(from abstract): A thorough understanding of visual information processing is important not only because vision is the largest source of sensory input to the nervous system, but also because the visual system is a model for neural information processing in general. The proposed research continues our attempts to advance the understanding of complex visual processing, with an emphasis on the relationship of local feature extraction to the longer-range processes that are involved in image segmentation and object recognition. The project has three goals: to determine the dynamics of the computations involved in vernier acuity, to determine the dynamics of the computations involved in illusory contour formation, and to understand their mechanism and relationship. For both vernier acuity and illusory contour formation, we make use of a framework dynamical model. This model guides the exploration of critical stimulus parameters (such as temporal frequency and temporal phase of stimulus components) and provides a rigorous way to compare the dynamics of the two processes. We anticipate that these dynamics will be rather different, and the later experiments will isolate various spatial aspects of the stimuli, in order to understand the basis for this difference. Vernier acuity and illusory contour formation both depend critically on stimulus geometry. Current psychophysical evidence is relatively limited, but suggests that only the short-range hyperacuity phenomena depend critically on stimulus timing. This is, at least superficially, at variance with the increasingly popular notion that some kind of neural synchronization, in addition to traditional nonlinearities, form the physiological basis for the perceptual binding of components of a stimulus into a single object. Our approach, which combines psychophysics, visual evoked potentials, and modeling, will delineate both traditional nonlinearities and, should they exist, stimulus-dependent oscillations and related phenomena. This detailed analysis of the dynamics of neural computations is likely to advance our understanding of how visual perception occurs.

Agency
National Institute of Health (NIH)
Institute
National Eye Institute (NEI)
Type
Research Project (R01)
Project #
5R01EY007977-10
Application #
2634409
Study Section
Visual Sciences B Study Section (VISB)
Project Start
1989-01-01
Project End
2001-12-31
Budget Start
1998-01-01
Budget End
1998-12-31
Support Year
10
Fiscal Year
1998
Total Cost
Indirect Cost
Name
Weill Medical College of Cornell University
Department
Neurology
Type
Schools of Medicine
DUNS #
201373169
City
New York
State
NY
Country
United States
Zip Code
10065
Rucci, Michele; Victor, Jonathan D (2018) Perspective: Can eye movements contribute to emmetropization? J Vis 18:10
Victor, Jonathan D; Conte, Mary M; Chubb, Charles F (2017) Textures as Probes of Visual Processing. Annu Rev Vis Sci 3:275-296
Boi, Marco; Poletti, Martina; Victor, Jonathan D et al. (2017) Consequences of the Oculomotor Cycle for the Dynamics of Perception. Curr Biol 27:1268-1277
Victor, Jonathan D; Rizvi, Syed M; Conte, Mary M (2017) Two representations of a high-dimensional perceptual space. Vision Res 137:1-23
Joukes, Jeroen; Yu, Yunguo; Victor, Jonathan D et al. (2017) Recurrent Network Dynamics; a Link between Form and Motion. Front Syst Neurosci 11:12
Hu, Qin; Victor, Jonathan D (2016) Two-Dimensional Hermite Filters Simplify the Description of High-Order Statistics of Natural Images. Symmetry (Basel) 8:
Nitzany, Eyal I; Loe, Maren E; Palmer, Stephanie E et al. (2016) Perceptual interaction of local motion signals. J Vis 16:22
Victor, Jonathan D; Thengone, Daniel J; Rizvi, Syed M et al. (2015) A perceptual space of local image statistics. Vision Res 117:117-35
Rucci, Michele; Victor, Jonathan D (2015) The unsteady eye: an information-processing stage, not a bug. Trends Neurosci 38:195-206
Aytekin, Murat; Victor, Jonathan D; Rucci, Michele (2014) The visual input to the retina during natural head-free fixation. J Neurosci 34:12701-15

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