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The Influence of Contrasts on Directional and Spatial Frequency Tuning in Visual Cortex Areas 17/18 of the Cat

PURPOSE: The purpose of this study was to investigate the effects of contrast display exposure on neuronal directional and spatial frequency tuning. Neuronal responses were recorded from ninety-four neurons in cortical areas 17 and 18 in two adult cats. METHODS: A multi-channel microelectrode was im...

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Autor principal: Kim, Jong-Nam
Formato: Texto
Lenguaje:English
Publicado: The Korean Ophthalmological Society 2011
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3039195/
https://www.ncbi.nlm.nih.gov/pubmed/21350695
http://dx.doi.org/10.3341/kjo.2011.25.1.48
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author Kim, Jong-Nam
author_facet Kim, Jong-Nam
author_sort Kim, Jong-Nam
collection PubMed
description PURPOSE: The purpose of this study was to investigate the effects of contrast display exposure on neuronal directional and spatial frequency tuning. Neuronal responses were recorded from ninety-four neurons in cortical areas 17 and 18 in two adult cats. METHODS: A multi-channel microelectrode was implanted in cortical areas 17 and 18 of two paralyzed and anaesthetized cats. Various drifting sinusoidal grating contrast displays were presented to one of the cats' eyes in the visual field. Contour plots based on the neuronal responses to the drifting sinusoidal grating displays using various contrasts (i.e., 0.4, 0.7, and 1.0) and velocities (i.e., 4.6, 13.9, 23.1, 32.3, 41.5, 50.8, and 60.0 deg/sec) were plotted as a function of the spatial frequency and the direction associated with each velocity and contrast used. RESULTS: Five parameters were extracted from these contour plots: 1) optimum response, 2) preferred direction, 3) optimum spatial frequency, 4) directional tuning width, and 5) spatial frequency bandwidth. To determine the optimal velocity, each parameter was plotted against each of the specific display contrasts used, and a 'best fit' line was established. Response amplitudes were dependent on the type of contrast utilized; however, the spatial frequency and directional tuning properties were stable for the cortical neurons assessed. CONCLUSIONS: The results of the presentation of different contrasts on neuronal directional and spatial frequency tuning are consistent with behavioral results when medium and high contrast displays are used.
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spelling pubmed-30391952011-02-24 The Influence of Contrasts on Directional and Spatial Frequency Tuning in Visual Cortex Areas 17/18 of the Cat Kim, Jong-Nam Korean J Ophthalmol Original Article PURPOSE: The purpose of this study was to investigate the effects of contrast display exposure on neuronal directional and spatial frequency tuning. Neuronal responses were recorded from ninety-four neurons in cortical areas 17 and 18 in two adult cats. METHODS: A multi-channel microelectrode was implanted in cortical areas 17 and 18 of two paralyzed and anaesthetized cats. Various drifting sinusoidal grating contrast displays were presented to one of the cats' eyes in the visual field. Contour plots based on the neuronal responses to the drifting sinusoidal grating displays using various contrasts (i.e., 0.4, 0.7, and 1.0) and velocities (i.e., 4.6, 13.9, 23.1, 32.3, 41.5, 50.8, and 60.0 deg/sec) were plotted as a function of the spatial frequency and the direction associated with each velocity and contrast used. RESULTS: Five parameters were extracted from these contour plots: 1) optimum response, 2) preferred direction, 3) optimum spatial frequency, 4) directional tuning width, and 5) spatial frequency bandwidth. To determine the optimal velocity, each parameter was plotted against each of the specific display contrasts used, and a 'best fit' line was established. Response amplitudes were dependent on the type of contrast utilized; however, the spatial frequency and directional tuning properties were stable for the cortical neurons assessed. CONCLUSIONS: The results of the presentation of different contrasts on neuronal directional and spatial frequency tuning are consistent with behavioral results when medium and high contrast displays are used. The Korean Ophthalmological Society 2011-02 2011-01-17 /pmc/articles/PMC3039195/ /pubmed/21350695 http://dx.doi.org/10.3341/kjo.2011.25.1.48 Text en © 2011 The Korean Ophthalmological Society http://creativecommons.org/licenses/by-nc/3.0/ This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/3.0/) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.
spellingShingle Original Article
Kim, Jong-Nam
The Influence of Contrasts on Directional and Spatial Frequency Tuning in Visual Cortex Areas 17/18 of the Cat
title The Influence of Contrasts on Directional and Spatial Frequency Tuning in Visual Cortex Areas 17/18 of the Cat
title_full The Influence of Contrasts on Directional and Spatial Frequency Tuning in Visual Cortex Areas 17/18 of the Cat
title_fullStr The Influence of Contrasts on Directional and Spatial Frequency Tuning in Visual Cortex Areas 17/18 of the Cat
title_full_unstemmed The Influence of Contrasts on Directional and Spatial Frequency Tuning in Visual Cortex Areas 17/18 of the Cat
title_short The Influence of Contrasts on Directional and Spatial Frequency Tuning in Visual Cortex Areas 17/18 of the Cat
title_sort influence of contrasts on directional and spatial frequency tuning in visual cortex areas 17/18 of the cat
topic Original Article
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3039195/
https://www.ncbi.nlm.nih.gov/pubmed/21350695
http://dx.doi.org/10.3341/kjo.2011.25.1.48
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