Document Detail


Visual discrimination of orientation statistics in crowded and uncrowded arrays.
MedLine Citation:
PMID:  21163954     Owner:  NLM     Status:  MEDLINE    
Abstract/OtherAbstract:
When required to identify the orientation of an item outside the center of the visual field, the mean orientation predicts performance better than the orientation of any individual item in that region. Here I examine whether the visual system also preserves the variance of orientations in these so-called "crowded" displays. In Experiment 1, I determined the separation between items necessary to prevent neighbors from interfering with discrimination between different orientations in a single, target item. In Experiment 2, I used this separation and measured the effect of orientation variance on discrimination between mean orientations in these consequently uncrowded displays. In Experiment 3, I measured the relationship between the just-noticeable difference in variance and the smaller of two orientation variances in uncrowded displays. Finally, in Experiments 4 and 5, I reduced the separation between items and measured the effect of crowding on mean and variance discriminations. When considered together, the results of all these experiments imply that the visual system computes orientation variances with both more efficiency and greater precision than it computes orientation means. Although crowding made it difficult for some observers to discriminate between small amounts of orientation variance, it had no other significant effect on visual estimates mean orientation and orientation variance.
Authors:
Joshua A Solomon
Related Documents :
8148334 - Electroretinogram b/a wave ratio improvement in central retinal vein obstruction.
474084 - Stimulus alternation and fast retinal potentials: photopic anc scotopic contributions.
17614114 - Eccentricity-dependent changes in local onset and offset responses in patients with pro...
15703474 - Comparison of the retinal structure and function in four bird species as a function of ...
17708894 - Light signal transduction in plants.
15677064 - Evaluation of perceived and self-reported manual forces exerted in occupational materia...
Publication Detail:
Type:  Journal Article; Research Support, Non-U.S. Gov't     Date:  2010-12-16
Journal Detail:
Title:  Journal of vision     Volume:  10     ISSN:  1534-7362     ISO Abbreviation:  J Vis     Publication Date:  2010  
Date Detail:
Created Date:  2010-12-17     Completed Date:  2011-04-07     Revised Date:  2011-08-23    
Medline Journal Info:
Nlm Unique ID:  101147197     Medline TA:  J Vis     Country:  United States    
Other Details:
Languages:  eng     Pagination:  19     Citation Subset:  IM    
Affiliation:
City University London, London, UK. J.A.Solomon@city.ac.uk
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Descriptor/Qualifier:
Cues
Differential Threshold
Form Perception / physiology*
Humans
Orientation / physiology*
Photic Stimulation / methods*
Psychophysics / methods
Space Perception / physiology*
Visual Acuity / physiology*
Visual Fields / physiology
Comments/Corrections
Erratum In:
J Vis. 2011;11(8). doi:10.1167/11.8.3

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine


Previous Document:  Global motion processing in human color vision: a deficit for second-order stimuli.
Next Document:  Phase changes induced by optical aberrations degrade letter and face acuity.