Linked Life Data

12350426

Source:http://linkedlifedata.com/resource/pubmed/id/12350426

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
20
pubmed:dateCreated
2002-9-27
pubmed:abstractText
Thresholds for discriminating the orientation of unreferenced horizontal and vertical lines were measured in subjects with congenital nystagmus (CN) and normal observers and compared to the variability of torsional eye position. Orientation thresholds were determined for horizontal and vertical lines between 0.7 degrees and 5.6 degrees in length, that were presented binocularly for 20-1280 ms. The variability of torsional eye position was assessed using the magnetic search coil technique. Orientation thresholds improved with line length and stimulus duration in both groups of observers. Some of the subjects with CN exhibited poorer than normal thresholds, particularly when the length of the line was short. In addition, orientation discrimination in the subjects with CN was consistently anisotropic, with significantly lower thresholds for horizontal than vertical lines. The standard deviations of torsional eye position were larger in the subjects with CN than in normal observers. However, orientation thresholds were poorer than expected from the variability of torsional eye position in normal observers, and better than expected on the basis of torsional variability in some of the subjects with CN. These results imply that torsional variability does not limit normal orientation thresholds and that torsional eye movements in CN are compensated partially by extraretinal signals.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
0042-6989
pubmed:author
pubmed:issnType
Print
pubmed:volume
42
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
2395-407
pubmed:dateRevised
2007-11-15
pubmed:meshHeading
pubmed:year
2002
pubmed:articleTitle
Orientation discrimination and variability of torsional eye position in congenital nystagmus.
pubmed:affiliation
College of Optometry, University of Houston, 505 J. Davis Armistead Building, Houston, TX 77204-2020, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.