-
Neural Networks : the Official Journal... Jul 2015Although numerous models describe the individual neural mechanisms that may be involved in the perception of visual motion, few of them have been constructed to take...
Although numerous models describe the individual neural mechanisms that may be involved in the perception of visual motion, few of them have been constructed to take arbitrary stimuli and map them to a motion percept. Here, we propose an integrated dynamical motion model (IDM), which is sufficiently general to handle diverse moving stimuli, yet sufficiently precise to account for a wide-ranging set of empirical observations made on a family of random dot kinematograms. In particular, we constructed models of the cortical areas involved in motion detection, motion integration and perceptual decision. We analyzed their parameters through dynamical simulations and numerical continuation to constrain their proper ranges. Then, empirical data from a family of random dot kinematograms experiments with systematically varying direction distribution, presentation duration and stimulus size, were used to evaluate our model and estimate corresponding model parameters. The resulting model provides an excellent account of a demanding set of parametrically varied behavioral effects on motion perception, providing both quantitative and qualitative elements of evaluation.
Topics: Algorithms; Humans; Models, Neurological; Motion; Motion Perception; Visual Fields; Visual Perception
PubMed: 25897511
DOI: 10.1016/j.neunet.2015.03.011 -
Annual Review of Vision Science Oct 2016This review discusses several pervasive myths about peripheral vision, as well as what is actually true: Peripheral vision underlies a broad range of visual tasks, in... (Review)
Review
This review discusses several pervasive myths about peripheral vision, as well as what is actually true: Peripheral vision underlies a broad range of visual tasks, in spite of its significant loss of information. New understanding of peripheral vision, including likely mechanisms, has deep implications for our understanding of vision. From peripheral recognition to visual search, from change blindness to getting the gist of a scene, a lossy but relatively fixed peripheral encoding may determine the difficulty of many tasks. This finding suggests that the visual system may be more stable, and less dynamically changing as a function of attention, than previously assumed.
Topics: Attention; Humans; Pattern Recognition, Visual; Visual Acuity; Visual Fields; Visual Perception
PubMed: 28532349
DOI: 10.1146/annurev-vision-082114-035733 -
Journal of Neurology, Neurosurgery, and... Oct 1963
Topics: Afterimage; Brain Diseases; Flicker Fusion; Humans; Vision Tests; Vision, Ocular; Visual Perception
PubMed: 14066640
DOI: 10.1136/jnnp.26.5.468 -
Perception 1998
Topics: Afterimage; Flicker Fusion; Form Perception; Humans; Models, Biological; Visual Perception
PubMed: 9692084
DOI: 10.1068/p270003 -
Science (New York, N.Y.) May 1988Anatomical and physiological observations in monkeys indicate that the primate visual system consists of several separate and independent subdivisions that analyze... (Review)
Review
Anatomical and physiological observations in monkeys indicate that the primate visual system consists of several separate and independent subdivisions that analyze different aspects of the same retinal image: cells in cortical visual areas 1 and 2 and higher visual areas are segregated into three interdigitating subdivisions that differ in their selectivity for color, stereopsis, movement, and orientation. The pathways selective for form and color seem to be derived mainly from the parvocellular geniculate subdivisions, the depth- and movement-selective components from the magnocellular. At lower levels, in the retina and in the geniculate, cells in these two subdivisions differ in their color selectivity, contrast sensitivity, temporal properties, and spatial resolution. These major differences in the properties of cells at lower levels in each of the subdivisions led to the prediction that different visual functions, such as color, depth, movement, and form perception, should exhibit corresponding differences. Human perceptual experiments are remarkably consistent with these predictions. Moreover, perceptual experiments can be designed to ask which subdivisions of the system are responsible for particular visual abilities, such as figure/ground discrimination or perception of depth from perspective or relative movement--functions that might be difficult to deduce from single-cell response properties.
Topics: Animals; Color Perception; Depth Perception; Form Perception; Humans; Motion Perception; Visual Pathways; Visual Perception
PubMed: 3283936
DOI: 10.1126/science.3283936 -
Cognition May 2024The independent effects of short- and long-term experiences on visual perception have been discussed for decades. However, no study has investigated whether and how...
The independent effects of short- and long-term experiences on visual perception have been discussed for decades. However, no study has investigated whether and how these experiences simultaneously affect our visual perception. To address this question, we asked participants to estimate their self-motion directions (i.e., headings) simulated from optic flow, in which a long-term experience learned in everyday life (i.e., straight-forward motion being more common than lateral motion) plays an important role. The headings were selected from three distributions that resembled a peak, a hill, and a flat line, creating different short-term experiences. Importantly, the proportions of headings deviating from the straight-forward motion gradually increased in the peak, hill, and flat distributions, leading to a greater conflict between long- and short-term experiences. The results showed that participants biased their heading estimates towards the straight-ahead direction and previously seen headings, which increased with the growing experience conflict. This suggests that both long- and short-term experiences simultaneously affect visual perception. Finally, we developed two Bayesian models (Model 1 vs. Model 2) based on two assumptions that the experience conflict altered the likelihood distribution of sensory representation or the motor response system. The results showed that both models accurately predicted participants' estimation biases. However, Model 1 predicted a higher variance of serial dependence compared to Model 2, while Model 2 predicted a higher variance of the bias towards the straight-ahead direction compared to Model 1. This suggests that the experience conflict can influence visual perception by affecting both sensory and motor response systems. Taken together, the current study systematically revealed the effects of long- and short-term experiences on visual perception and the underlying Bayesian processing mechanisms.
Topics: Humans; Motion Perception; Bayes Theorem; Visual Perception; Learning; Optic Flow
PubMed: 38479091
DOI: 10.1016/j.cognition.2024.105768 -
Nature Jan 1995How does the human visual system 'bind' different fragments in the visual scene to create enduring representations of objects? A visual illusion known as 'metacontrast'...
How does the human visual system 'bind' different fragments in the visual scene to create enduring representations of objects? A visual illusion known as 'metacontrast' or backward masking provides compelling evidence that perception is not instantaneous and that it occurs sequentially in distinct stages. If a solid white target square is displayed for 50 ms in a tachistoscope, switched off, and followed by a 50 ms display of two flanking mask squares, remarkably, subjects report seeing only the two flanking squares: the first square is simply not 'seen'. By plotting the magnitude of masking as a function of the delay between the target and mask (the stimulus onset asynchrony), one can obtain a characteristic 'U'-shaped function with optimum masking occurring at about 50 ms, and no masking with synchronous target and mask presentations or at delays higher than 300 ms. The illusion is also highly sensitive to elementary stimulus dimensions such as colour, orientation and spatial frequency, and it has been suggested that it is based on 'low level' autonomous visual mechanisms rather than cognitive processes. Here we describe a novel visual stimulus that demonstrates that metacontrast can be strongly modulated by 'top down' influence such as voluntary visual attention.
Topics: Attention; Contrast Sensitivity; Humans; Motion Perception; Optical Illusions; Time Perception; Visual Perception
PubMed: 7800040
DOI: 10.1038/373066a0 -
The Harvard Mental Health Letter Nov 2010
Topics: Color Perception; Contrast Sensitivity; Depressive Disorder, Major; Humans; Retina; Visual Perception
PubMed: 21222289
DOI: No ID Found -
Perceptual and Motor Skills Jun 1983This paper examined effects of sports practice on patterns of color fields, limits of peripheral movement perception, and visual acuity field by comparing varsity ball...
This paper examined effects of sports practice on patterns of color fields, limits of peripheral movement perception, and visual acuity field by comparing varsity ball players and non-varsity control groups. The first study measured extent of color fields and limits of horizontal and vertical meridians for peripheral movement perception of 139 college students. The second study tested visual acuity fields of female and male basketball players and female and male controls. The first study indicated that athletes had wider limits for horizontal movement perception, while the non-athletes had better vertical movement perception limits. Basketball players demonstrated color fields and limits for peripheral movement perception superior to those of soccer players. In the second study, athletes did not have any wider visual acuity fields than non-athletes, but their movement-perception limits were significantly wider than those of non-athletes.
Topics: Color Perception; Female; Humans; Male; Motion Perception; Sex Factors; Soccer; Sports; Sports Medicine; Visual Acuity; Visual Fields; Visual Perception
PubMed: 6877976
DOI: 10.2466/pms.1983.56.3.887 -
Journal of Experimental Psychology Nov 1962
Topics: Color; Color Perception; Humans; Visual Perception
PubMed: 13989583
DOI: 10.1037/h0047634