Dual nonlinearities regulate contrast sensitivity in pattern discrimination tasks

Vision Research
L A Olzak, J P Thomas

Abstract

Many current psychophysical models propose that visual processing in cortex is hierarchical, with nonlinearities sandwiched between linear stages of processing. In earlier publications, we proposed a model of this type to account for masking effects found with spatial frequency and orientation discriminations. Our model includes two nonlinear mechanisms that regulate contrast sensitivity in early cortical mechanisms. The first is a local within-pathway nonlinearity that accelerates at low contrasts but is compressive at high. The second is a pooled nonlinear gain control process that operates over a broad range of neurons with different tuning characteristics. Here, we test predictions of the model for spatial frequency discriminations. The model predicts that at low contrasts, adding a grating mask oriented parallel to test gratings will improve discrimination performance via operation of the within-pathway nonlinearity, analogous to the "dipper effect" found with contrast discriminations. Adding an orthogonally oriented mask is predicted to have no effect at low contrasts, where pooled gain control processes contribute little to performance. At high contrasts, the model predicts that performance will asymptote and become inde...Continue Reading

References

Jun 1, 1979·Journal of the Optical Society of America·G E Legge
Dec 1, 1978·The Journal of Physiology·R M Shapley, J D Victor
Oct 1, 1992·Vision Research·L A Olzak, J P Thomas
Aug 1, 1992·Vision Research·W S Geisler, D G Albrecht
May 1, 1992·Visual Neuroscience·E A BenardeteB W Knight
Jan 1, 1991·Vision Research·M S Landy, J R Bergen
Jan 1, 1991·Vision Research·L A Olzak, J P Thomas
May 1, 1990·Journal of the Optical Society of America. A, Optics and Image Science·J Malik, P Perona
Dec 1, 1989·Proceedings of the National Academy of Sciences of the United States of America·C ChubbJ A Solomon
Jan 1, 1985·Vision Research·A M SillitoJ A Kemp
Nov 1, 1988·The Journal of Physiology·P BobakM S Marx
Jan 1, 1987·Experimental Brain Research·M C MorroneH D Speed
Sep 24, 1986·Brain Research·E J DeBruyn, A B Bonds
Oct 1, 1974·Vision Research·J Nachmias, R V Sansbury
Dec 1, 1974·Vision Research·C F Stromeyer, S Klein
Sep 1, 1971·Journal of the Optical Society of America·M B SachsJ G Robson
Nov 1, 1966·The Journal of Physiology·F W Campbell, J J Kulikowski
Oct 22, 1982·Proceedings of the Royal Society of London. Series B, Containing Papers of a Biological Character·M C MorroneL Maffei
Feb 1, 1984·The Journal of Physiology·D G AlbrechtD B Hamilton
Jun 1, 1983·Journal of the Optical Society of America·J P Thomas
Jan 1, 1981·Vision Research·J M Foley, G E Legge
Dec 1, 1980·Journal of the Optical Society of America·G E Legge, J M Foley
Sep 1, 1994·Journal of the Optical Society of America. A, Optics, Image Science, and Vision·C ChubbM S Landy
Dec 1, 1994·Vision Research·B B LeeJ Kremers
Jun 1, 1994·Journal of the Optical Society of America. A, Optics, Image Science, and Vision·J M Foley
Mar 1, 1996·Vision Research·B B Lee
Apr 1, 1996·Journal of the Optical Society of America. A, Optics, Image Science, and Vision·J P Thomas, L A Olzak
Dec 1, 1996·Journal of the Optical Society of America. A, Optics, Image Science, and Vision·Z L Lu, G Sperling
Sep 18, 1997·Journal of the Optical Society of America. A, Optics, Image Science, and Vision·J P Thomas, L A Olzak
Sep 18, 1997·Journal of the Optical Society of America. A, Optics, Image Science, and Vision·J Pokorny, V C Smith
Apr 16, 1998·Vision Research·S S Wolfson, M S Landy
May 18, 1999·Vision Research·L A Olzak, J P Thomas
Jun 15, 1999·Visual Neuroscience·E A Benardete, E Kaplan
Dec 10, 1999·Proceedings of the National Academy of Sciences of the United States of America·B B LeeJ Pokorny
Dec 11, 1999·Biological cybernetics·H Neumann, W Sepp

❮ Previous
Next ❯

Citations

Sep 4, 2008·Visual Neuroscience·Tim S MeeseRobert J Summers
Nov 13, 2015·Perception·Pilar Montes-LouridoF Gonzalez
Nov 10, 2005·Journal of the Optical Society of America. A, Optics, Image Science, and Vision·Lynn A Olzak, Pentti I Laurinen
Dec 23, 2003·Journal of the Optical Society of America. A, Optics, Image Science, and Vision·Steven S ShimozakiCraig K Abbey

❮ Previous
Next ❯

Related Concepts

Trending Feeds

COVID-19

Coronaviruses encompass a large family of viruses that cause the common cold as well as more serious diseases, such as the ongoing outbreak of coronavirus disease 2019 (COVID-19; formally known as 2019-nCoV). Coronaviruses can spread from animals to humans; symptoms include fever, cough, shortness of breath, and breathing difficulties; in more severe cases, infection can lead to death. This feed covers recent research on COVID-19.

Blastomycosis

Blastomycosis fungal infections spread through inhaling Blastomyces dermatitidis spores. Discover the latest research on blastomycosis fungal infections here.

Nuclear Pore Complex in ALS/FTD

Alterations in nucleocytoplasmic transport, controlled by the nuclear pore complex, may be involved in the pathomechanism underlying multiple neurodegenerative diseases including Amyotrophic Lateral Sclerosis and Frontotemporal Dementia. Here is the latest research on the nuclear pore complex in ALS and FTD.

Applications of Molecular Barcoding

The concept of molecular barcoding is that each original DNA or RNA molecule is attached to a unique sequence barcode. Sequence reads having different barcodes represent different original molecules, while sequence reads having the same barcode are results of PCR duplication from one original molecule. Discover the latest research on molecular barcoding here.

Chronic Fatigue Syndrome

Chronic fatigue syndrome is a disease characterized by unexplained disabling fatigue; the pathology of which is incompletely understood. Discover the latest research on chronic fatigue syndrome here.

Evolution of Pluripotency

Pluripotency refers to the ability of a cell to develop into three primary germ cell layers of the embryo. This feed focuses on the mechanisms that underlie the evolution of pluripotency. Here is the latest research.

Position Effect Variegation

Position Effect Variagation occurs when a gene is inactivated due to its positioning near heterochromatic regions within a chromosome. Discover the latest research on Position Effect Variagation here.

STING Receptor Agonists

Stimulator of IFN genes (STING) are a group of transmembrane proteins that are involved in the induction of type I interferon that is important in the innate immune response. The stimulation of STING has been an active area of research in the treatment of cancer and infectious diseases. Here is the latest research on STING receptor agonists.

Microbicide

Microbicides are products that can be applied to vaginal or rectal mucosal surfaces with the goal of preventing, or at least significantly reducing, the transmission of sexually transmitted infections. Here is the latest research on microbicides.

© 2022 Meta ULC. All rights reserved