Assessing visual performance during intense luminance changes in virtual reality

Assessing visual performance during intense luminance changes in virtual reality

Decision letter: Visual and motor signatures of locomotion dynamically shape a population code for feature detection in Drosophila

Effects of luminence on the pattern visual evoked potential in multiple sclerosis

Technologies such as (AR) Augmented Reality &(VR) Virtual Reality, which provide immersive digital experiences, interactive environments, simulation, and engagement, have completely changed how we approach learning. However, in order to meet the huge demand in education, these technologies which are still in the emerging stage need to be heavily customized and heavily invested in. This thorough analysis seeks to contextualize the last few years of development of Virtual and Augmented Reality in the Education. For additional study, a total one thousand five hundred and thirty-six articles are chosen using text mining and theme analysis techniques. Based on earlier research on AR and VR in education, hypotheses were developed and are currently being processed and analysed to reveal the current development in literature via Augmented Reality and Virtual Reality, applications, benefits, and future directions. The findings show that wearable technology has contributed significantly to the exponential expansion in the use of Virtual and Augmented Reality in education in recent years. Results also highlight the need for faster adoption and customization of these technologies in educational institutions, based on secondary data. An increasing number of educational applications for the learning process are emerging as Virtual and Augmented Realityexp and quickly. It is advised that researchers stay up to date on the gaps in AR and VR’s Changeover to education &develop practical adaptation strategies to maximize the benefits of these technological development with significant developments in high-speed transmission and processing, AR &VR are developing as Display Platforms for Next Generation for more intimate human-digital interactions. Nonetheless, matching the extraordinary Human Vision Performance while keeping Near the Eye Display module tiny and lightweight presents unprecedented hurdles for optical engineering. Fortunately, new advances in Holographic Optical Elements HOEs and Lithography Enable Devices present novel approaches to overcoming these challenges in Virtual and Augmented Reality which would otherwise be problematic with traditional optics

The application of TDRSS in TT&C of launch vehicle can improve the coverage and transmission rate of TT&C link. But the transmission protocol based on fixed transmission rate can not ensure the stable TT&C link based on TDRSS. The adaptive transmission protocol proposed in this paper can adjust the transmission rate according to the real-time transmission status during the whole flight. According to the different types of rocket-borne subscriber terminals, the open loop adaptive transmission protocol and closed loop adaptive transmission protocol are designed, which can both keep the stable transmission and improve the transmission efficiency.

Stroboscopic training has repeatedly been shown to improve visual and visuomotor performance in sports. Although recent research suggests that stroboscopic vision puts a training stimulus to the central nervous system, the underlying mechanism how it affects motion perception and processing in the brain is still unknown. Twenty-six participants performed a computer-based simple reaction test in response to a visual motion stimulus under normal (baseline) and stroboscopic conditions (5Hz frequency, 40% duty cycle) (stroboscopic). A third condition under normal vision intermittently stopped the motion stimulus at the same frequency and duty cycle as in the stroboscopic condition. This condition controlled for the amount of visual motion information independent of the shutter glasses (screen shutter) and provided information about the effect of luminance changes induced by the stroboscopic eyewear. A 64-channel EEG was recorded to determine the amplitude and latency of the N2 component as a correlate of visual motion perception in the motion-sensitive visual area MT. Reaction time under stroboscopic conditions was significantly delayed when compared to both the baseline (p < 0.001) and screen shutter (p < 0.001) conditions. This was accompanied by a significantly prolonged N2 latency (p < 0.001) and lower N2 amplitude (p < 0.001) with the shutter glasses. There was no difference in reaction time or N2 amplitude/latency between the baseline and screen shutter condition (p ≥ 0.176). Stroboscopic eyewear delays the speed of visual motion perception and processing in the central nervous system and reduces the visuomotor reaction speed. This may form the neurophysiological basis for performance gains following stroboscopic training.

Using appropriate antipredatory responses is crucial for survival. While slowing down reduces the chances of being detected from distant predators, fleeing away is advantageous in front of an approaching predator. Whether appropriate responses depend on experience with moving objects is still an open question. To clarify whether adopting appropriate fleeing or freezing responses requires previous experience, we investigated responses of chicks naive to movement. When exposed to the moving cues mimicking an approaching predator (a rapidly expanding, looming stimulus), chicks displayed a fast escape response. In contrast, when presented with a distal threat (a small stimulus sweeping overhead) they decreased their speed, a maneuver useful to avoid detection. The fast expansion of the stimulus toward the subject, rather than its size per se or change in luminance, triggered the escape response. These results show that young animals, in the absence of previous experience, can use motion cues to select the appropriate responses to different threats. The adaptive needs of young preys are thus matched by spontaneous defensive mechanisms that do not require learning.

Background: Although both depressive symptoms and social isolation in relation to coronary heart disease have been studied previously, few have examined their joint effects on coronary atherosclerosis progression in women. Method: Among the women enrolled in the Stockholm Female Coronary Angiography Study, Sweden, between 1991 and 1994, 102 were evaluated for coronary atherosclerosis progression using a computer-assisted standardized assessment, repeated quantitative coronary angiographic documentation, of the mean luminal diameter change over 3 years in 10 predefined coronary segments. Depressive symptoms and social isolation were assessed by standard questionnaires. Results: Multivariable controlled mixed model ANOVAs revealed that women who were both depressed and socially isolated had the greatest disease progression: their absolute mean luminal diameter decreased by 0.18 mm [95% confidence interval (CI) = 0.11–0.24] and their percent narrowing was 5.5% (95% CI = 3.6–7.4), whereas in women who lacked both psychological risk factors, the mean luminal diameter decrease was 0.04 mm and their percent narrowing was 0.9%. These associations were independent of the baseline luminal diameter and standard risk factors, including age, smoking history, hypertension, and high-density lipoproteins. Conclusions:In women with coronary disease, depressive symptoms and social isolation in combination accelerated disease progression, suggesting a direct psychosocial effect on the atherosclerotic process. These findings provide an additional opportunity for therapeutic and preventive efforts against progression of coronary disease in women.

Model observers have been compared to human performance detecting low contrast signals in a variety of computer generated background including white noise, correlated noise, lumpy backgrounds, and two component noise. The purpose of the present paper is to extend this work by comparing a cumber of previously proposed model observers to human visual detection performance in real anatomic backgrounds. Human and model observer performance are compared as a function of increasing added white noise. Our results show that three of the four models are good predictors of human performance.

Although previous investigations have reported that changes in background luminance, stimulus contrast, and dioptric blur can each affect visual acuity independently, it has not been shown how these three variables interact to influence visual acuity. This is a particularly important issue if one is interested in predicting how individuals with different refractive characteristics will be able to perform acuity-based tasks in degraded visual environments with low background lighting and contrast levels. To investigate these relations, we conducted a series of experiments in which measurements of visual acuity were obtained for four subjects using Landolt C targets of varying contrast at several background luminances for levels of blur between 0 and 8 diopters (D). Our results show that visual acuity is significantly affected by all three factors, and that their effects are essentially additive. At all luminance and contrast levels, the reduction in visual acuity is greatest for dioptric blur up to 2.0 D, with a more gradual reduction in visual acuity for dioptric blur of greater than 2.0 D. At all blur and luminance levels, visual acuity decreases gradually for contrast levels down to 20%, and decreases sharply for lower contrast levels. Over the range of background luminances we tested (75.0 to 0.075 cd/m2), visual acuity decreases linearly with reductions in luminance. The additive effects of dioptric blur, contrast, and luminance provide a basis for predicting visual acuity-related task performance for individuals in different visual environments. For example, an individual with 6/6 (20/20) visual acuity under high luminance-high contrast conditions will fall to 6/18 (20/60) acuity for low luminance conditions and 6/30 (20/100) for low luminance-low contrast conditions. Similarly, an individual with an uncorrected visual acuity of 6/30 (20/100) under optimal conditions will fall to approximately 6/120 (20/400) under low luminance conditions and 6/240 (20/800) under low luminance-low contrast conditions.

BackgroundCeramic tiles are widely used in workplace environments, and their visual characteristics can influence users’ perceptual and cognitive experiences. However, research remains limited on how ceramic tile properties affect visual comfort, cognitive performance, and related neural responses.MethodThis study examines six common types of mass-produced ceramic tiles, employing virtual reality (VR) and electroencephalogram (EEG) technologies to evaluate visual comfort and cognitive performance. A 2 (patterned vs. non-patterned) × 3 (light-toned, medium-toned, dark-toned) factorial design was used to construct six immersive VR environments through 3D modeling. Data on visual comfort ratings, cognitive behavioral performance, and EEG responses were collected from participants in each environment. The effects of tile’s pattern and brightness on visual comfort, cognitive outcomes, and neural activity were analyzed.ResultThe findings indicate that environments with non-patterned and light-toned ceramic tiles received higher visual comfort ratings and elicited increased alpha wave power spectral density, reflecting positive emotional experiences. In terms of cognitive performance, the participants had shorter reaction durations in the environments of light-toned ceramic tiles and patterned ceramic tiles, and were negatively correlated with the beta wave power spectral density values.DiscussionThe results suggest that ceramic tile selection can be tailored to the functional needs of interior spaces. For instance, in relaxing settings such as lounges, tiles that enhance alpha-wave activity may be preferable, while in workspaces requiring high cognitive engagement--such as studios, meeting rooms, or offices--tiles that promote moderate beta-wave activity may be more suitable. This study provides valuable insights and evaluation methods for interior and ceramic tile designers, especially for design of Chinese region.

Conducted at the Office of Mine Safety and Health Research laboratory of the National Institute for Occupational Safety and Health (NIOSH), this experiment is part of ongoing mine illumination research designed to explore the benefits of solid state lighting technologies when applied to the underground mining industry. This experiment involves the comparative evaluation of cap lamps with similar spectral power distributions, focusing on the electrical and battery discharge characteristics, with a secondary objective being exploring the benefits gained through alternative light beam distributions. NIOSH researchers conducted the investigation by comparing three commercially available LED cap lamps and a NIOSH prototype cap lamp at varying power settings. Visual performance for the detection of hazards was quantified by recording times of detection for finding rotating targets in the peripheral field of view and objects representing trip and fall hazards on the ground. Results show that the NIOSH prototype improved the ability to perceive objects in the visual field by improving peripheral motion detection times by as much as 79.5%, and ground hazard detection times by as much as 194.1%.

The fast growth of virtual reality (VR) and augmented reality (AR) head-mounted displays provides a new medium for interactive visualisations and visual analytics. Presence is the experience of consciousness within extended reality, and it has the potential to increase task performance. This project studies the impact that a sense of presence has on data visualisation performance and user experience under AR and VR conditions. A within-subjects design recruited 38 participants to complete interactive visualisation tasks within the novel immersive data analytics system for genomic data in AR and VR, and measured speed, accuracy, preference, presence, and user satisfaction. Open-ended user experience responses were also collected. The results implied that VR was more conducive to efficiency, effectiveness, and user experience as well as offering insight into possible cognitive load benefits for VR users.

The effects of the presence of others during a rowing exercise in a virtual reality environment

Many investigators are currently developing models to predict human performance in detecting a signal embedded in complex backgrounds. A common figure of merit for model performance is d', an index of detectability that can be mathematically related to the proportion correct (Pc) when the responses of the model are Gaussian distributed and statistically independent. However, in many multiple-alternative forced-choice (MAFC) detection tasks, the target appears in one of M different locations within an image. If the image contains slow spatially varying luminance changes (low-pass noise), the pixel luminance values at the possible signal locations are correlated and therefore the model/human responses to the different locations might also be correlated. We investigate the effect of response correlations on model performance and compare different figures of merit for these conditions. Our results show that use of the standard d' index of detectability assuming statistical independence can lead to erroneous underestimates of Pc and misleading comparisons of models. We introduce a novel figure of merit d'(r) that takes into account response correlations and can be used to accurately estimate Pc. Furthermore, we show that d'(r) can be readily related to the standard index of detectability d' by d'(r) = d'/square root of (1 - r), where r is the correlation between the responses in any MAFC detection task. We illustrate the use of the theory by computing figures of merit for two linear models detecting a signal in one of four locations within medical image backgrounds.