Results 201 to 210 of about 520,684 (243)

Vision in dementia: Contrast effects

Neurological Research, 1996
Contrast sensitivity has been shown to be affected in Alzheimer's disease (Ad). We investigated low contrast acuity and contrast sensitivity using clinical test charts in this patient population. Additionally, we tested patients with vascular dementia (vd) and mixed dementia (md), (Alzheimer' with vascular dementia).
Mary Louise Kean, Vasudevan Lakshminarayanan, Malcolm B. Dick, John Lagrave, Rodman Shankle   +4 more
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Characteristic of Contrast Vision

1987
Six typical threshold contrast-sensitivity functions, frequently found in our ophthalmological practice, are analyzed, using the concept of spatial filtering in order to understand how we see the everyday world in the case of normal and abnormal vision.
Maria L. F. De Mattiello, Ernesto Mazzeo, A. Gonella   +2 more
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Contrasting the Vision and the Reality

Journal of Religion & Abuse, 2001
Abstract This article advocates the use of developing individual core ethical values as the first step in a process of using one's own principles as a means of keeping focused and grounded. The article does not stop but encourages the reader to actually use the value through the introduction of a straightforward yet sophisticated decision model ...
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Contrast Sensitivity and Functional Vision

International Ophthalmology Clinics, 2003
How well does a person see faces in a crowd, read a newspaper, or drive an automobile at night? These are vital questions about a person's quality of life and safety. Obtaining answers to these questions requires tests of functional vision.
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Vision channels, contrast sensitivity, and functional vision

SPIE Proceedings, 2004
The neurophysiology and psychophysics of vision provide the basis for vision channels. Vision channels are the foundation of understanding spatial vision. This understanding has led to the development of a general model of visual perception and tests of functional vision.
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Spatial Vision and Aging. I: Contrast Sensitivity

Journal of Gerontology, 1980
Contrast sensitivity functions (CSFs) were measured for two groups of healthy observers, a younger group with mean age 18.5 years and an older group with mean age 73 years. Although the two groups had virtually identical sensitivities to high spatial frequencies (gratings with narrow bars), the younger observers were three times more sensitive at low ...
Robert Sekuler, Lucinda Picciano Hutman
openaire   +3 more sources

Models of contrast sensitivity in human vision

IEEE Transactions on Systems, Man, and Cybernetics, 1993
Eight models are examined as input-output representations of steady-state vision in humans at moderate to low level illumination. Three new models for visual contrast sensitivity are introduced and evaluated using contrast sensitivity function (CSF) data with samples on both narrow and wide frequency ranges.
G.C. Gilmore, F.L. Royer, C.W. Thomas
openaire   +2 more sources

The embodied mind: Contrasting visions

Mind, Culture, and Activity, 1999
This article presents a critical examination and discussion of 2 arguments in support of the embodied mind position as developed within the philosophical literature of the Cognitive Linguistics paradigm. Employing the dialectical Materialist approach of Evald Ilyenkov (1997), closely allied to the cultural‐historical and activity theory traditions, the
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Temporal properties of spatial contrast vision

Vision Research, 1987
The temporal characteristics of spatial contrast vision at and above threshold were assessed psychophysically using sinusoidal gratings and a contrast-matching method. Temporal frequency response curves became flatter as contrast level increased. An impulse response model was fitted to these flicker data, and used to make predictions about temporal ...
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A silicon retina for polarization contrast vision

IJCNN'99. International Joint Conference on Neural Networks. Proceedings (Cat. No.99CH36339), 2003
Polarization vision is prevalent among insects, and offers visual capabilities that contribute to object discrimination and homing tasks. We present a CMOS imager that is capable of extracting polarization contrast in a scene. A similar visual modality has been seen in Octopus.
Z.K. Kalayjian, Andreas G. Andreou
openaire   +2 more sources