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.

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.

fMRI Adaptation Reveals Separate Mechanisms for First-Order and Second-Order Motion

2007 ◽  
Vol 97 (2) ◽  
pp. 1319-1325 ◽  
Author(s):  
Hiroshi Ashida ◽  
Angelika Lingnau ◽  
Matthew B. Wall ◽  
Andrew T. Smith
Keyword(s):  
Selective Adaptation ◽  
Second Order ◽  
Neural Mechanisms ◽  
Human Vision ◽  
Image Motion ◽  
First Order ◽  
Single Mechanism ◽  
Neural Populations ◽  
Cross Adaptation ◽  
Fmri Adaptation

A key unresolved debate in human vision concerns whether we have two different low-level mechanisms for encoding image motion. Separate neural mechanisms have been suggested for first-order (luminance modulation) and second-order (e.g., contrast modulation) motion in the retinal image but a single mechanism could handle both. Human functional magnetic resonance imaging (fMRI) has not so far convincingly revealed separate anatomical substrates. To examine whether two separate but co-localized mechanisms might exist, we used the technique of fast fMRI adaptation. We found direction-selective adaptation independently for each type of motion in the motion area V5/MT+ of the human brain. However, there was a total absence of cross-adaptation between first-order and second-order motion stimuli. This was true in both of the two subcomponents of MT+ (MT and MST) and similar results were found in V3A. This pattern of adaptation was consistent with psychophysical measurements of detection thresholds in similar stimulus sequences. The results provide strong evidence for separate neural populations that are responsible for detecting first- and second-order motion.

scholarly journals Theory of Mind Deficits and Their Influence on Functional Impairment in Remitted Phase of Bipolar Disorder

2020 ◽  
pp. 025371762093031
Author(s):  
Pradeep Palaniappan ◽  
Krishnapriya Easwaran
Keyword(s):  
Bipolar Disorder ◽  
Theory Of Mind ◽  
Functional Impairment ◽  
Second Order ◽  
Or Education ◽  
Global Functioning ◽  
First Order ◽  
Significant Difference ◽  
Depressive Episodes ◽  
Illness Variables

Background: Functional impairment has been convincingly established in the euthymic/ remitted phase of bipolar disorder (BD). Though deficits in social cognition, especially theory of mind (ToM), predict functional impairment, the association has not been consistently proven. Methods: Thirty remitted subjects with BD (as per DSM 5) and 30 age- and gender-matched healthy controls were screened for eligibility and the sociodemographic details and ToM scores, that is, first-order ToM, second-order ToM, and Faux pas, were collected. In subjects with BD, functioning was assessed using Functioning Assessment Short Test (FAST) and illness variables were collected. Results: No significant difference was found in occupation or education between the groups. Remitted subjects with BD had statistically significant deficits in all domains of ToM, that is, first-order ToM ( r = 0.65), second-order ToM ( r = 0.69), and Faux pas ( r = 0.75). Significant correlations existed between first-order ToM and FAST total score, as well as second-order ToM and FAST total score, but the correlations dropped after controlling for duration of illness and number of depressive episodes. Quantile regression analysis showed that the only factors which predicted global functional impairment was a higher number of episodes ( βτ= –0.45, SE = 3.51, t = 0.13, P = 0.04), while all other illness variables and ToM failed to predict the global functioning. Conclusion: Though there seems to be an association between ToM and functioning, only illness variables predicted functional impairment in subjects with BD. We need prospective studies to delineate the contributors to functional impairment.

scholarly journals Motion Aftereffect of Combined First-Order and Second-Order Motion

Perception ◽  
10.1068/p2899 ◽  
1999 ◽  
Vol 28 (11) ◽  
pp. 1397-1411 ◽  
Author(s):  
Maarten J van der Smagt ◽  
Frans A J Verstraten ◽  
Eric B P Vaessen ◽  
Thomas van Londen ◽  
Wim A van de Grind
Keyword(s):  
Motion Aftereffect ◽  
Second Order ◽  
First Order

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. 

Evidence for general base catalysis by protic solvents in a kinetic study of alcoholyses and hydrolyses of 1-(phenoxycarbonyl)pyridinium ions under both solvolytic and non-solvolytic conditions

2009 ◽  
Vol 74 (1) ◽  
pp. 43-55 ◽  
Author(s):  
Dennis N. Kevill ◽  
Byoung-Chun Park ◽  
Jin Burm Kyong
Keyword(s):  
Second Order ◽  
Base Catalysis ◽  
Substitution Reactions ◽  
Third Order ◽  
Methoxy Derivative ◽  
First Order ◽  
General Base ◽  
Protic Solvents ◽  
Kinetics Of ◽  
Pyridinium Ions

The kinetics of nucleophilic substitution reactions of 1-(phenoxycarbonyl)pyridinium ions, prepared with the essentially non-nucleophilic/non-basic fluoroborate as the counterion, have been studied using up to 1.60 M methanol in acetonitrile as solvent and under solvolytic conditions in 2,2,2-trifluoroethan-1-ol (TFE) and its mixtures with water. Under the non- solvolytic conditions, the parent and three pyridine-ring-substituted derivatives were studied. Both second-order (first-order in methanol) and third-order (second-order in methanol) kinetic contributions were observed. In the solvolysis studies, since solvent ionizing power values were almost constant over the range of aqueous TFE studied, a Grunwald–Winstein equation treatment of the specific rates of solvolysis for the parent and the 4-methoxy derivative could be carried out in terms of variations in solvent nucleophilicity, and an appreciable sensitivity to changes in solvent nucleophilicity was found.

Metaontology

2018 ◽  
Author(s):  
Uriah Kriegel
Keyword(s):  
Second Order ◽  
Order Property ◽  
First Order ◽  
First Approximation

Brentano’s theory of judgment serves as a springboard for his conception of reality, indeed for his ontology. It does so, indirectly, by inspiring a very specific metaontology. To a first approximation, ontology is concerned with what exists, metaontology with what it means to say that something exists. So understood, metaontology has been dominated by three views: (i) existence as a substantive first-order property that some things have and some do not, (ii) existence as a formal first-order property that everything has, and (iii) existence as a second-order property of existents’ distinctive properties. Brentano offers a fourth and completely different approach to existence talk, however, one which falls naturally out of his theory of judgment. The purpose of this chapter is to present and motivate Brentano’s approach.

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