Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
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Showing 1 to 20 of 48 for “"contrast sensitivity"”.
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Dynamic contrast sensitivity: methods and measurements
… At each of two different testing sessions, the contrast sensitivities of 60 undergraduate psychology majors were measured at a static, 25 deg/sec, and 50 deg/sec target movement condition. The results indicate that as target velocity was increased, contrast sensitivity decreased at middle and …
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Contrast sensitivity and emotion recognition across the menstrual cycle
… of this cyclic variation, experiment 1 measured contrast sensitivity across the menstrual cycles of naturally cycling women and women using combined-oral contraception, and also in males. Findings showed no difference in contrast sensitivity between male and female participants, where no …
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Contrast Sensitivity to One- and Two-Dimensional Luminance Patterns
Contrast sensitivities to one- and two-dimensional luminance patterns were compared in a two-alternative forced choice (2AFC) experiment. Space-averaged luminance was also manipulated. Statistical analyses revealed a main effect of stimulus dimension (p < .05) and no effect of space-averaged …
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The Effects Of Stimulus Motion On Contrast Sensitivity: Dynamic Sensi
… the targets employed in most SVA testing (high contrast, stationary letters) are an insufficient analog to actual targets encountered in everyday activities, which are often in motion and/or of less-than-perfect contrast. In addition, the size-threshold methodology typically used to measure SVA …
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The effects of target vibration on the human contrast sensitivity function
… effects of vibration on visual acuity. The human contrast sensitivity function (CSF) has also been studied extensively as a predictor of visual performance under real-world conditions. However, no previous studies have combined the two lines of research and examined the effect of vibration on the …
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The effects of target orientation on the dynamic contrast sensitivity function
… of target orientation on visual acuity. The contrast sensitivity function (CSF) also has been studied as a predictor of visual performance under dynamic conditions. However, no previous studies have combined these areas of research and examined the effect of target orientation on the Dynamic …
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Trait-Based Individual Differences on Discomfort Glare Rating Responses and Related Visual Contrast Sensitivity
… glare subjective responses as well as the actual contrast sensitivity when exposed to the same manipulated glare condition. In addition, the relationship between the glare subjective responses and actual contrast sensitivity was investigated. To examine the trait-based individual differences, the …
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Contrast sensitivity and glare: new measurement techniques and the visual consequences of wearing head-mounted displays
… thesis was to evaluate the performance of the contrast sensitivity clock (CSC), a new screening device for measuring contrast sensitivity (CS) and glare. This device allows CS without glare, with glare and disability glare scores to be recorded. After initial data collection the design of the …
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Do colored overlays improve reading?: a test of the Irlen effect
… and, in particular, to assess the role visual contrast sensitivity may play in this treatment and in reading problems in general. Arguments both supporting and refuting the validity of the Irlen technique of using colored overlays and lenses as a treatment for reading problems are reviewed. …
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MRI Measures of Neurodegeneration as Biomarkers of Alzheimer's Disease
… as biomarkers of AD. In the first chapter, the sensitivity of cross-sectional MRI biomarkers to neurodegenerative changes is evaluated in AD patients and in patients with a diagnosis of mild cognitive impairment (MCI), a prodromal stage of AD. The results in Chapter 1 suggest that …
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Psychophysical aspects of clinical perimetry: studies in ageing and disease
Purpose: Measurement of contrast sensitivity (CS) across the visual field (VF) is critical in assessing the integrity of the visual system. Questions that remain to be addressed in the use of conventional clinical perimetry techniques include: How does CS change with age across the VF? Are static …
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Visual correlates of functional difficulties in Parkinson's disease and Alzheimer's disease
… to abnormal performance. In AD and PD, reduced contrast sensitivity and other visual difficulties have the potential to impact everyday functioning. The relation of PD visuospatial problems, and AD and PD contrast sensitivity deficits to higher-order impairments is understudied. The present …
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Display Technology and Ambient Illumination Influences on Visual Fatigue at VDT Workstations
… battery, subjective image quality judgments, and contrast sensitivity shifts. Two cathode ray tube (CRT) and two active-matrix LCD (AMLCD) monitors were used in this study. While many instances of the monitors as a whole caused significant differences in reports of visual fatigue, performance, …
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Development of video quality metrics based on psychovisual models of early vision
… parameters of a multidimensional model of human contrast sensitivity appropriate to modern display technology of viewing conditions. The contrast sensitivity function works like a filter through which visual stimuli must pass to be perceived by the observer. Only video artefacts in the passband …
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Predicting Vision Loss In Healthy Aging With Manganese-Enhanced Mri Of The Rat Eye
… and discovered an age-related change in sensitivity to L-VGCC blocker diltiazem. Based on Western blot studies, we find this sensitivity change to be consistent with the age-dependant appearance of drug-insensitive L-VGCC isoforms. Longitudinally, rats starting the study with relatively …
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The Relationship Between Vision and Athletic Performance
… on the following visual measures: visual acuity, contrast sensitivity, depth perception, choice reaction time, hand and eye dominance, and peripheral attention. A copy of each team's cumulative seasonal statistics was obtained and used as a measure of athletic ability. These statistics contained …
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Spatial and temporal aspects of visual performance in relation to light level and normal aging
… and/or time in mesopic conditions, including contrast sensitivity, temporal flicker sensitivity and visual acuity. The first two studies determined the effect of the aging of the retina on spatial and temporal contrast sensitivity at photopic and mesopic light levels. The literature states …
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An image quality analysis of ANVIS-6 night vision goggles
… Transfer Function Area (MTFA), Integrated Contrast Sensitivity (leS), Square Root Integral (SQRI), Resolution, and Signal-to-Noise Ratio (SNR). The performance tasks were detection and recognition of targets under various levels of moon illumination. The metric that best related to target …
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The effect of aberrations and light scatter on visual performance at photopic and mesopic light levels
The Contrast Acuity Assessment (CAA) test was developed to assess the minimum spatial vision requirements for commercial pilots. The goal of the CAA test was for it to be sensitive to retinal image degradation in subjects who had undergone excimer laser refractive surgery. Increased aberrations and …
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