Linked Life Data

1891807

Source:http://linkedlifedata.com/resource/pubmed/id/1891807

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
7-8
pubmed:dateCreated
1991-10-15
pubmed:abstractText
The frequency transfer properties of horizontal cells in the cat retina were studied as a function of the mean light intensity level and stimulus contrast. To this end, horizontal cell responses to sinusoidally modulated light stimuli were recorded intracellularly in the optically intact, in vivo eye. The light stimulus consisted of a 3.9 deg dia. spot superimposed on a steady background (8.8 deg dia.). A discrete Fourier analysis was performed in order to describe the amplitude and phase characteristics of the linear response component and in order to specify the nonlinear distortion of the response. The amplitude of the fundamental Fourier component was found to increase linearly with the contrast of the sinusoidal light intensity modulation. Increasing the mean light level while keeping the contrast constant caused a frequency dependent increase in response amplitude. The increase was most pronounced at high temporal frequencies and resulted in a conspicuous increase of the flicker fusion frequency. Steady background illumination caused a reduction of the response amplitudes at the lower temporal frequencies. Responses in the high frequency range, however, were not affected. The phase shifts of the fundamental Fourier components were found to diminish at increasing mean illumination levels. The harmonic distortion of horizontal cell responses to sinewave flicker was studied as a function of stimulus frequency and stimulus contrast. By comparing the data obtained using sinusoidal light intensity modulation with the intensity profiles described in a preceding paper it was investigated to what extent the harmonic distortion can be explained by the nonlinearity expressed in the response vs intensity profiles.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:status
MEDLINE
pubmed:issn
0042-6989
pubmed:author
pubmed:issnType
Print
pubmed:volume
31
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1129-42
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1991
pubmed:articleTitle
Light adaptation and frequency transfer properties of cat horizontal cells.
pubmed:affiliation
Department of Comparative Physiology, Utrecht University, The Netherlands.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't