What is the Transition Point between Static and Dynamic Motion Aftereffects?

Perception ◽  
1997 ◽  
Vol 26 (1_suppl) ◽  
pp. 75-75
Author(s):  
H Ashida ◽  
F A J Verstraten ◽  
S Nishida
Keyword(s):  
Transition Point ◽  
Test Pattern ◽  
Dynamic Properties ◽  
Temporal Frequency ◽  
Dynamic Test ◽  
Interocular Transfer ◽  
Second Order ◽  
Adaptation Stimulus ◽  
Static Test ◽  
First Order

The motion aftereffect (MAE) measured with a dynamic test pattern (eg a counterphase-flickering grating) is distinguishable by a number of properties from the classical MAE obtained with a static test pattern. For a dynamic MAE, however, it is not sufficient simply to introduce dynamic properties into the test pattern. In two experiments we attempted to determine the transition point in the temporal-frequency domain at which a dynamic MAE becomes distinguishable from the static MAE. First, we examined the interocular transfer (IOT) of the MAE with conventional first-order (luminance) gratings. The amount of IOT increased with temporal frequency, and was almost complete at 1 Hz and above. In addition, the IOT of a dynamic MAE shows a drastic reduction in the peripheral visual field, possibly reflecting difficulties in feature tracking or the loss of involuntary attention. Second, we examined the MAE with second-order motion as the adaptation stimulus (contrast modulation of two-dimensional static noise). Under these conditions, similar results were obtained for first-order and second-order test gratings: MAE was not observed at low temporal frequencies and a substantial MAE was observed only at 1 Hz and above. The results agree with recent findings which showed a gradual loss of spatial-frequency selectivity with increasing temporal frequency of the test pattern (Mareschal et al, 1997 Vision Research37 1755 – 1759). The present results support the idea that two mechanisms underlie the different kinds of MAE: a low-level mechanism responsible for the MAE observed at low temporal frequencies, and a high-level mechanism operating predominantly at high temporal frequencies with a transition point at about 1 Hz.

scholarly journals Velocity Dependence of the Interocular Transfer of Dynamic Motion Aftereffects

Perception ◽  
10.1068/p3442 ◽  
2003 ◽  
Vol 32 (7) ◽  
pp. 855-866 ◽  
Author(s):  
Ran Tao ◽  
Martin J M Lankheet ◽  
Wim A van de Grind ◽  
Richard J A van Wezel
Keyword(s):  
Signal To Noise Ratio ◽  
Dominant Role ◽  
Dynamic Test ◽  
Interocular Transfer ◽  
Adaptation Stimulus ◽  
Motion Adaptation ◽  
Pixel Array ◽  
Noise Test ◽  
Motion Aftereffects ◽  
Measured Strength

It is well established that motion aftereffects (MAEs) can show interocular transfer (IOT); that is, motion adaptation in one eye can give a MAE in the other eye. Different quantification methods and different test stimuli have been shown to give different IOT magnitudes, varying from no to almost full IOT. In this study, we examine to what extent IOT of the dynamic MAE (dMAE), that is the MAE seen with a dynamic noise test pattern, varies with velocity of the adaptation stimulus. We measured strength of dMAE by a nulling method. The aftereffect induced by adaptation to a moving random-pixel array was compensated (nulled), during a brief dynamic test period, by the same kind of motion stimulus of variable luminance signal-to-noise ratio (LSNR). The LSNR nulling value was determined in a Quest-staircase procedure. We found that velocity has a strong effect on the magnitude of IOT for the dMAE. For increasing speeds from 1.5 deg s−1 to 24 deg s−1 average IOT values increased about linearly from 18% to 63% or from 32% to 83%, depending on IOT definition. The finding that dMAEs transfer to an increasing extent as speed increases, suggests that binocular cells play a more dominant role at higher speeds.

The Duration of the Motion Aftereffect following Adaptation to First-Order and Second-Order Motion

Perception ◽  
1994 ◽  
Vol 23 (10) ◽  
pp. 1211-1219 ◽  
Author(s):  
Timothy Ledgeway ◽  
Andrew T Smith
Keyword(s):  
Motion Aftereffect ◽  
Second Order ◽  
Adaptation Stimulus ◽  
Motion Patterns ◽  
First Order ◽  
Parallel Motion ◽  
Significant Difference ◽  
Cross Adaptation ◽  
Identification Threshold ◽  
Direction Opposite

The magnitude of the motion aftereffect (MAE) obtained following adaptation to first-order or to second-order motion was measured by estimating its duration. The second-order adaptation stimulus was composed of contrast-modulated noise produced by multiplying two-dimensional (2-D) noise by a drifting 1 cycle deg−1 sine grating. The first-order adaptation stimulus was composed of luminance-modulated noise produced by summing, rather than multiplying, the noise and the sine grating. The test stimuli were directionally ambiguous motion patterns composed of either two oppositely drifting sine gratings added to noise or the contrast-modulated equivalent. The adaptation and test stimuli were equated for visibility by presenting them at the same multiple of direction-identification threshold. All possible combinations of first-order and second-order adaptation and test stimuli were examined in order to compare the magnitudes of the MAEs obtained following same adaptation and cross adaptation. After adaptation the test stimuli always appeared to drift coherently in the direction opposite to that of adaptation and the magnitudes of this MAE were very similar for all conditions examined. Statistical analyses of the results showed that there was no significant difference between the durations of the MAEs obtained in the same-adaptation and cross-adaptation conditions. The cross-adaptation effects suggest that either first-order or second-order motion are detected by a common low-level mechanism, or that separate parallel motion-detecting mechanisms exist, for the two types of motion, that interact at some later stage of processing.

scholarly journals Effect of the Elastomer Matrix on Thermoplastic Elastomer-Based Strain Sensor Fiber Composites

Sensors ◽  
2020 ◽  
Vol 20 (8) ◽  
pp. 2399 ◽  
Author(s):  
Antonia Georgopoulou ◽  
Claudia Kummerlöwe ◽  
Frank Clemens
Keyword(s):  
Natural Rubber ◽  
Soft Matter ◽  
Dynamic Properties ◽  
Matrix Material ◽  
Dynamic Test ◽  
Thermoplastic Elastomer ◽  
Static Test ◽  
The Matrix ◽  
Sensor Properties ◽  
Different Strains

In this study, a thermoplastic elastomer sensor fiber was embedded in an elastomer matrix. The effect of the matrix material on the sensor properties and the piezoresistive behavior of the single fiber-matrix composite system was investigated. For all composites, cycling test (dynamic test) and the relaxation behavior at different strains (quasi-static test) were investigated. In all cases, dynamic properties and quasi-static significantly changed after embedding, compared to the pure fiber. The composite with the silicone elastomer PDMS (Polydimethylsiloxane) as matrix material exhibited deviation from linear response of the resistivity at low strains and proved an unsuitable choice compared to natural rubber. The addition of a spring construct in the embedded sensor fiber natural rubber composite improved the linearity at low strains but increased the mechanical and electrical hysteresis of the soft matter sensor composite. Using pre-vulcanized natural rubber improved linearity at low strains and reduced significantly the stress and relative resistance relaxation as well as the resistance hysteresis, especially if the resistance remained low. In both cases of the pre-vulcanized rubber and the spring structure, the piezoresistive behavior was improved, and at the same time, the stiffness of the system was increased indicating that using a stiffer matrix can be a strategy for improving the sensor properties.

scholarly journals Thermodynamic phase transition and global stability of the regular Hayward black hole surrounded by quintessence

2020 ◽  
Vol 35 (16) ◽  
pp. 2050129
Author(s):  
Kamiko Kouemeni Jean Rodrigue ◽  
Mahamat Saleh ◽  
Bouetou Bouetou Thomas ◽  
Kofane Timoleon Crepin
Keyword(s):  
Phase Transition ◽  
Black Hole ◽  
Transition Point ◽  
Second Order ◽  
Hawking Temperature ◽  
Unstable State ◽  
Second Phase ◽  
Normalization Factor ◽  
First Order ◽  
Transition Points

In this work, we investigate the thermodynamic and the stability of the regular Hayward black hole surrounded by quintessence. Using the metric of the black hole surrounded by quintessence and the new approach of the holographic principle, we derive the expression of the Unruh–Verlinde temperature. Hawking temperature and specific heat are derived using the first law of black holes thermodynamics. Gibbs free energy is also evaluated. The behaviors of these quantities show that, the parameter of the regular Hayward black hole [Formula: see text] induces a decreasing of the Hawking temperature of the black hole, and that decrease is accentuated when increasing the magnitude of [Formula: see text] and the normalization factor related to the density of quintessence. For the lower entropies, the black hole passes from the unstable phase to the stable one by a first-order thermodynamics phase transition. When increasing the entropy, a second phase transition occurs. This new phase transition is a second-order thermodynamics phase transition and brings the black hole to unstable state. It results that, when increasing of magnitude of [Formula: see text], the phase transition points are shifted to the higher entropies. Moreover, the phenomena of phase transitions are preserved by adding the quintessence. Furthermore, when increasing the normalization factor of quintessence, the first-order transition point is shifted to higher entropies, while the second-order thermodynamics phase transition point is shifted to lower entropies.

scholarly journals Aftereffect of High-Speed Motion

Perception ◽  
1998 ◽  
Vol 27 (9) ◽  
pp. 1055-1066 ◽  
Author(s):  
Frans A J Verstraten ◽  
Maarten J van der Smagt ◽  
Wim A van de Grind
Keyword(s):  
High Speed ◽  
Test Pattern ◽  
Dynamic Test ◽  
Motion Aftereffect ◽  
Motion Sensors ◽  
Static Test ◽  
High Speeds ◽  
Test Conditions ◽  
Motion Aftereffects ◽  
Determining Factor

A visual illusion known as the motion aftereffect is considered to be the perceptual manifestation of motion sensors that are recovering from adaptation. This aftereffect can be obtained for a specific range of adaptation speeds with its magnitude generally peaking for speeds around 3 deg s−1. The classic motion aftereffect is usually measured with a static test pattern. Here, we measured the magnitude of the motion aftereffect for a large range of velocities covering also higher speeds, using both static and dynamic test patterns. The results suggest that at least two (sub)populations of motion-sensitive neurons underlie these motion aftereffects. One population shows itself under static test conditions and is dominant for low adaptation speeds, and the other is prevalent under dynamic test conditions after adaptation to high speeds. The dynamic motion aftereffect can be perceived for adaptation speeds up to three times as fast as the static motion aftereffect. We tested predictions that follow from the hypothesised division in neuronal substrates. We found that for exactly the same adaptation conditions (oppositely directed transparent motion with different speeds), the aftereffect direction differs by 180° depending on the test pattern. The motion aftereffect is opposite to the pattern moving at low speed when the test pattern is static, and opposite to the high-speed pattern for a dynamic test pattern. The determining factor is the combination of adaptation speed and type of test pattern.

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.

Imaginings

2017 ◽  
Vol 9 (3) ◽  
pp. 17-30
Author(s):  
Kelly James Clark
Keyword(s):  
Religious Tradition ◽  
Second Order ◽  
Fine Tuning ◽  
Intellectual Humility ◽  
First Order ◽  
Natural Processes ◽  
Empirically Supported ◽  
Group Violence ◽  
The World ◽  
The Universe

In Branden Thornhill-Miller and Peter Millican’s challenging and provocative essay, we hear a considerably longer, more scholarly and less melodic rendition of John Lennon’s catchy tune—without religion, or at least without first-order supernaturalisms (the kinds of religion we find in the world), there’d be significantly less intra-group violence. First-order supernaturalist beliefs, as defined by Thornhill-Miller and Peter Millican (hereafter M&M), are “beliefs that claim unique authority for some particular religious tradition in preference to all others” (3). According to M&M, first-order supernaturalist beliefs are exclusivist, dogmatic, empirically unsupported, and irrational. Moreover, again according to M&M, we have perfectly natural explanations of the causes that underlie such beliefs (they seem to conceive of such natural explanations as debunking explanations). They then make a case for second-order supernaturalism, “which maintains that the universe in general, and the religious sensitivities of humanity in particular, have been formed by supernatural powers working through natural processes” (3). Second-order supernaturalism is a kind of theism, more closely akin to deism than, say, Christianity or Buddhism. It is, as such, universal (according to contemporary psychology of religion), empirically supported (according to philosophy in the form of the Fine-Tuning Argument), and beneficial (and so justified pragmatically). With respect to its pragmatic value, second-order supernaturalism, according to M&M, gets the good(s) of religion (cooperation, trust, etc) without its bad(s) (conflict and violence). Second-order supernaturalism is thus rational (and possibly true) and inconducive to violence. In this paper, I will examine just one small but important part of M&M’s argument: the claim that (first-order) religion is a primary motivator of violence and that its elimination would eliminate or curtail a great deal of violence in the world. Imagine, they say, no religion, too.Janusz Salamon offers a friendly extension or clarification of M&M’s second-order theism, one that I think, with emendations, has promise. He argues that the core of first-order religions, the belief that Ultimate Reality is the Ultimate Good (agatheism), is rational (agreeing that their particular claims are not) and, if widely conceded and endorsed by adherents of first-order religions, would reduce conflict in the world.While I favor the virtue of intellectual humility endorsed in both papers, I will argue contra M&M that (a) belief in first-order religion is not a primary motivator of conflict and violence (and so eliminating first-order religion won’t reduce violence). Second, partly contra Salamon, who I think is half right (but not half wrong), I will argue that (b) the religious resources for compassion can and should come from within both the particular (often exclusivist) and the universal (agatheistic) aspects of religious beliefs. Finally, I will argue that (c) both are guilty, as I am, of the philosopher’s obsession with belief. 

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