What are the Mechanisms of Rivalrous First-Order and Second-Order Motions?

Perception ◽  
1996 ◽  
Vol 25 (1_suppl) ◽  
pp. 57-57 ◽  
Author(s):  
A Gellatly ◽  
A Blurton
Keyword(s):  
Motion Analysis ◽  
Visual Motion ◽  
Second Order ◽  
Differential Sensitivity ◽  
National Academy Of Sciences ◽  
First Order ◽  
Underlying Mechanisms ◽  
The Fourier Transform ◽  
Academy Of Sciences ◽  
Technical Guidance

There have been many reports in the visual motion literature describing how patterns of contrast reversal in bar stimuli may yield rivalrous motions in opposing directions. One of these, usually termed first-order motion, is generally explained in terms of ‘short range’ matching of same polarity edges or of standard motion analysis of the distribution of energy in the Fourier transform of the stimulus. The opposite, second-order, motion is usually explained in terms either of ‘long range’ matching of whole forms/features or of luminance signal rectification followed by standard motion analysis. It is known that the mechanisms underlying the two motions show differential sensitivity to manipulations of spatial frequency and eccentricity (Mather, Cavanagh, and Anstis, 1985 Perception14 163 – 166; Chubb and Sperling, 1989 Proceedings of the National Academy of Sciences of the USA86 2985 – 2989), and this paper reports a number of studies intended to further specify them in terms of their sensitivities and the interactions between them. The experiments employ mainly stimulus sequences in which luminance changes are unaccompanied by displacement of forms/features, and are designed to investigate the effects of manipulations involving the spacing of luminance events, modulations of directional power, camouflage, and attention. The results obtained raise questions about how the underlying mechanisms are best to be characterised. We are greatly indebted to Professor Ted Evans for technical guidance and assistance.

Evidence for Global Motion Interactions between First-Order and Second-Order Stimuli

Perception ◽  
1998 ◽  
Vol 27 (7) ◽  
pp. 761-767 ◽  
Author(s):  
George Mather ◽  
Linda Murdoch
Keyword(s):  
Motion Analysis ◽  
Visual Motion ◽  
Global Analysis ◽  
Image Features ◽  
Second Order ◽  
The Other ◽  
Global Motion ◽  
First Order ◽  
Motion Integration ◽  
Random Block

Recent research indicates that the early stages of visual-motion analysis involve two parallel neural pathways, one conveying information from luminance-defined (first-order) image features, the other conveying information from texture-defined (second-order) features. It is still not clear whether these two pathways converge during later stages of global motion integration. According to one account they remain segregated, and feed separate global analyses. In the alternative account, all responses feed a common stage of global analysis. Two perceptual phenomena are universally held to result from interactions between detector responses during global motion integration—direction repulsion and motion capture. We conducted two psychophysical experiments on these phenomena to test for segregation of first-order and second-order responses during integration. Stimuli contained two components, either two random-block patterns transparently drifting in different directions (repulsion measurements), or a drifting square-wave grating superimposed on an incoherent random-block pattern (capture measurements). Repulsion and capture effects were measured when both stimulus components were the same order, and when one component was first order and the other was second order. Both effects were obtained for all combinations of first-order and second-order patterns. Repulsion effects were stronger with first-order inducing patterns, and capture effects were stronger with second-order inducers. The presence of perceptual interactions regardless of stimulus order strongly suggests that responses in first-order and second-order pathways interact during global motion analysis.

An Experimental Study of Deviations from the Linear Transfer Function

1974 ◽  
Vol 32 ◽  
pp. 400-401
Author(s):  
William A. Voter ◽  
Harold P. Erickson
Keyword(s):  
Experimental Study ◽  
Image Formation ◽  
Order Theory ◽  
Second Order ◽  
Diffraction Spot ◽  
Order Effects ◽  
First Order ◽  
First Order Theory ◽  
Second Order Effects ◽  
The Fourier Transform

In a previous experimental study of image formation using a thin (20 nm) negatively stained catalase crystal, it was found that a linear or first order theory of image formation would explain almost entirely the changes in the Fourier transform of the image as a function of defocus. In this case it was concluded that the image is a valid picture of the object density. For thicker, higher contrast objects the first order theory may not be valid. Second order effects could generate false diffraction spots which would lead to spurious and artifactual image details. These second order effects would appear as deviations of the diffraction spot amplitudes from the first order theory. Small deviations were in fact noted in the study of the thin crystals, but there was insufficient data for a quantitative analysis.

Letter Reading as a Function of Approximation to English and French

1971 ◽  
Vol 33 (3_suppl) ◽  
pp. 1139-1142 ◽  
Author(s):  
Renaud S. Le Blanc ◽  
J. Gerard Muise
Keyword(s):  
French Text ◽  
English Language ◽  
Order Approximation ◽  
Second Order ◽  
Differential Sensitivity ◽  
First Order ◽  
French And English ◽  
First Order Approximation

French Ss were required to read letter strings which approximated French and English texts. Ss performed similarly at the zero and first order approximation but read faster on the French text at the second order. The results may be due to the greater uncertainty of the English language or to a differential sensitivity to the statistical constraints of both languages.

scholarly journals Processing of first- and second-order motion signals by neurons in area MT of the macaque monkey

1998 ◽  
Vol 15 (2) ◽  
pp. 305-317 ◽  
Author(s):  
LAWRENCE P. O'KEEFE ◽  
J. ANTHONY MOVSHON
Keyword(s):  
Visual Motion ◽  
Luminance Contrast ◽  
Macaque Monkey ◽  
Small Sample ◽  
Second Order ◽  
Spatial Modulation ◽  
Motion Processing ◽  
Motion Sensors ◽  
Area Mt ◽  
First Order

Extrastriate cortical area MT is thought to process behaviorally important visual motion signals. Psychophysical studies suggest that visual motion signals may be analyzed by multiple mechanisms, a “first-order” one based on luminance, and a “second-order” one based upon higher level cues (e.g. contrast, flicker). Second-order motion is visible to human observers, but should be invisible to first-order motion sensors. To learn if area MT is involved in the analysis of second-order motion, we measured responses to first- and second-order gratings of single neurons in area MT (and in one experiment, in area V1) in anesthetized, paralyzed macaque monkeys. For each neuron, we measured directional and spatio-temporal tuning with conventional first-order gratings and with second-order gratings created by spatial modulation of the flicker rate of a random texture. A minority of MT and V1 neurons exhibited significant selectivity for direction or orientation of second-order gratings. In nearly all cells, response to second-order motion was weaker than response to first-order motion. MT cells with significant selectivity for second-order motion tended to be more responsive and more sensitive to luminance contrast, but were in other respects similar to the remaining MT neurons; they did not appear to represent a distinct subpopulation. For those cells selective for second-order motion, we found a correlation between the preferred directions of first- and second-order motion, and weak correlations in preferred spatial frequency. These cells preferred lower temporal frequencies for second-order motion than for first-order motion. A small proportion of MT cells seemed to remain selective and responsive for second-order motion. None of our small sample of V1 cells did. Cells in this small population, but not others, may perform “form-cue invariant” motion processing (Albright, 1992).

scholarly journals Properties of smooth pursuit and visual motion reaction time to second-order motion stimuli

PLoS ONE ◽  
2020 ◽  
Vol 15 (12) ◽  
pp. e0243430
Author(s):  
Takeshi Miyamoto ◽  
Kenichiro Miura ◽  
Tomohiro Kizuka ◽  
Seiji Ono
Keyword(s):  
Reaction Time ◽  
Motion Perception ◽  
Smooth Pursuit ◽  
Visual Motion ◽  
Second Order ◽  
Image Motion ◽  
Visual Motion Perception ◽  
First Order ◽  
Pursuit Initiation ◽  
Neurophysiological Studies

A large number of psychophysical and neurophysiological studies have demonstrated that smooth pursuit eye movements are tightly related to visual motion perception. This could be due to the fact that visual motion sensitive cortical areas such as meddle temporal (MT), medial superior temporal (MST) areas are involved in motion perception as well as pursuit initiation. Although the directional-discrimination and perceived target velocity tasks are used to evaluate visual motion perception, it is still uncertain whether the speed of visual motion perception, which is determined by visuomotor reaction time (RT) to a small target, is related to pursuit initiation. Therefore, we attempted to determine the relationship between pursuit latency/acceleration and the visual motion RT which was measured to the visual motion stimuli that moved leftward or rightward. The participants were instructed to fixate on a stationary target and press one of the buttons corresponding to the direction of target motion as soon as possible once the target starts to move. We applied five different visual motion stimuli including first- and second-order motion for smooth pursuit and visual motion RT tasks. It is well known that second-order motion induces lower retinal image motion, which elicits weaker responses in MT and MST compared to first-order motion stimuli. Our results showed that pursuit initiation including latency and initial eye acceleration were suppressed by second-order motion. In addition, second-order motion caused a delay in visual motion RT. The better performances in both pursuit initiation and visual motion RT were observed for first-order motion, whereas second-order (theta motion) induced remarkable deficits in both variables. Furthermore, significant Pearson’s correlation and within-subjects correlation coefficients were obtained between visual motion RT and pursuit latency/acceleration. Our findings support the suggestion that there is a common neuronal pathway involved in both pursuit initiation and the speed of visual motion perception.

Nonlinear Analysis of Visual Evoked Potentials Elicited by Color Stimulation

1997 ◽  
Vol 36 (04/05) ◽  
pp. 315-318 ◽  
Author(s):  
K. Momose ◽  
K. Komiya ◽  
A. Uchiyama
Keyword(s):  
Visual System ◽  
Evoked Potentials ◽  
Visual Evoked Potentials ◽  
Normal Subjects ◽  
Second Order ◽  
First Order ◽  
The Relationship ◽  
Perceived Color ◽  
Second Order Nonlinearity ◽  
Visual Evoked

Abstract:The relationship between chromatically modulated stimuli and visual evoked potentials (VEPs) was considered. VEPs of normal subjects elicited by chromatically modulated stimuli were measured under several color adaptations, and their binary kernels were estimated. Up to the second-order, binary kernels obtained from VEPs were so characteristic that the VEP-chromatic modulation system showed second-order nonlinearity. First-order binary kernels depended on the color of the stimulus and adaptation, whereas second-order kernels showed almost no difference. This result indicates that the waveforms of first-order binary kernels reflect perceived color (hue). This supports the suggestion that kernels of VEPs include color responses, and could be used as a probe with which to examine the color visual system.

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