlation to visual attention were used as input variables to construct a prediction model of visual attention to built colonial heritage based on the BP neural network. Different built colonial heritage’s low, middle and high visual attention were identified with high accuracy (74.46%). This quantitative method can help architects to measure the visual attention to built colonial heritage to develop conservation and renewal strategies.

Sensor-based Stress Level Monitoring: An Exploratory Study

Stress is a common concern in modern workplaces. However, traditional stress measurements such as selfreported questionnaires have limited application in real-world settings. In this exploratory study, we collected physiological signals via a wristband and an eye tracker from five participants while they were executing a stress-inducing task. Our mixed-effect model revealed that several physiological responses, including electrodermal activity, skin temperature, and average pupil diameter, can be used as indicators of perceived stress levels. Our findings suggest the potential of using physiological sensors to monitor individuals’ perceived stress in real-world scenarios and thus facilitate workplace stress management and intervention.

Quantitative Model Study of the Psychological Recovery Benefit of Landscape Environment Based on Eye Movement Tracking Technology

From the perspective of landscape and human health, we use the Self-Rating Restoration Scale (SRRS) as a tool to explore the mental health restoration benefits brought by a landscape environment to individuals and explore the characteristics of individual movement behavior when viewing the landscape through the eye movement tracking technology. We selected average blink duration, average gaze length, average saccade amplitude, blink number, number of fixation points, saccade number, and average pupil diameter as experimental indicators for data monitoring. Based on the eye movement heat map obtained by data visualization processing and the results of correlation analysis, we summarized the eye movement behavior characteristics of individuals when viewing the restorative landscape. We try to construct a quantitative evaluation model of the landscape mental recovery benefit with the objective eye movement index as the independent variable through the method of curve estimation. The study results show that individual eye movement behavior is related to the landscape type and the level of psychological recovery is also different. (1)The more singular that the constituent elements are, the more widespread and concentrated the regional distribution of individual attention areas, and the relative psychological recovery benefit is relatively weak. The more complex that the constituent elements are, the more scattered and smaller the individual interest area, and the psychological recovery benefit is better. Brightly colored, dynamic landscapes are easier to form areas of interest to improve the psychological response to the human body. (2) The psychological recovery benefit of the landscape is directly proportional to the changing trend of the average blink duration, number of fixation points, and number of saccades and is inversely proportional to the changing trend of the average gaze length. (3) The objective eye movement index of average blink duration can quantitatively predict the psychological recovery benefit value of the landscape environment. The number of fixation points, the number of saccades, and the average fixation length could predict the psychological recovery benefits of the landscape, while the other indicators had no prediction effect.

Pupillometric parameters of alertness during unpredictable but not predictable smooth pursuit neck torsion test are altered in patients with neck pain disorders: a cross-sectional study

Despite commonly investigated predictable smooth-pursuit neck-torsion tasks (SPNT) in neck pain patients, unpredictable conditions have been seldom investigated but are indicative of preserved oculomotor functions during neck torsion. Although not previously studied, some speculations about compensatory cognitive mechanisms such as increased phasic alertness during unpredictable tasks were suggested. The aim of this study was to investigate eye movement accuracy and pupillometric responses during predictable and unpredictable SPNT test in neck pain patients and asymptomatic controls. Eye movements (gain and SPNT-difference) and pupillometry indicative of tonic (average and relative pupil diameter) and phasic (index of cognitive activity-ICA) alertness were measured in 28 idiopathic neck pain patients and 30 asymptomatic individuals using infrared video-oculography during predictable and unpredictable SPNT test. Gain in unpredictable SPNT test was lower as compared to predictable tasks and presented with similar levels in neutral and neck torsion positions, but not in the predictable SPNT test. ICA was lower during neutral position in all tasks in patients as compared to control group but increased during neck torsion positions in unpredictable tasks. Relative pupil diameters presented with no differences between the groups or neck positions, but the opposite was observed for average pupil diameter. Higher ICA indicates an increase in phasic alertness in neck pain patients despite no alterations in oculomotor control during SPNT test. This is the first study to indicate cognitive deficits in oculomotor task in neck pain patients. The latter could negatively affect other tasks where additional cognitive resources must be involved.

Long-Term Clinical and Functional Results of High-Grade Myopia Correction by Intrastromal Implantation of the MyoRing Ring with Femtolaser Support

Purpose: Analysis of remote clinical functional results of high myopia correction in patients with thin cornea by method of intrastromal MyoRing implantation with Femtolaser assistance.Materials and methods. 22 eyes of 22 patients were included into investigation, the мean age of patients was 30.20 ± 5.37 (from 24 to 40) years. Mean spherical equivalent (SE) of refraction was –11.52 ± 1.96 D, cylindrical component of refraction was –2.04 ± 1.64 D. Minimal pachymetry index in center was 491.6 ± 20.0 mkm. Corneal hysteresis (CH) was 8.60 ± 1.19 mm Hg. The average pupil diameter in mesopic conditions was 5.60 ± 0.23 mm. All patients had a history of mild amblyopia. Period of control in average 2 years.Results. In 2 years after the surgery uncorrected visual acuity was 0.60 ± 1.22, corrected visual acuity 0.70 ± 0.20. Mean spherical equivalent (SE) of refraction was 0.61 ± 1.43 D, cylindrical component of refraction was –0.13 ± 0.50 D. Predictability of SE within ±0.5 D was 84 %, ±1.0 — 84 %. Index of safety was 1.16, index of efficacy — 1.0. CH was 9.50 ± 0.03 mm Hg. Mean pachymetry at center after the surgery did not change statistically significant in comparison with initial data (p = 1.00).Conclusion. MyoRing implantation is an effective and safe method, it provides: refraction spherical component correction, astigmatism correction and CH increase (p = 0.01).

The Identification of Individualized Eye Tracking Metrics in VR Using Data Driven Iterative- Adaptive Algorithm

Eye tracking metrics provide information about cognitive function and basic oculomotor characteristics. There have been many studies analyzing eye tracking signals using different algorithms. However, these algorithms generally are based on the initial setting parameter. This might cause the subjective interpretation of eye tracking analysis. The main aim of this study was to develop a data-driven algorithm to detect fixations and saccades without any subjective settings. Three subjects were included in this study. Eye tracking signal was acquired with the VIVE Pro Eye in virtual reality (VR) environment while subjects were reading a paragraph. The algorithms based on the calculation of threshold were employed to calculate eye metrics including total fixation duration, total fixation number, total saccades number and average pupil diameter. The proposed algorithm, which is based on calculating the initial threshold, based on mean, and standard deviation of eye tracking signal within experiment duration, gave the same results obtained adaptive filtering reported in literature (average fixation duration for three subjects= 11515 ms ± 6951.2, average fixation count for three subjects= 17.33 ± 4.16). On the other hand, our proposed algorithm didn’t use any certain objective parameter as like adaptive filtering. As a conclusion, VIVE Pro Eye may be utilized as an eye movement assessment device, and, the suggested approach might be utilized to analyze objective eye tracking metrics.

Comparative analysis of light environment perception, eye movement and physiology in university professional classroom based on virtual reality experiment

In this study, virtual reality technology was used to simulate the virtual scene of three common light environment forms of professional classrooms in universities. The experimental results show that people’s environmental perception is related to the average pupil diameter, saccade frequency, high frequency/low frequency (LF/HF) and skin conductance change rate in a combined light environment; moreover, when the colour temperature is 4500 K, the space is brighter, more spacious, more relaxed and the willingness to learn is stronger. In the range of 22.4°C–25°C, temperature does not affect people’s perception of the warm feeling of the light environment, while the light colour temperature has a greater impact on people’s perception of the warm feeling. The lower the light colour temperature is, the warmer people feel subjectively. However, people’s eye movement behaviour and physiological system data have no obvious perception of colour temperature changes. Indoor noise affects the indoor brightness perception to some extent. In the range of 43–46.9 dB, with the increase of noise value, the evaluation score of people’s brightness perception basically increases. In terms of learning psychological state, the more comfortable the light environment is, the stronger the willingness to learn and the higher the learning enthusiasm.

An eye-tracking study on visual perception of vegetation permeability in virtual reality forest exposure.

Previous studies have confirmed the significant effects of single forest stand attributes, such as forest type (FT), understory vegetation cover (UVC), and understory vegetation height (UVH) on visitors' visual perception. However, rarely study has yet clearly determined the relationship between vegetation permeability and visual perception, while the former is formed by the interaction of multiple forest stand attributes (i.e., FT, UVC, UVH). Based on a mixed factor matrix of FT (i.e., coniferous forests and broadleaf), UVC level (i.e., 10, 60, and 100%), and UVH level (0.1, 1, and 3 m), the study creates 18 immersive virtual forest videos with different stand attributes. Virtual reality eye-tracking technology and questionnaires are used to collect visual perception data from viewing virtual forest videos. The study finds that vegetation permeability which is formed by the interaction effect of canopy density (i.e., FT) and understory density (i.e., UVC, UVH), significantly affects participant's visual perception: in terms of visual physiology characteristics, pupil size is significantly negatively correlated with vegetation permeability when participants are viewing virtual reality forest; in terms of visual psychological characteristics, the understory density formed by the interaction of UVC and UVH has a significant impact on visual attractiveness and perceived safety and the impact in which understory density is significantly negatively correlated with perceived safety. Apart from these, the study finds a significant negative correlation between average pupil diameter and perceived safety when participants are viewing virtual reality forests. The findings may be beneficial for the maintenance and management of forest parks, as well as provide insights into similar studies to explore urban public green spaces.

Do executive function performance, gaze behavior, and pupil size change during incremental acute physical exercise?

Several studies have investigated the interaction between acute physical exercise and cognitive performance. However, few studies have investigated this issue during acute high-intensity exercise. In the present study, we evaluated executive functions (EFs) during incremental exercise in three different intensities [below lactate threshold (LT), at LT, and above LT], measuring EFs performance, gaze behavior, and pupil diameter. Twenty subjects were familiarized with the EFs test and participated in a graded maximal exercise test on a cycle ergometer on the first visit. On the second visit, they performed the EFs task at rest and while exercising at three different intensities using mobile eye-tracking glasses. Our results showed that the psychophysiological measures differed between the conditions. Regarding EFs performance, during exercise above LT, the subjects showed worse accuracy when compared with rest (p < .001) and below LT (p < .001). In addition, the response time (RT) at LT and above LT was shorter than in the rest condition (p < .050). Further, RT was faster (p=.002) in the above LT than in the below LT condition. In addition, the gaze behavior measures indicated that exercise, independently of the intensity, improves the number of fixations with shorter fixation durations compared to the rest condition (p < .050). Additionally, we found no significant differences in average and peak pupil diameter between conditions. In conclusion, exercise at LT improves the EFs performance while exercising above LT worsens EFs performance. However, there were no significant differences in average and peak pupil diameter between conditions.

Smartphone video nystagmography using convolutional neural networks: ConVNG

BackgroundEye movement abnormalities are commonplace in neurological disorders. However, unaided eye movement assessments lack granularity. Although videooculography (VOG) improves diagnostic accuracy, resource intensiveness precludes its broad use. To bridge this care gap, we here validate a framework for smartphone video-based nystagmography capitalizing on recent computer vision advances.MethodsA convolutional neural network was fine-tuned for pupil tracking using > 550 annotated frames: ConVNG. In a cross-sectional approach, slow-phase velocity of optokinetic nystagmus was calculated in 10 subjects using ConVNG and VOG. Equivalence of accuracy and precision was assessed using the “two one-sample t-test” (TOST) and Bayesian interval-null approaches. ConVNG was systematically compared to OpenFace and MediaPipe as computer vision (CV) benchmarks for gaze estimation.ResultsConVNG tracking accuracy reached 9–15% of an average pupil diameter. In a fully independent clinical video dataset, ConVNG robustly detected pupil keypoints (median prediction confidence 0.85). SPV measurement accuracy was equivalent to VOG (TOST p < 0.017; Bayes factors (BF) > 24). ConVNG, but not MediaPipe, achieved equivalence to VOG in all SPV calculations. Median precision was 0.30°/s for ConVNG, 0.7°/s for MediaPipe and 0.12°/s for VOG. ConVNG precision was significantly higher than MediaPipe in vertical planes, but both algorithms’ precision was inferior to VOG.ConclusionsConVNG enables offline smartphone video nystagmography with an accuracy comparable to VOG and significantly higher precision than MediaPipe, a benchmark computer vision application for gaze estimation. This serves as a blueprint for highly accessible tools with potential to accelerate progress toward precise and personalized Medicine.