scholarly journals The role of feature-based attention in visual serial dependence

2019 ◽  
Author(s):  
Matthias Fritsche ◽  
Floris P. de Lange
Keyword(s):  
Sensory Input ◽  
Internal Noise ◽  
Serial Dependence ◽  
Recent Past ◽  
Neural Representations ◽  
Selective Stabilization ◽  
The Face ◽  
Feature Based

AbstractPerceptual decisions about current sensory input are biased towards input of the recent past – a phenomenon termed serial dependence. Serial dependence may serve to stabilize neural representations in the face of external and internal noise. However, it is unclear under which circumstances previous input attracts subsequent perceptual decisions, and thus, whether serial dependence reflects a broad smoothing or selective stabilization operation. Here, we investigated whether focusing attention on particular features of the previous stimulus modulates serial dependence. We found an attractive bias in orientation estimations when previous and current stimuli had similar orientations, and a repulsive bias when they had dissimilar orientations. The attractive bias was markedly reduced when observers attended to the size, rather than the orientation, of the previous stimulus. Conversely, the repulsive bias for stimuli with large orientation differences was not modulated by feature-based attention. This suggests separate sources of these positive and negative perceptual biases.

scholarly journals The role of feature-based attention in visual serial dependence

2019 ◽  
Vol 19 (13) ◽  
pp. 21 ◽  
Author(s):  
Matthias Fritsche ◽  
Floris P. de Lange
Keyword(s):  
Serial Dependence ◽  
Feature Based

scholarly journals Separable pupillary signatures of perception and action during perceptual multistability

2021 ◽  
Author(s):  
Jan Brascamp ◽  
Gilles De Hollander ◽  
Michael D Wertheimer ◽  
Ashley N DePew ◽  
Tomas Knapen
Keyword(s):  
Pupil Size ◽  
Sensory Input ◽  
Perception And Action ◽  
Task Execution ◽  
Non Invasive ◽  
Cortical Responses ◽  
Multistable Perception ◽  
The Face ◽  
Perceptual Changes

The pupil provides a rich, non-invasive measure of the neural bases of perception and cognition. It can particularly inform about the role of arousal-linked neuromodulation, which alters both cortical processing and pupil size. But a multitude of factors influence pupil size, which complicates interpretation. We measured pupil signals accompanying changes in multistable perception, i.e. accompanying endogenously-generated perceptual changes in the face of inconclusive sensory input. Perceptual changes were marked by a complex pupil response that could be decomposed into two components: a dilation tied to task execution and plausibly reflecting arousal-linked noradrenaline, and an overlapping constriction tied to the perceptual transient and plausibly reflecting altered cortical responses. Constriction, but not dilation, amplitude depended on the timing of perceptual changes, possibly providing an index of neural adaptation. We conclude that pupil size reflects several dissociable processes during perceptual multistability, and that arousal-linked neuromodulation shapes action but not perception in these circumstances.

scholarly journals Serial dependence and representational momentum in single-trial perceptual decisions

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
D. Pascucci ◽  
G. Plomp
Keyword(s):  
Sensory Input ◽  
Moving Objects ◽  
Temporal Dynamics ◽  
Representational Momentum ◽  
Serial Dependence ◽  
Recent Past ◽  
Single Trial ◽  
Sensory Signals ◽  
Different Types ◽  
Environmental Events

AbstractThe human brain has evolved to predict and anticipate environmental events from their temporal dynamics. Predictions can bias perception toward the recent past, particularly when the environment contains no foreseeable changes, but can also push perception toward future states of sensory input, like when anticipating the trajectory of moving objects. Here, we show that perceptual decisions are simultaneously influenced by both past and future states of sensory signals. Using an orientation adjustment task, we demonstrate that single-trial errors are displaced toward previous features of behaviorally relevant stimuli and, at the same time, toward future states of dynamic sensory signals. These opposing tendencies, consistent with decisional serial dependence and representational momentum, involve different types of processing: serial dependence occurs beyond objecthood whereas representational momentum requires the representation of a single object with coherent dynamics in time and space. The coexistence of these two phenomena supports the independent binding of stimuli and decisions over time.

Questions on the role of biofilms for the adaptation of microorganisms to unfavorable environmental factors by the example of P. aeruginosa

2020 ◽  
Vol 99 (4) ◽  
pp. 379-383
Author(s):  
Vasily N. Afonyushkin ◽  
N. A. Donchenko ◽  
Ju. N. Kozlova ◽  
N. A. Davidova ◽  
V. Yu. Koptev ◽  
...  
Keyword(s):  
Antibiotic Resistance ◽  
Environmental Factors ◽  
Barrier Function ◽  
Infectious Agent ◽  
Antagonistic Activity ◽  
The Body ◽  
Main Function ◽  
Pathogenic Potential ◽  
The Face

Pseudomonas aeruginosa is a widely represented species of bacteria possessing of a pathogenic potential. This infectious agent is causing wound infections, fibrotic cystitis, fibrosing pneumonia, bacterial sepsis, etc. The microorganism is highly resistant to antiseptics, disinfectants, immune system responses of the body. The responses of a quorum sense of this kind of bacteria ensure the inclusion of many pathogenicity factors. The analysis of the scientific literature made it possible to formulate four questions concerning the role of biofilms for the adaptation of P. aeruginosa to adverse environmental factors: Is another person appears to be predominantly of a source an etiological agent or the source of P. aeruginosa infection in the environment? Does the formation of biofilms influence on the antibiotic resistance? How the antagonistic activity of microorganisms is realized in biofilm form? What is the main function of biofilms in the functioning of bacteria? A hypothesis has been put forward the effect of biofilms on the increase of antibiotic resistance of bacteria and, in particular, P. aeruginosa to be secondary in charcter. It is more likely a biofilmboth to fulfill the function of storing nutrients and provide topical competition in the face of food scarcity. In connection with the incompatibility of the molecular radii of most antibiotics and pores in biofilm, biofilm is doubtful to be capable of performing a barrier function for protecting against antibiotics. However, with respect to antibodies and immunocompetent cells, the barrier function is beyond doubt. The biofilm is more likely to fulfill the function of storing nutrients and providing topical competition in conditions of scarcity of food resources.

The Modern Aristotle: Michael Polanyi’s Search for Truth against Nihilism

2018 ◽  
Author(s):  
Ronald Hoinski ◽  
Ronald Polansky
Keyword(s):  
Philosophy Of Science ◽  
Modern Science ◽  
Michael Polanyi ◽  
Contemporary Philosophy ◽  
The Face ◽  
Human Desire ◽  
The Mind ◽  
Theoretical Science

David Hoinski and Ronald Polansky’s “The Modern Aristotle: Michael Polanyi’s Search for Truth against Nihilism” shows how the general tendencies of contemporary philosophy of science disclose a return to the Aristotelian emphasis on both the formation of dispositions to know and the role of the mind in theoretical science. Focusing on a comparison of Michael Polanyi and Aristotle, Hoinski and Polansky investigate to what degree Aristotelian thought retains its purchase on reality in the face of the changes wrought by modern science. Polanyi’s approach relies on several Aristotelian assumptions, including the naturalness of the human desire to know, the institutional and personal basis for the accumulation of knowledge, and the endorsement of realism against objectivism. Hoinski and Polansky emphasize the promise of Polanyi’s neo-Aristotelian framework, which argues that science is won through reflection on reality.

Expansion of borders in the Kurdistan region and local and regional positions

2019 ◽  
Vol 3 (11) ◽  
pp. 1
Author(s):  
Harith Qahtan Abdullah ◽  
Abbas Fadel Atwan
Keyword(s):  
Middle East ◽  
Central Government ◽  
Kurdistan Region ◽  
War On Terrorism ◽  
National State ◽  
The Face ◽  
In The Beginning

The borders of Kurdistan represent an important point in Kurdish thought. They represent the hope of establishing their national state. The circumstances of the war on terrorism in Iraq and Syria have led to the emergence of what is known as a "propaganda" and the formation of a global front in its struggle. And with the signs of the collapse of the Syrian state and the weakness of the Iraqi state in the face of the "dashing" in the beginning. These circumstances led to the emergence of the role of the Kurdistan region in the confrontation "ISIS" and maintain the administrative border in the three provinces of Kurdistan in addition to the province of Kirkuk. That the circumstances of the war on terrorism created new international conditions on the Middle East arena, which will generate many problems between the Kurdistan region and the central government of Baghdad, as well as other problems between the region, Syria, Turkey and Iran. The war on terrorism has made countries free to fight the opposition groups under the name Terrorism by their classification. The Turkish side is fighting the PKK within the borders of the Kurdistan region, and this war can develop in a post-"warlike" phase. The war in Syria is also contradictory to vision and not resolved to a specific side and Iran's position on developments is encouraging.

FAITH–BASED COMMUNITIES AND POLITICS IN DULLSTROOM-EMNOTWENI: LOCAL STORIES OF IDENTITY

2016 ◽  
Vol 1 (1) ◽  
pp. 45-57 ◽  
Author(s):  
Christina Landman
Keyword(s):  
Higher Education ◽  
Service Delivery ◽  
Special Focus ◽  
Traditional Role ◽  
Cultural Conflicts ◽  
Local Identities ◽  
Political Interests ◽  
Local Municipality ◽  
The Face

A majority of the black community of Dullstroom-Emnotweni in the Mpumalanga highveld in the east of South Africa trace their descent back to the southern Ndebele of the so-called ‘Mapoch Gronden’, who lost their land in the 1880s to become farm workers on their own land. A hundred years later, in 1980, descendants of the ‘Mapoggers’ settled in the newly built ‘township’ of Dullstroom, called Sakhelwe, finding jobs on the railways or as domestic workers. Oral interviews with the inhabitants of Sakhelwe – a name eventually abandoned in favour of Dullstroom- Emnotweni – testify to histories of transition from landowner to farmworker to unskilled labourer. The stories also highlight cultural conflicts between people of Ndebele, Pedi and Swazi descent and the influence of decades of subordination on local identities. Research projects conducted in this and the wider area of the eMakhazeni Local Municipality reveal the struggle to maintain religious, gender and youth identities in the face of competing political interests. Service delivery, higher education, space for women and the role of faith-based organisations in particular seem to be sites of contestation. Churches and their role in development and transformation, where they compete with political parties and state institutions, are the special focus of this study. They attempt to remain free from party politics, but are nevertheless co-opted into contra-culturing the lack of service delivery, poor standards of higher education and inadequate space for women, which are outside their traditional role of sustaining an oppressed community.

The Prophetic Voice of the Church in a Democratic South Africa – A Theological Reflection

2018 ◽  
Vol 15 (2) ◽  
Author(s):  
Lufuluvhi Maria Mudimeli
Keyword(s):  
South Africa ◽  
Economic Transformation ◽  
The State ◽  
Black Liberation ◽  
South Africans ◽  
Black Liberation Theology ◽  
Prophetic Voice ◽  
The Face ◽  
The Church

This article is a reflection on the role and contribution of the church in a democratic South Africa. The involvement of the church in the struggle against apartheid is revisited briefly. The church has played a pivotal and prominent role in bringing about democracy by being a prophetic voice that could not be silenced even in the face of death. It is in this time of democracy when real transformation is needed to take its course in a realistic way, where the presence of the church has probably been latent and where it has assumed an observer status. A look is taken at the dilemmas facing the church. The church should not be bound and taken captive by any form of loyalty to any political organisation at the expense of the poor and the voiceless. A need for cooperation and partnership between the church and the state is crucial at this time. This paper strives to address the role of the church as a prophetic voice in a democratic South Africa. Radical economic transformation, inequality, corruption, and moral decadence—all these challenges hold the potential to thwart our young democracy and its ideals. Black liberation theology concepts are employed to explore how the church can become prophetically relevant in democracy. Suggestions are made about how the church and the state can best form partnerships. In avoiding taking only a critical stance, the church could fulfil its mandate “in season and out of season” and continue to be a prophetic voice on behalf of ordinary South Africans.

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