Linked Life Data

2629214

Source:http://linkedlifedata.com/resource/pubmed/id/2629214

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
8
pubmed:dateCreated
1990-4-26
pubmed:abstractText
We have measured threshold disparity as a function of the spatial frequency (0.25-20 c/deg) and contrast (0.02-0.75) of sine-wave gratings. In forced-choice trials, subjects indicated whether a target grating had crossed or uncrossed disparity relative to a reference grating. Thresholds were lowest near 3 c/deg and rose in proportion to spatial period at lower frequencies. Above 3 c/deg, there were marked individual differences. Across the range of spatial frequencies, disparity sensitivity and contrast sensitivity were correlated (r = 0.84). Threshold disparity was inversely proportional to the square root of contrast. When the contrast seen by one eye was reduced producing unequal monocular contrasts, threshold disparity rose more than when the contrast seen by the two eyes was reduced by the same amount. Our results have implications for stereo models that use zero crossings, peaks and troughs, or centroids as matching primitives. These models can account for the decline in disparity sensitivity at low sapatial frequencies but only the peak model satisfactorily accounts for the effect of contrast. If the limiting sources of noise in the two eyes are highly correlated, the effect of unequal monocular contrast can be accounted for using a differential-amplifier principle.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:status
MEDLINE
pubmed:issn
0042-6989
pubmed:author
pubmed:issnType
Print
pubmed:volume
29
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
989-1004
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1989
pubmed:articleTitle
Stereopsis and contrast.
pubmed:affiliation
Department of Psychology, University of Minnesota, Minneapolis 55455.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.