Show simple item record

dc.contributor.authorMcIlhagga, William H.
dc.date.accessioned2021-03-03T17:10:18Z
dc.date.accessioned2021-03-09T08:41:41Z
dc.date.available2021-03-03T17:10:18Z
dc.date.available2021-03-09T08:41:41Z
dc.date.issued2021-05
dc.identifier.citationMcIlhagga WH (2021) Classification images for contrast discrimination. Vision Research. 182: 36-45.en_US
dc.identifier.urihttp://hdl.handle.net/10454/18390
dc.descriptionYesen_US
dc.description.abstractContrast discrimination measures the smallest difference in contrast (the threshold) needed to successfully tell two stimuli apart. The contrast discrimination threshold typically increases with contrast. However, for low spatial frequency gratings the contrast threshold first increases, but then starts to decrease at contrasts above about 50%. This behaviour was originally observed in contrast discrimination experiments using dark spots as stimuli, suggesting that the contrast discrimination threshold for low spatial frequency gratings may be dominated by responses to the dark parts of the sinusoid. This study measures classification images for contrast discrimination experiments using a 1 cycle per degree sinusoidal grating at contrasts of 0, 25%, 50% and 75%. The classification images obtained clearly show that observers emphasize the darker parts of the sinusoidal grating (i.e. the troughs), and this emphasis increases with contrast. At 75% contrast, observers almost completely ignored the bright parts (peaks) of the sinusoid, and for some observers the emphasis on the troughs is already evident at contrasts as low as 25%. Analysis using a Hammerstein model suggests that the bias towards the dark parts of the stimulus is due to an early nonlinearity, perhaps similar to that proposed by Whittle.en_US
dc.language.isoenen_US
dc.relation.isreferencedbyhttps://doi.org/10.1016/j.visres.2021.01.002en_US
dc.rights© 2021 Elsevier. Reproduced in accordance with the publisher's self-archiving policy. This manuscript version is made available under the CC-BY-NC-ND 4.0 license (https://creativecommons.org/licenses/by-nc-nd/4.0/)en_US
dc.subjectContrast discriminationen_US
dc.subjectClassification imagesen_US
dc.subjectModellingen_US
dc.titleClassification images for contrast discriminationen_US
dc.status.refereedYesen_US
dc.date.Accepted2021-01-07
dc.date.application2021-02-13
dc.typeArticleen_US
dc.date.EndofEmbargo2022-02-13
dc.type.versionAccepted manuscripten_US
dc.description.publicnotesThe full-text of this article will be released for public view at the end of the publisher embargo on 13 Feb 2022.en_US
dc.date.updated2021-03-03T17:10:29Z
refterms.dateFOA2021-03-09T08:48:41Z
dc.openaccess.statusGreenen_US


Item file(s)

Thumbnail
Name:
ClassificationImagesForContras ...
Embargo:
2022-02-13
Size:
664.0Kb
Format:
PDF
Description:
mcilhagga_2021

This item appears in the following Collection(s)

Show simple item record