scholarly journals When Attended and Conscious Perception Deactivates Fronto-Parietal Regions

2016 ◽  
Author(s):  
Ausaf Ahmed Farooqui ◽  
Tom Manly
Keyword(s):  
Real Life ◽  
Perceptual Task ◽  
Conscious Perception ◽  
Perceptual Awareness ◽  
Top Down ◽  
Correct Rule ◽  
Goal Completion ◽  
Auditory Cue ◽  
Incoming Information ◽  
Widespread Availability

AbstractConscious and attended perception is commonly thought to elicit fronto-parietal activity. However, supportive evidence comes largely from studies which involve detecting a target and reporting its visibility. This approach confounds conscious perception with goal completion of either the perceptual task of detection or the metacognitive task of introspective reporting. In contrast, in real life such perceptions are a means of achieving goals and rarely a goal in themselves, and almost never involve explicit metacognitive reports. It therefore remains unclear if fronto-parietal activity is indeed a correlate of conscious perception or is the result of confounds related to goal completion. Here we show that conscious and attended perception when delinked from goals does not increase fronto-parietal activity, and when inconsequential for the goal may even deactivate these regions. In experiments 1 and 2 participants attended to a highly visible stream of letters to detect the occasional targets in their midst. The non-target letters, in spite of being visible and attended to, deactivated fronto-parietal regions. In experiment 3 we looked at the activity elicited by a loud auditory cue that had to be kept in memory for up to 9 s and used to select the correct rule for completing the goal. Even such a salient, attended and remembered event did not elicit prefrontal activity. Across these experiments conscious and attended perception only activated the relevant sensory regions while goal completion events activated fronto-parietal regions.Significance statementConsciousness and attended perception has been seen to correlate with fronto-parietal activity. This informs key theories of consciousness and attention, e.g. widespread availability of incoming information or its higher level representation causes perceptual awareness, or that top down attention during perception broadcasts incoming sensations into frontal and parietal regions. However such experiments unwittingly conflate attended and conscious perception with some form of goal completion, whereas such perception in our daily life mostly serves as a means of goal completion and not a goal in itself. Here we show that such perception when delinked from goal completion does not activate fronto-parietal regions, and may even deactivate these regions if the percept is inconsequential for goal completion.

Cactus: Top-Down GPU-Compute Benchmarking using Real-Life Applications

2021 ◽  
Author(s):  
Mahmood Naderan-Tahan ◽  
Lieven Eeckhout
Keyword(s):  
Real Life ◽  
Top Down

DisCoord: a serious game for co-creating knowledge for Disaster Risk Reduction

2021 ◽  
Author(s):  
Gina Delima ◽  
Liesbet Jacobs ◽  
Maarten Loopmans ◽  
Mary Ekyaligonza ◽  
Clovis Kabaseke ◽  
...  
Keyword(s):  
Risk Reduction ◽  
Public Space ◽  
Serious Games ◽  
Disaster Risk Reduction ◽  
Real Life ◽  
Disaster Risk ◽  
Serious Game ◽  
Public Pedagogy ◽  
Top Down ◽  
Creation Process

<p>Effective disaster risk reduction (DRR) presupposes awareness among key stakeholders on the causal factors that exacerbate disaster risks as well as a feeling of ownership over proposed DRR measures. Yet, the prevailing top-down communication of risk and the expert-centered knowledge have a limited impact in bringing significant positive change. Serious games respond to the need for a community-based DRR approach as they encourage a collective recognition of societal issues and co-learning at the different levels of the DRR governance system. However, there is still a gap in understanding how serious games facilitate co-creation of knowledge. In this article, we first introduce a serious game, called DisCoord, as a public pedagogy tool that bridges diverse views and sets of knowledge of DRR stakeholders separated by spatial and socio-cultural domains. Second, through a qualitative method of analysis of the 10 game sessions in Uganda, we examine the factors and processes that influence knowledge co-creation. The game actors – game designers, game facilitators and players – primarily steer and influence the co-creation process. These actors have diverse pre-game views, which are expressed through the game rules, arguments, game strategies, and game outcomes, and are confronted within the public space provided by the game. We find that crises experienced during the game, real-life based arguments provided by the players and own interpretations by the players are key factors in the co-creation process. This study leads us to conclude that games like DisCoord are useful as public pedagogy intervention as they bring different forms of knowledge together in a public space and facilitate co-learning. This paper also contends that countering a top-down approach of risk communication using a public pedagogy approach requires an openness towards the unpredictable, de-centered DRR, and plural co-learning outcomes.</p>

scholarly journals The Global Laboratory of Investment Law Reform Alternatives

AJIL Unbound ◽  
2018 ◽  
Vol 112 ◽  
pp. 237-243
Author(s):  
Wolfgang Alschner
Keyword(s):  
Real Life ◽  
Analytical Framework ◽  
The Other ◽  
Law Reform ◽  
Institutional Choice ◽  
Top Down ◽  
Policy Goal ◽  
Bottom Up ◽  
Investment Law ◽  
Institutional Choices

There are two ways of thinking about institutional choice in the context of multilateral investment law reform. One starts from abstract principles, asking what policy goal investment law is supposed to achieve and what institutional choice most effectively advances that goal. The other draws on practical experimentation, asking what institutional choices states are making and how these choices perform in real life. Sergio Puig and Gregory Shaffer present a compelling analytical framework for the former, top-down approach to investment law reform. In this essay, I will scrutinize their analysis and argue that the latter, bottom-up approach is more promising.

EXTRACTION OF HANDWRITTEN DATA FROM NOISY GRAY-LEVEL IMAGES USING A MULTISCALE APPROACH

1999 ◽  
Vol 13 (05) ◽  
pp. 665-684 ◽  
Author(s):  
MOHAMED CHERIET
Keyword(s):  
Spatial Scales ◽  
Real Life ◽  
Quality Data ◽  
Multiscale Approach ◽  
Gray Level ◽  
Top Down ◽  
Full Data ◽  
Wide Range ◽  
Over The Top ◽  
Gray Level Images

This paper presents a new methodology to extract visual data contained in noisy gray-level images such as mail envelopes. Since the intensity changes may occur over a large range of spatial scales in these and other like images, we adopt the multiscale approach to extract good quality data that might be used in further processing and recognition processes. We have already shown in a previous paper its effective use in full data extraction. In this paper, we will give an advanced formalism of this result, referred to as a top–down approach. Then, we will present a new and opposite approach, referred to as a bottom–up approach. The differences and characteristics of both approaches are highlighted. Experiments have been conducted on real life data from the data base provided by CEDAR at SUNY Buffalo, to assess the effectiveness of the proposed paradigm; this reveals its improved robustness and accuracy over the top–down approach; such a result might be useful for a wide range of applications in the field of image processing and enhancement.

scholarly journals Subjective visual perception: from local processing to emergent phenomena of brain activity

2014 ◽  
Vol 369 (1641) ◽  
pp. 20130534 ◽  
Author(s):  
Theofanis I. Panagiotaropoulos ◽  
Vishal Kapoor ◽  
Nikos K. Logothetis
Keyword(s):  
Visual Perception ◽  
Visual Stimulation ◽  
Brain Activity ◽  
Sensory Information ◽  
Brain Regions ◽  
Intrinsic Activity ◽  
Subjective Perception ◽  
Conscious Perception ◽  
Perceptual Awareness ◽  
Sensory Stimuli

The combination of electrophysiological recordings with ambiguous visual stimulation made possible the detection of neurons that represent the content of subjective visual perception and perceptual suppression in multiple cortical and subcortical brain regions. These neuronal populations, commonly referred to as the neural correlates of consciousness , are more likely to be found in the temporal and prefrontal cortices as well as the pulvinar, indicating that the content of perceptual awareness is represented with higher fidelity in higher-order association areas of the cortical and thalamic hierarchy, reflecting the outcome of competitive interactions between conflicting sensory information resolved in earlier stages. However, despite the significant insights into conscious perception gained through monitoring the activities of single neurons and small, local populations, the immense functional complexity of the brain arising from correlations in the activity of its constituent parts suggests that local, microscopic activity could only partially reveal the mechanisms involved in perceptual awareness. Rather, the dynamics of functional connectivity patterns on a mesoscopic and macroscopic level could be critical for conscious perception. Understanding these emergent spatio-temporal patterns could be informative not only for the stability of subjective perception but also for spontaneous perceptual transitions suggested to depend either on the dynamics of antagonistic ensembles or on global intrinsic activity fluctuations that may act upon explicit neural representations of sensory stimuli and induce perceptual reorganization. Here, we review the most recent results from local activity recordings and discuss the potential role of effective, correlated interactions during perceptual awareness.

scholarly journals Should a few null findings falsify prefrontal theories of conscious perception?

2017 ◽  
Author(s):  
Brian Odegaard ◽  
Robert T. Knight ◽  
Hakwan Lau
Keyword(s):  
Essential Role ◽  
Subjective Experience ◽  
Perceptual Content ◽  
Subjective Perception ◽  
Conscious Perception ◽  
Perceptual Awareness ◽  
Visual Tasks ◽  
Common Misconceptions ◽  
Limited Sensitivity

AbstractIs activity in prefrontal cortex (PFC) critical for conscious perception? Major theories of consciousness make distinct predictions about the role of PFC, providing an opportunity to arbitrate between these views empirically. Here we address three common misconceptions: i) PFC lesions do not affect subjective perception; ii) PFC activity does not reflect specific perceptual content; iii) PFC involvement in studies of perceptual awareness is solely driven by the need to make reports required by the experimental tasks, rather than subjective experience per se. These claims are incompatible with empirical findings, unless one focuses only on studies using methods with limited sensitivity. The literature highlights PFC’s essential role in enabling the subjective experience in perception, contra the objective capacity to perform visual tasks; conflating the two can also be a source of confusion.

scholarly journals Causal manipulation of feed-forward and recurrent processing differentially affects measures of consciousness

2020 ◽  
Vol 2020 (1) ◽  
Author(s):  
Christopher Allen ◽  
Tommaso Viola ◽  
Elizabeth Irvine ◽  
Jemma Sedgmond ◽  
Heidi Castle ◽  
...  
Keyword(s):  
Cognitive Processes ◽  
Neural Activity ◽  
Magnetic Stimulation ◽  
Conscious Perception ◽  
Top Down ◽  
Feed Forward ◽  
Cortical Dynamics ◽  
Recurrent Processing ◽  
Early Effects ◽  
Initial Processing

Abstract It has been theorized that cortical feed-forward and recurrent neural activity support unconscious and conscious cognitive processes, respectively. Here we causally tested this proposition by applying event-related transcranial magnetic stimulation (TMS) at early and late times relative to visual stimuli, together with a pulse designed to suppress conscious detection. Consistent with pre-registered hypotheses, early TMS affected residual, reportedly ‘unseen’ capacity. However, conscious perception also appeared critically dependent upon feed-forward processing to a greater extent than the later recurrent phase. Additional exploratory analyses suggested that these early effects dissociated from top-down criterion measures, which were most affected by later TMS. These findings are inconsistent with a simple dichotomy where feed-forward and recurrent processes correspond to unconscious and conscious mechanisms. Instead, different components of awareness may correspond to different phases of cortical dynamics in which initial processing is broadly perceptual whereas later recurrent processing might relate to decision to report.

scholarly journals Land Value Recapture in the US: The Case of San Francisco

2014 ◽  
Vol 11 ◽  
pp. 330-337 ◽  
Author(s):  
Nico Calavita
Keyword(s):  
World War Ii ◽  
International Finance ◽  
San Francisco ◽  
Real Life ◽  
Comprehensive Model ◽  
World War ◽  
Top Down ◽  
The Us ◽  
Market Driven ◽  
And Control

During the period immediately after World War II, planning in North America and Europe followed highly centralized, top-down, command-and-control approaches that were based on the rational-comprehensive model of planning, which implies an all-knowing, all-powerful government. Part and parcel of this approach was the government’s control of development land and its value. Beginning in the 1970s, as the precepts of an all-knowing, interventionist state clashed with the reality of uncontrollable global forces driven by multinationals and international finance, it became clear that planning had become a market-driven process, a “servant of the market,” and that inflexible, detailed plans would not work in most real-life situations. Consequently, such plans were either ignored or overridden

scholarly journals Neural and computational processes of accelerated perceptual awareness and decisions: A 7T fMRI Study

2021 ◽  
Author(s):  
Shivam Kalhan ◽  
Jessica McFadyen ◽  
Naotsugu Tsuchiya ◽  
Marta Garrido
Keyword(s):  
Visual Processing ◽  
Response Times ◽  
Computational Modelling ◽  
Occipital Lobe ◽  
Conscious Perception ◽  
Perceptual Awareness ◽  
Evidence Accumulation ◽  
Fearful Faces ◽  
Fmri Study ◽  
Neural Computations

Rapidly detecting salient information in our environments is critical for survival. Visual processing in subcortical areas like the pulvinar and amygdala have been shown to facilitate unconscious processing of salient stimuli. It is unknown, however, if and how these areas might interact with cortical networks to facilitate faster conscious perception of salient stimuli. Here we investigated these neural processes using 7T functional Magnetic Resonance Imaging (fMRI) in concert with computational modelling while participants (n = 32) engaged in a breaking continuous flash suppression paradigm (bCFS) in which fearful and neutral faces are initially suppressed from conscious perception but then eventually breakthrough into awareness. We found that participants reported faster breakthrough times for fearful faces compared to neutral faces. Drift-diffusion modelling suggested that perceptual evidence was accumulated at a faster rate for fearful faces compared to neutral faces. For both neutral and fearful faces, faster response times coincided with greater activity in the amygdala (specifically within its subregions, including superficial, basolateral and amygdalo-striatal transition area) and the insula. Faster rates of evidence accumulation coincided with greater activity in frontoparietal regions and the occipital lobe, as well as the amygdala. Overall, our findings suggest that hastened perceptual awareness of salient stimuli recruits the amygdala and, more specifically, is driven by accelerated evidence accumulation in fronto-parietal and visual areas. In sum, we have uncovered and mapped distinct neural computations that accelerate perceptual awareness of visually suppressed faces.

Sign in / Sign up

Export Citation Format

Share Document