title: Binocular combination of phase and contrast explained by a gain-control and gain-enhancement model.
abstract: We investigated suprathreshold binocular combination, measuring both the perceived phase and perceived contrast of a cyclopean sine wave. We used a paradigm adapted from Ding and Sperling (2006, 2007) to measure the perceived phase by indicating the apparent location (phase) of the dark trough in the horizontal cyclopean sine wave relative to a black horizontal reference line, and we used the same stimuli to measure perceived contrast by matching the binocular combined contrast to a standard contrast presented to one eye. We found that under normal viewing conditions (high contrast and long stimulus duration), perceived contrast is constant, independent of the interocular contrast ratio and the interocular phase difference, while the perceived phase shifts smoothly from one eye to the other eye depending on the contrast ratios. However, at low contrasts and short stimulus durations, binocular combination is more linear and contrast summation is phase-dependent. To account for phase-dependent contrast summation, we incorporated a fusion remapping mechanism into our model, using disparity energy to shift the monocular phases towards the cyclopean phase in order to align the two eyes' images through motor/sensory fusion. The Ding-Sperling model with motor/sensory fusion mechanism gives a reasonable account of the phase dependence of binocular contrast combination and can account for either the perceived phase or the perceived contrast of a cyclopean sine wave separately; however it requires different model parameters for the two. However, when fit to both phase and contrast data simultaneously, the Ding-Sperling model fails. Incorporating interocular gain enhancement into the model results in a significant improvement in fitting both phase and contrast data simultaneously, successfully accounting for both linear summation at low contrast energy and strong nonlinearity at high contrast energy.
authors: School of Optometry and the Helen Wills Neuroscience Institute, University of California, Berkeley, Berkeley, CA, USA. jian.ding@berkeley.edu
authors: Jian
authors: J
authors: Ding
authors: Stanley A
authors: SA
authors: Klein
authors: Dennis M
authors: DM
authors: Levi
mesh_terms: D015350:Contrast Sensitivity / Q000502:physiology*; D006801:Humans; D008962:Models, Theoretical; D013997:Time Factors; D015348:Vision, Binocular / Q000502:physiology*; D014793:Visual Cortex / Q000502:physiology*
references: Vision Res. 2011 Apr 13;51(7):754-70
references: 20951722
references: Vision Res. 1994 Jan;34(1):19-29
references: 8116265
references: Vision Res. 2007 Feb;47(4):479-500
references: 17118422
references: Vision Res. 1993 Aug;33(12):1685-95
references: 8236856
references: Vision Res. 1984;24(4):385-94
references: 6740959
references: J Vis. 2004 Oct 18;4(10):843-59
references: 15595890
references: Spat Vis. 2007;20(5):397-413
references: 17716525
references: PLoS One. 2010 Dec 09;5(12):e15075
references: 21151558
references: J Vis. 2013 Feb 08;13(2):14
references: 23397039
references: Spat Vis. 1997;10(4):437-42
references: 9176953
references: J Vis. 2009 Mar 24;9(3):17.1-16
references: 19757956
references: Vision Res. 1984;24(7):661-5
references: 6464360
references: Vision Res. 1985;25(9):1223-32
references: 4072001
references: J Vis. 2011 May 05;11(6):
references: 21546609
references: Vision Res. 1984;24(4):373-83
references: 6740958
references: Vision Res. 2001 Mar;41(5):571-83
references: 11226503
references: Vision Res. 1991;31(7-8):1337-50
references: 1891822
references: J Vis. 2009 Mar 20;9(3):13.1-22
references: 19757952
references: Vision Res. 2006 Oct;46(21):3723-40
references: 16765403
references: Percept Psychophys. 1981 Jul;30(1):49-61
references: 7290896
references: Percept Psychophys. 1981 Sep;30(3):266-76
references: 7322802
references: Vision Res. 1989;29(9):1115-32
references: 2617860
references: Proc Natl Acad Sci U S A. 2006 Jan 24;103(4):1141-6
references: 16410354
references: Vision Res. 1998 Feb;38(3):411-21
references: 9536364
references: J Vis. 2006 Oct 23;6(11):1224-43
references: 17209731
references: J Opt Soc Am A. 1991 Apr;8(4):673-80
references: 2045969
references: Proc Natl Acad Sci U S A. 2003 Nov 25;100(24):14499-503
references: 14612564
references: Nature. 1997 Sep 18;389(6648):283-6
references: 9305842
references: Kybernetik. 1968 Apr;4(4):146-56
references: 4973310
references: Vision Res. 1998 Sep;38(18):2711-9
references: 9775320
references: Science. 1976 May 7;192(4239):561-3
references: 1257791
references: Vision Res. 1996 Jan;36(1):27-41
references: 8746240
references: Percept Psychophys. 2001 Nov;63(8):1421-55
references: 11800466
references: PLoS One. 2012;7(4):e34696
references: 22485185
references: Vision Res. 1981;21(4):457-67
references: 7269325
references: J Opt Soc Am. 1983 Dec;73(12):1665-73
references: 6663369
references: J Neurophysiol. 2001 Mar;85(3):1129-52
references: 11247983
references: Optom Vis Sci. 2000 Jun;77(6):309-20
references: 10879788
references: Spat Vis. 1997;10(4):433-6
references: 9176952
references: Nature. 1965 Oct 9;208(5006):191-2
references: 5884255
references: Vision Res. 2008 Aug;48(17):1837-51
references: 18585750
references: Vision Res. 1994 Sep;34(17):2317-29
references: 7941424
references: Ann N Y Acad Sci. 2005 Apr;1039:252-9
references: 15826979
references: Vision Res. 2006 Jul;46(15):2456-64
references: 16530243
references: Vision Res. 1987;27(12):2125-39
references: 3447362