Electrophysiological evidence for the existence of orientation and size detectors in the human visual system
F. W. Campbell,L. Maffei +1 more
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TLDR
The evoked potential in response to a grating alternating in phase at 8 c/s was recorded as a function of contrast from the occiput of man.Abstract:
1 The evoked potential in response to a grating alternating in phase at 8 c/s was recorded as a function of contrast from the occiput of man
2 It was found that a linear relation exists between the log of contrast and the amplitude of the evoked potential
3 Extrapolation to zero amplitude voltage of the regression line between the amplitude of the evoked potential and log contrast predicts the psychophysical threshold This law was found to hold over the wide range of spatial frequencies tested
4 Below 3 c/deg the results are best fitted with two regression lines; one of these is generated from the foveal and the other from the parafoveal representation in the cortex
5 The slope of the regression lines was found to be almost independent of either the spatial frequency or the area of the stimulus grating
6 The slope of the regression lines could be markedly increased by using as a stimulus either two different spatial frequencies, or two different orientations, presented simultaneously
7 Using the evoked potential the selectivity to orientation was found to be so high that a channel was not influenced by another orientation 15° away
8 The channels selectively sensitive to spatial frequency were highly selective and were not influenced by another spatial frequency one octave removed in spatial frequency
9 It is concluded that in man there exist neurones highly selective to both orientation and spatial frequencyread more
Citations
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Visibility of structured and unstructured images.
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Neuromagnetic studies of human vision: noninvasive characterization of functional neural architecture
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Detection and Measurement of Visual Impairment in Pre-Verbal Children
TL;DR: The recording and processing of visual evoked potentials and electroretinogram include artefact rejection algorithms and a statistical analysis for the evaluation of visual functions in non verbal children.
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Luminance discrimination, color contrast, and multiple mechanisms.
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TL;DR: Results indicate that the effects of chromatic contrast may be mediated by local contrast mechanisms, but that the relationship between threshold and luminance contrast is not mediated entirely by these local Contrast mechanisms.
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Adult levels of meridional anisotropy and contrast threshold in 5-year olds.
TL;DR: It is shown that 5-yr-old children have greater sensitivity for vertical and horizontal sinusoidal gratings than for obliques, suggesting that meridional anisotropy does not develop over an extended period of childhood as was previously reported.
References
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Journal ArticleDOI
Receptive fields, binocular interaction and functional architecture in the cat's visual cortex
David H. Hubel,Torsten N. Wiesel +1 more
TL;DR: This method is used to examine receptive fields of a more complex type and to make additional observations on binocular interaction and this approach is necessary in order to understand the behaviour of individual cells, but it fails to deal with the problem of the relationship of one cell to its neighbours.
Journal ArticleDOI
Receptive fields and functional architecture of monkey striate cortex
David H. Hubel,Torsten N. Wiesel +1 more
TL;DR: The striate cortex was studied in lightly anaesthetized macaque and spider monkeys by recording extracellularly from single units and stimulating the retinas with spots or patterns of light, with response properties very similar to those previously described in the cat.
Journal ArticleDOI
Receptive fields of single neurones in the cat's striate cortex
David H. Hubel,Torsten N. Wiesel +1 more
TL;DR: The present investigation, made in acute preparations, includes a study of receptive fields of cells in the cat's striate cortex, which resembled retinal ganglion-cell receptive fields, but the shape and arrangement of excitatory and inhibitory areas differed strikingly from the concentric pattern found in retinalganglion cells.
Journal ArticleDOI
Application of fourier analysis to the visibility of gratings
F. W. Campbell,John G. Robson +1 more
TL;DR: The contrast thresholds of a variety of grating patterns have been measured over a wide range of spatial frequencies and the results show clear patterns of uniformity in the response to grating noise.
Journal ArticleDOI
Receptive fields and functional architecture in two nonstriate visual areas (18 and 19) of the cat.
David H. Hubel,Torsten N. Wiesel +1 more
TL;DR: To UNDERSTAND VISION in physiological terms represents a formidable problem for the biologist, and one approach is to stimulate the retina with patterns of light while recording from single cells or fibers at various points along the visual pathway.
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