2,574 research outputs found
Reconstruction of eye movements during blinks
In eye movement research in reading, the amount of data plays a crucial role
for the validation of results. A methodological problem for the analysis of the
eye movement in reading are blinks, when readers close their eyes. Blinking
rate increases with increasing reading time, resulting in high data losses,
especially for older adults or reading impaired subjects. We present a method,
based on the symbolic sequence dynamics of the eye movements, that reconstructs
the horizontal position of the eyes while the reader blinks. The method makes
use of an observed fact that the movements of the eyes before closing or after
opening contain information about the eyes movements during blinks. Test
results indicate that our reconstruction method is superior to methods that use
simpler interpolation approaches. In addition, analyses of the reconstructed
data show no significant deviation from the usual behavior observed in readers
Aerospace medicine and biology: A continuing bibliography with indexes (supplement 359)
This bibliography lists 164 reports, articles and other documents introduced into the NASA Scientific and Technical Information System during Jan. 1992. Subject coverage includes: aerospace medicine and physiology, life support systems and man/system technology, protective clothing, exobiology and extraterrestrial life, planetary biology, and flight crew behavior and performance
Viewers change eye-blink rate by predicting narrative content
Eye blinks provoke a loss of visual information. However, we are not constantly making conscious decisions about the appropriate moment to blink. The presence or absence of eye blinks also denotes levels of attention. We presented three movies with the exact same narrative but different styles of editing and recorded participants' eye blinks. We found that moments of increased or decreased eye blinks by viewers coincided with the same content in the different movie styles. The moments of increased eye blinks corresponded to those when the actor leaves the scene and when the movie repeats the same action for a while. The moments of decreased eye blinks corresponded to actions where visual information was crucial to proper understanding of the scene presented. According to these results, viewers' attention is more related to narrative content than to the style of editing when watching movies
The Ocular Surface Control of Blinking, Tearing and Sensation
Thesis (Ph.D.) - Indiana University, Optometry, 2014Dry eye is a common condition that affects millions in the US and worldwide. It is considered to be a multifactorial disease of the tear film and ocular surface and is associated with symptoms of ocular discomfort and visual disturbance. Low blink rate has been identified as a potential risk factor for the development of dry eye because it can result in increased evaporative loss from the tear film. Failure of tear secretion has also been recognized as one of the main factors for dry eye development, characterized as low tear volume and slow tear turnover rate. Both factors in turn may lead to increased tear film hyperosmolarity and instability, which are considered core mechanisms of dry eye. In the natural condition, the ocular surface is mainly protected by blinking and tear secretion in that the newly secreted tears flow into the upper and lower meniscus and the blink spreads the new tear film from the meniscus to the ocular surface. Therefore, the ocular surface control over blinking and tear secretion is important in the etiology of the dry eye condition.
In this proposal, we develop a laboratory model using human subjects to test how input from the ocular surface affects both blinking and tear secretion. We hypothesize that ocular surface stimuli will activate corneal receptors to signal a high blink rate, reflex tear secretion and ocular sensations of discomfort. These probably act together for the purpose of preventing ocular damage. These results will help us to understand the manner in which the ocular surface responds to adverse stimuli, which may ultimately lead toward further development of treatments or methods in dry eye patients
Domain Generalization via Ensemble Stacking for Face Presentation Attack Detection
Face Presentation Attack Detection (PAD) plays a pivotal role in securing
face recognition systems against spoofing attacks. Although great progress has
been made in designing face PAD methods, developing a model that can generalize
well to unseen test domains remains a significant challenge. Moreover, due to
different types of spoofing attacks, creating a dataset with a sufficient
number of samples for training deep neural networks is a laborious task. This
work proposes a comprehensive solution that combines synthetic data generation
and deep ensemble learning to enhance the generalization capabilities of face
PAD. Specifically, synthetic data is generated by blending a static image with
spatiotemporal encoded images using alpha composition and video distillation.
This way, we simulate motion blur with varying alpha values, thereby generating
diverse subsets of synthetic data that contribute to a more enriched training
set. Furthermore, multiple base models are trained on each subset of synthetic
data using stacked ensemble learning. This allows the models to learn
complementary features and representations from different synthetic subsets.
The meta-features generated by the base models are used as input to a new model
called the meta-model. The latter combines the predictions from the base
models, leveraging their complementary information to better handle unseen
target domains and enhance the overall performance. Experimental results on
four datasets demonstrate low half total error rates (HTERs) on three benchmark
datasets: CASIA-MFSD (8.92%), MSU-MFSD (4.81%), and OULU-NPU (6.70%). The
approach shows potential for advancing presentation attack detection by
utilizing large-scale synthetic data and the meta-model
CATRA: Interactive Measuring and Modeling of Cataracts
We introduce an interactive method to assess cataracts in the human eye by crafting an optical solution that measures the perceptual impact of forward scattering on the foveal region. Current solutions rely on highly-trained clinicians to check the back scattering in the crystallin lens and test their predictions on visual acuity tests. Close-range parallax barriers create collimated beams of light to scan through sub-apertures, scattering light as it strikes a cataract. User feedback generates maps for opacity, attenuation, contrast and sub-aperture point-spread functions. The goal is to allow a general audience to operate a portable high-contrast light-field display to gain a meaningful understanding of their own visual conditions. User evaluations and validation with modified camera optics are performed. Compiled data is used to reconstruct the individual's cataract-affected view, offering a novel approach for capturing information for screening, diagnostic, and clinical analysis.Alfred P. Sloan Foundation (Research Fellowship)United States. Defense Advanced Research Projects Agency (Young Faculty Award
Short term effect of virtual reality on tear film stability and ocular discomfort
Virtual reality (VR) has been integrated and used with smartphones as one of the digital entertainments such as in gaming and movie streaming. With emergent of various VR brands in the market, it concerns the public on the possible side effects of VR on the ocular performance specifically on tear film stability and ocular discomfort. The purpose of this study was to compare the change on non-invasive keratograph tear break-up time (NIKBUT), tear meniscus height (TMH) before and after the use of VR for 30 minutes, and to measure the ocular discomfort after the use of VR quantitatively. Thirty-two subjects were recruited in this study and all the subjects were divided randomly into two groups; VR and laptop (used as a control) groups. Each subject needed to watch a movie for 30 minutes using the respective devices. The changes of tear film stability and ocular discomfort before and after the use of the devices were then compared and the results showed that there was no significant difference (p>0.05) after 30 minutes of the use. Comparison of the ocular parameters between the devices on post-watching activities was also not significant (p>0.05). Use of VR did not give any signs of dryness to the eyes and it can be used without any discomfort even after 30 minutes usage of the devices
- …