Results 221 to 230 of about 573,259 (262)

Functional visual streams

Current Biology, 1992
The idea that visual signals relayed by the parvocellular and magnocellular subdivisions of the lateral geniculate nucleus remain segregated in the cerebral cortex has attracted considerable attention. It has been proposed that parvocellular contributions dominate in the temporal visual cortex, and that magnocellular contributions dominate in the ...
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The Visual Function of the Vitamins A

1961
Publisher Summary The retinas of most vertebrate eyes possess two kinds of light receptor: rods, for vision in dim light, and cones, for vision in bright light and for color vision. Each of these organs contains a photosensitive pigment, which bleaches on exposure to light. Some aspect of this process leads to a nervous excitation, which, transmitted
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Visualizing transcendental functions

Computing in Science & Engineering, 2000
Scientists and engineers often need to compute mathematical functions that depend in a complicated way on their parameters. Such functions-especially those whose analytical properties researchers have studied extensively-are called transcendental functions or special functions. There are three important reasons for visualizing such functions: to better
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VISUAL FUNCTION IN DYSLEXIA

American journal of optometry and archives of American Academy of Optometry, 1968
Abstract The problem of the seriously retarded reader is examined to determine the role of vision. The most obvious visual factors, such as acuity and refractive error, do not seem related to the problem.
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The Importance of the Phase Transfer Function to Visual Function and Visual Quality Metrics

Journal of Refractive Surgery, 2004
<p>ABSTRACT</p><p>PURPOSE: To propose a vision quality metric that directly incorporates the phase transfer function.</p><p>METHODS: The process of retinal image formation from the pupil to the retina is presented to identify possible domains for calculating vision quality metrics.
Edwin J, Sarver, Raymond A, Applegate
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The Loss of Visual Function in Glaucoma

Seminars in Ophthalmology, 2000
This article reviews innovative techniques for assessing the visual field and for examining glaucoma patients for evidence of visual field progression. The authors discuss the algorithms for assessing change in visual fields used in each of several multicenter studies sponsored by the National Eye Institute.
P A, Sample, C F, Bosworth, R N, Weinreb
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Functional Visual Loss in Children

Ophthalmology, 1986
Twenty-three children (16 girls, 7 boys, aged 6-17 years) who presented with the specific complaint of blurred vision were diagnosed as having functional visual loss. Symptoms were intermittent in seven children. Associated signs and symptoms were common and included headaches, visual field loss, diplopia, micropsia, voluntary nystagmus, and spasm of ...
R A, Catalono, J W, Simon, G B, Krohel, P N, Rosenberg   +3 more
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Visual Function and Academic Performance

American Journal of Ophthalmology, 1985
Evaluation of 1,910 first-, second-, and third-grade students indicated that visual function and academic performance as measured by reading were not positively related. Visual function tests included visual acuity, muscle balance, preferred eye and hand, color vision, refraction, sensory and motor function, and a writing and drawing task.
E M, Helveston, J C, Weber, K, Miller, K, Robertson, G, Hohberger, R, Estes, F D, Ellis, N, Pick, B H, Helveston   +8 more
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Modification of visual function by early visual experience

Bulletin der Schweizerischen Akademie der Medizinischen Wissenschaften, 1976
Physiological experiments, involving recording from the visual cortex in young kittens and monkeys, have given new insight into human developmental disorders. In the visual cortex of normal cats and monkeys most neurones are selectively sensitive to the orientation of moving edges and they receive very similar signals from both eyes. Even in very young
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Subcortical visual function in the newborn

Pediatric Neurology, 1990
Early behavioral visual function in infants may not depend upon the geniculocalcarine pathway but may be mediated through more primitive subcortical pathways. This subcortical visual system may exist in early life and be responsible for visual pursuit and perhaps fixation.
R D, Snyder, S K, Hata, B S, Brann, R M, Mills   +3 more
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