Baker, Daniel H orcid.org/0000-0002-0161-443X and Meese, Tim S (2007) Binocular contrast interactions:dichoptic masking is not a single process. Vision Research. pp. 3096-107. ISSN 0042-6989
Abstract
To decouple interocular suppression and binocular summation we varied the relative phase of mask and target in a 2IFC contrast-masking paradigm. In Experiment I, dichoptic mask gratings had the same orientation and spatial frequency as the target. For in-phase masking, suppression was strong (a log-log slope of approximately 1) and there was weak facilitation at low mask contrasts. Anti-phase masking was weaker (a log-log slope of approximately 0.7) and there was no facilitation. A two-stage model of contrast gain control [Meese, T.S., Georgeson, M.A. and Baker, D.H. (2006). Binocular contrast vision at and above threshold. Journal of Vision, 6: 1224-1243] provided a good fit to the in-phase results and fixed its free parameters. It made successful predictions (with no free parameters) for the anti-phase results when (A) interocular suppression was phase-indifferent but (B) binocular summation was phase sensitive. Experiments II and III showed that interocular suppression comprised two components: (i) a tuned effect with an orientation bandwidth of approximately +/-33 degrees and a spatial frequency bandwidth of >3 octaves, and (ii) an untuned effect that elevated threshold by a factor of between 2 and 4. Operationally, binocular summation was more tightly tuned, having an orientation bandwidth of approximately +/-8 degrees , and a spatial frequency bandwidth of approximately 0.5 octaves. Our results replicate the unusual shapes of the in-phase dichoptic tuning functions reported by Legge [Legge, G.E. (1979). Spatial frequency masking in human vision: Binocular interactions. Journal of the Optical Society of America, 69: 838-847]. These can now be seen as the envelope of the direct effects from interocular suppression and the indirect effect from binocular summation, which contaminates the signal channel with a mask that has been suppressed by the target.
Metadata
Item Type: | Article |
---|---|
Authors/Creators: |
|
Copyright, Publisher and Additional Information: | © 2007, Elsevier. This is an author-produced version of the published paper. Uploaded in accordance with the publisher’s self-archiving policy. |
Dates: |
|
Institution: | The University of York |
Academic Units: | The University of York > Faculty of Sciences (York) > Psychology (York) |
Depositing User: | Pure (York) |
Date Deposited: | 16 Dec 2016 16:36 |
Last Modified: | 16 Oct 2024 12:18 |
Published Version: | https://doi.org/10.1016/j.visres.2007.08.013 |
Status: | Published |
Refereed: | Yes |
Identification Number: | 10.1016/j.visres.2007.08.013 |
Open Archives Initiative ID (OAI ID): | oai:eprints.whiterose.ac.uk:109662 |