Results 241 to 250 of about 2,196,079 (289)

Electrophysiological correlates of visual masking

International Journal of Neuroscience, 1985
The phenomenon of paracontrast documented by means of psychophysical techniques has not been readily demonstrable using electrophysiological responses as an index of masking. We have analyzed averaged cortical potentials during presentation of visual stimuli that produce psychophysical masking.
M, Kaitz, J, Monitz, R, Nesher
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Electrophysiological assessment of visual deficit in glaucoma

Applied Optics, 1986
Glaucoma is a progressive and irreversible damage to the optic nerve with a typical optic disc appearance (pallor, enlargement and cupping) and a specific pattern of sensitivity loss apparent on visual field testing. It develops in eyes with abnormal intraocular pressure dynamics. Although glaucoma is not curable, drug or surgical treatment can relieve
V G, Sutija, S B, Eiden, D, Wicker, D, Horn, J, Cooper, W, Appleman   +5 more
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Electrophysiology of the human visual system

Ophthalmic and Physiological Optics, 1983
Abstract Progress during the last 60 years has revealed numerous electrical signals arising from many parts of the visual system. These now play an essential part in the detection of many pathological conditions.
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ELECTROPHYSIOLOGY OF VISUAL AND PERCEPTUAL ACTIVITY

Journal of Psychiatric Research, 1971
THE STUDY of vision is an ongoing process in which knowledge accumulated through experimentation serves both as a basis and as a stimulus for further investigations. The purposes of this article are to review some of the visual research conducted in the Division of Neuropsychiatry at the Walter Reed Army Institute of Research under the leadership of Dr.
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Electrophysiological Assessment of Visual Pathways in Glaucoma

European Journal of Ophthalmology, 1997
Purpose. To assess nerve conduction in visual pathways in patients with open-angle glaucoma. Methods. Pattern-electroretinograms (PERG) and visual-evoked potentials (VEP) were simultaneously recorded in 16 patients with open-angle ...
V, Parisi, C, Pernini, C, Guinetti, R, Neuschuler, M G, Bucci   +4 more
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Electrophysiological retinal changes and visual deprivation

Vision Research, 1968
Abstract Adult cats were subjected to monocular or binocular light deprivation for periods ranging from 36 hr to 3 weeks. One week of deprivation resulted in a significant reduction of the ERG and an increased susceptibility to light adaptation, produced by dim background illumination or by continuous flicker. Following one week of light deprivation,
A C, Cornwell, S K, Sharpless
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Electrophysiology of the postreceptoral visual pathway in mice

Documenta Ophthalmologica, 2002
Pattern VEPs have been recorded locally from the binocular portion of the primary visual cortex of wild type- and different transgenic mice by means of microelectrodes. Local pattern VEPs have been used on the one hand to obtain information on basic cortical layout (topography, laminar analysis) and ocularity (relative contribution of the contralateral
V. PORCIATTI, PIZZORUSSO, TOMMASO, L. MAFFEI   +2 more
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Electrophysiology of Visual Attention

1990
The ability of human observers to deploy their attention rapidly to selected portions of a visual scene has important consequences for perception. A rapidly expanding research literature has established that stimuli positioned at or near an attended location in the visual field are processed more efficiently than are stimuli at some distance from the ...
Steven A. Hillyard, George R. Mangun, Steven J. Luck, Hans-Jochen Heinze   +3 more
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The earliest electrophysiological correlate of visual awareness?

Brain and Cognition, 2008
To examine the neural correlates and timing of human visual awareness, we recorded event-related potentials (ERPs) in two experiments while the observers were detecting a grey dot that was presented near subjective threshold. ERPs were averaged for conscious detections of the stimulus (hits) and nondetections (misses) separately.
Koivisto, Mika, Lähteenmäki, Mikko, Sørensen, Thomas Alrik, Vangkilde, Signe, Overgaard, Morten, Revonsuo, Antti   +5 more
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The importance of electrode position in visual electrophysiology

Documenta Ophthalmologica, 2017
The DTL fibre electrode is commonly used to record the electric potentials elicited by stimulation of the retina. Two positions are commonly used: it is placed either on the cornea along the lower lid or in the conjunctival fornix. The PERG and OPs have previously been examined and compared under both conditions.
A. Kurtenbach, S. Kramer, T. Strasser, E. Zrenner, H. Langrová   +4 more
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