A Model of Motion Transparency Processing with Local Center-Surround Interactions and Feedback

2011 ◽  
Vol 23 (11) ◽  
pp. 2868-2914 ◽  
Author(s):  
Florian Raudies ◽  
Ennio Mingolla ◽  
Heiko Neumann
Keyword(s):  
Discrimination Task ◽  
Spatial Location ◽  
Large Field ◽  
Local Center ◽  
Motion Patterns ◽  
Local Competition ◽  
Competition Mechanism ◽  
Multiple Peak ◽  
The World ◽  
Weak Peak

Motion transparency occurs when multiple coherent motions are perceived in one spatial location. Imagine, for instance, looking out of the window of a bus on a bright day, where the world outside the window is passing by and movements of passengers inside the bus are reflected in the window. The overlay of both motions at the window leads to motion transparency, which is challenging to process. Noisy and ambiguous motion signals can be reduced using a competition mechanism for all encoded motions in one spatial location. Such a competition, however, leads to the suppression of multiple peak responses that encode different motions, as only the strongest response tends to survive. As a solution, we suggest a local center-surround competition for population-encoded motion directions and speeds. Similar motions are supported, and dissimilar ones are separated, by representing them as multiple activations, which occurs in the case of motion transparency. Psychophysical findings, such as motion attraction and repulsion for motion transparency displays, can be explained by this local competition. Besides this local competition mechanism, we show that feedback signals improve the processing of motion transparency. A discrimination task for transparent versus opaque motion is simulated, where motion transparency is generated by superimposing large field motion patterns of either varying size or varying coherence of motion. The model’s perceptual thresholds with and without feedback are calculated. We demonstrate that initially weak peak responses can be enhanced and stabilized through modulatory feedback signals from higher stages of processing.

scholarly journals The movement of motion-defined contours can bias perceived position

2009 ◽  
Vol 5 (2) ◽  
pp. 270-273 ◽  
Author(s):  
Szonya Durant ◽  
Johannes M Zanker
Keyword(s):  
Visual Processing ◽  
Spatial Location ◽  
Motion Processing ◽  
Local Motion ◽  
Motion Direction ◽  
Motion Patterns ◽  
Object Properties ◽  
Accurate Position ◽  
Processing Steps ◽  
Over Time

Illusory position shifts induced by motion suggest that motion processing can interfere with perceived position. This may be because accurate position representation is lost during successive visual processing steps. We found that complex motion patterns, which can only be extracted at a global level by pooling and segmenting local motion signals and integrating over time, can influence perceived position. We used motion-defined Gabor patterns containing motion-defined boundaries, which themselves moved over time. This ‘motion-defined motion’ induced position biases of up to 0.5°, much larger than has been found with luminance-defined motion. The size of the shift correlated with how detectable the motion-defined motion direction was, suggesting that the amount of bias increased with the magnitude of this complex directional signal. However, positional shifts did occur even when participants were not aware of the direction of the motion-defined motion. The size of the perceptual position shift was greatly reduced when the position judgement was made relative to the location of a static luminance-defined square, but not eliminated. These results suggest that motion-induced position shifts are a result of general mechanisms matching dynamic object properties with spatial location.

scholarly journals PENGEMBANGAN MEDIA PENDIDIKAN UNTUK INOVASI PEMBELAJARAN DI PESANTREN

Edupedia ◽  
2020 ◽  
Vol 5 (1) ◽  
pp. 35-44
Author(s):  
Sukandi
Keyword(s):  
Learning Environments ◽  
Teaching And Learning ◽  
Field Trials ◽  
Learning Activities ◽  
Large Field ◽  
Small Field ◽  
Design Validation ◽  
Advantages And Disadvantages ◽  
The World ◽  
Enhance Student Learning

The increasingly dynamic development of information technology has implications for the world of education, especially learning activities. One of them by using media for helping the easy learning process that is very receive as benefit. Learning media can enhance student learning help to create joyful learning. But is not all learning media that can be applied in every learning environments, because learning media has advantages and disadvantages in several aspect. For the example is classical learning methods such as wetonan and bandongan become a characteristic teaching and learning activities in pesantren. Because of that, require a efforts to develop educational media suitably with the learning and the needs of students. Learning media development procedures iclude are potential and problems, data collection, product design, design validation, revision, small-field trials, revision, large-field trials, revision, massive production.

scholarly journals A Sparse Unreliable Distributed Code Underlies the Limits of Behavioral Discrimination

2018 ◽  
Author(s):  
Balaji Sriram ◽  
Alberto Cruz-Martin ◽  
Lillian Li ◽  
Pamela Reinagel ◽  
Anirvan Ghosh
Keyword(s):  
Visual Cortex ◽  
Visual System ◽  
Single Unit ◽  
Discrimination Task ◽  
Orientation Discrimination ◽  
Behavioral Performance ◽  
High Contrast ◽  
The World ◽  
Mouse Visual Cortex ◽  
Linear Decoding

ABSTRACTThe cortical code that underlies perception must enable subjects to perceive the world at timescales relevant for behavior. We find that mice can integrate visual stimuli very quickly (<100 ms) to reach plateau performance in an orientation discrimination task. To define features of cortical activity that underlie performance at these timescales, we measured single unit responses in the mouse visual cortex at timescales relevant to this task. In contrast to high contrast stimuli of longer duration, which elicit reliable activity in individual neurons, stimuli at the threshold of perception elicit extremely sparse and unreliable responses in V1 such that the activity of individual neurons do not reliably report orientation. Integrating information across neurons, however, quickly improves performance. Using a linear decoding model, we estimate that integrating information over 50-100 neurons is sufficient to account for behavioral performance. Thus, at the limits of perception the visual system is able to integrate information across a relatively small number of highly unreliable single units to generate reliable behavior.

scholarly journals Advances in the study of signed languages within a cognitive perspective

2020 ◽  
Vol 23 ◽  
pp. 29-56
Author(s):  
Rocío Martínez ◽  
Sara Siyavoshi ◽  
Sherman Wilcox
Keyword(s):  
Cognitive Model ◽  
Spatial Location ◽  
Epistemic Modality ◽  
Cognitive Grammar ◽  
Signed Languages ◽  
Signed Language ◽  
Symbolic Structure ◽  
Pointing Device ◽  
The World ◽  
Using Data

In this paper we describe a cognitive grammar approach to the study of signed language grammar. Using data from different signed languages, we explore three broad topics. First, we examine pointing, Place, and placing. We analyze pointing as a construction consisting of a pointing device, a symbolic structure which directs the interlocutor’s conceptual attention, and a Place, a symbolic structure consisting of a spatial location and a meaning, the focus of attention. Placing is a construction in which non-body anchored signs are placed at a location in space, thereby creating or recruiting a Place structure which can be used in subsequent discourse. We examine how these structures work in nominal grounding and in extended discourse. Second, we examine a cognitive grammar approach to grammatical modality. Our analysis is based on the cognitive model called the control cycle, which posits two types of control: effective, which describes our striving to influence what happens in the world, and epistemic, which concerns how we make sense of the world. We explore how effective and epistemic modality are expressed in facial displays, focusing on the brow furrow and a display with down-turned corners of the mouth we call the horseshoe mouth. Finally, we offer a brief account of a cognitive grammar approach to the relation between sign and gesture.

ACTUAL PROBLEMS OF COMPLEX SPATIAL RESEARCH IN RUSSIA, TAKING INTO ACCOUNT THE WORLD EXPERIENCE

2021 ◽  
Vol 1 (3) ◽  
pp. 4-11
Author(s):  
M. I. SEREDINA ◽  
◽  
I. L. CHERKASOV ◽  
Keyword(s):  
Retrospective Analysis ◽  
Russian Federation ◽  
Spatial Location ◽  
Russian Empire ◽  
Spatial Studies ◽  
The World ◽  
The Russian Federation ◽  
The Russian Empire ◽  
Different Levels ◽  
Theoretical Developments

The authors considered the background and conducted a brief retrospective analysis of complex spatial studies in the Russian Empire, in Soviet and modern Russia. The use of world theoretical developments in justifying the spatial location of economic objects in the Russian Federation is studied. Conclusions are drawn about the weak level of regional forecasting, programming and planning at different levels.

Off on the Wrong Foot: Local Features in Biological Motion

Perception ◽  
10.1068/p6140 ◽  
2009 ◽  
Vol 38 (4) ◽  
pp. 522-532 ◽  
Author(s):  
Daniel R Saunders ◽  
Julia Suchan ◽  
Nikolaus F Troje
Keyword(s):  
Motion Perception ◽  
Discrimination Task ◽  
Biological Motion ◽  
Large Body ◽  
Detection Task ◽  
Observer Performance ◽  
Local Motion ◽  
Motion Patterns ◽  
Direction Discrimination ◽  
Biological Motion Perception

Biological-motion perception consists of a number of different phenomena. They include global mechanisms that support the retrieval of the coherent shape of a walker, but also mechanisms which derive information from the local motion of its parts about facing direction and animacy, independent of the particular shape of the display. A large body of the literature on biological-motion perception is based on a synthetic stimulus generated by an algorithm published by James Cutting in 1978 ( Perception7 393–405). Here we show that this particular stimulus lacks a visual invariant inherent to the local motion of the feet of a natural walker, which in more realistic motion patterns indicates the facing direction of a walker independent of its shape. Comparing Cutting's walker to a walker derived from motion-captured data of real human walkers, we find no difference between the two displays in a detection task designed such that observers had to rely on global shape. In a direction discrimination task, however, in which only local motion was accessible to the observer, performance on Cutting's walker was at chance, while direction could still be retrieved from the stimuli derived from the real walker.

The Father, the Son, and John on Location in the Farewell Discourse

2020 ◽  
Vol 7 (1) ◽  
pp. 7-29
Author(s):  
Harry O. Maier
Keyword(s):  
Religious Identity ◽  
Social Geography ◽  
Spatial Location ◽  
Dynamic Relationship ◽  
Farewell Discourse ◽  
The World ◽  
John's Gospel ◽  
Relationship Of ◽  
Spatial Identity ◽  
Edward Soja

AbstractUsing the tools of social geography, specifically those developed by Edward Soja, Henri Lefebvre, and Oliver Sacks, this article explores the Gospel of John’s spatial reference to place as it appears in Jesus’ Farewell Discourse (John 14–17) and the ways it uses narrative to create places for the practices and conceiving of religious identity. Although application of spatial study to John’s gospel is relatively rare in Johannine studies, it promises a great deal of insight, especially because John’s gospel is filled with numerous references to place and a rich variety of prepositional phrases. Through narrative, John offers a spatial temporalization (following Soja, a ‘thirdspace’) for audiences to inhabit and interpret the world around them. John’s Father-Son-Paraclete language of unity (which the Christian tradition has interpreted metaphysically and soteriologically without reference to time and space) creates a place for Johannine discipleship in which listeners reenact the dynamic relationship of its three divine actors. John establishes a particular mode of spatial identity by presenting Father, Son, and Paraclete, together with the narrative’s antagonists and protagonists in particular spaces with a set of behaviors associated with each location. The Johannine reference to Jesus going to prepare a place for his disciples after his death (John 13:36), and the reference to a mansion with many room (John 14:2–4) is traditionally interpreted as a reference to the afterlife or a heavenly domain. Scholars have debated whether this represents a futurist or a realized eschatological teaching. A spatial application offers new insights by viewing it from a social geographical perspective as a spatial location “in the world,” lived out locationally “in” the Paraclete, in rejection by the “world.” Metaphysical unity language refers to a narrative of rejection and suffering, which reveals the identity of Johannine believers “in but not of the world.” In this regard, John reflects sapiential themes found in the Hebrew Bible and the intertestamental period that tell of wisdom dwelling on earth and also being rejected.

scholarly journals Modeling Binocular and Motion Transparency Processing by Local Center-Surround Interactions

2012 ◽  
pp. 121-153
Author(s):  
Florian Raudies ◽  
Heiko Neumann
Keyword(s):  
Spatial Location ◽  
Cell Populations ◽  
Local Center ◽  
Multiple Features ◽  
Temporal Area ◽  
Model Simulations ◽  
Initial Correlations ◽  
Area V2 ◽  
Different Depths ◽  
Stereo Processing

Binocular transparency is perceived if two surfaces are seen in the same spatial location, but at different depths. Similarly, motion transparency occurs if two surfaces move differently over the same spatial location. Most models of motion or stereo processing incorporate uniqueness assumptions to resolve ambiguities of disparity or motion estimates and, thus, can not represent multiple features at the same spatial location. Unlike these previous models, the authors of this chapter suggest a model with local center-surround interaction that operates upon analogs of cell populations in velocity or disparity domain of the ventral second visual area (V2) and dorsal medial middle temporal area (MT) in primates, respectively. These modeled cell populations can encode motion and binocular transparency. Model simulations demonstrate the successful processing of scenes with opaque and transparent materials, not previously reported. Results suggest that motion and stereo processing both employ local center-surround interactions to resolve noisy and ambiguous disparity or motion input from initial correlations.

Parallel Import in India

2017 ◽  
pp. 75-88
Author(s):  
Dinesh Kumar ◽  
Gurjinder Singh
Keyword(s):  
Intellectual Property ◽  
Property Right ◽  
Intellectual Property Right ◽  
Parallel Imports ◽  
Local Competition ◽  
Parallel Import ◽  
Black And White ◽  
Contemporary View ◽  
The World ◽  
International Issues

People often say that the world is not only “Black and White” but there are many other shades which pose difficult question. Parallel import, which is also known as “Grey area” is one of them. Parallel imports are goods produced genuinely under protection of a trademark, patent, or copyright, placed in one market, and then imported into another market without the approval of the Intellectual Property Right holder. Through this chapter, the Author(s) have tried to give an insight on parallel imports by discussing all possible national and international issues related to it. Some principal concepts like exhaustion, regional and global have acquired considerable space in the chapter. A brief contemporary view on parallel import has also been taken by the author(s). The contradictory views; one which favours the Parallel imports by endorsing that it enhances the local competition; and another which condemns parallel imports are covered in the later part of the chapter.

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