scholarly journals Control of gaze in natural environments: effects of rewards and costs, uncertainty and memory in target selection

2018 ◽  
Vol 8 (4) ◽  
pp. 20180009 ◽  
Author(s):  
Mary M. Hayhoe ◽  
Jonathan Samir Matthis

The development of better eye and body tracking systems, and more flexible virtual environments have allowed more systematic exploration of natural vision and contributed a number of insights. In natural visually guided behaviour, humans make continuous sequences of sensory-motor decisions to satisfy current goals, and the role of vision is to provide the relevant information in order to achieve those goals. This paper reviews the factors that control gaze in natural visually guided actions such as locomotion, including the rewards and costs associated with the immediate behavioural goals, uncertainty about the state of the world and prior knowledge of the environment. These general features of human gaze control may inform the development of artificial systems.

Author(s):  
James Kim

The purpose of this study was to examine factors that influence how people look at objects they will have to act upon while watching others interact with them first. We investigated whether including different types of task-relevant information into an observational learning task would result in participants adapting their gaze towards an object with more task-relevant information. The participant watched an actor simultaneously lift and replace two objects with two hands then was cued to lift one of the two objects. The objects had the potential to change weight between each trial. In our cue condition, participants were cued to lift one of the objects every single time. In our object condition, the participants were cued equally to act on both objects; however, the weights of only one of the objects would have the potential to change. The hypothesis in the cue condition was that the participant would look significantly more at the object being cued. The hypothesis for the object condition was that the participant would look significantly more (i.e. adapt their gaze) at the object changing weight. The rationale behind this is that participants will learn to allocate their gaze significantly more towards that object so they can gain information about its properties (i.e. weight change). Pending results will indicate whether or not this occurred, and has implications for understanding eye movement sequences in visually guided behaviour tasks. The outcome of this study also has implications for the mechanisms of eye gaze with respect to social learning tasks. 


2019 ◽  
Author(s):  
Alexia Bourgeois ◽  
Carole Guedj ◽  
Emmanuel Carrera ◽  
Patrik Vuilleumier

Selective attention is a fundamental cognitive function that guides behavior by selecting and prioritizing salient or relevant sensory information of our environment. Despite early evidence and theoretical proposal pointing to an implication of thalamic control in attention, most studies in the past two decades focused on cortical substrates, largely ignoring the contribution of subcortical regions as well as cortico-subcortical interactions. Here, we suggest a key role of the pulvinar in the selection of salient and relevant information via its involvement in priority maps computation. Prioritization may be achieved through a pulvinar- mediated generation of alpha oscillations, which may then modulate neuronal gain in thalamo-cortical circuits. Such mechanism might orchestrate the synchrony of cortico-cortical interaction, by rendering neural communication more effective, precise and selective. We propose that this theoretical framework will support a timely shift from the prevailing cortico- centric view of cognition to a more integrative perspective of thalamic contributions to attention and executive control processes.


2019 ◽  
Vol 15 (3) ◽  
pp. 156-158
Author(s):  
Aditi Priyamvara ◽  
Amit K. Dey ◽  
Antara Bagchi ◽  
Raveena Kelkar ◽  
Rajaram Sharma

Background: It is known that hormonal imbalances during pregnancy make women more susceptible to dental problems. High levels of progesterone and estrogen during pregnancy, lead to an increased inflammatory response to dental plaque thus causing predisposing to gum diseases such as gingivitis. If untreated, gingivitis leads to chronic periodontitis which may manifest systemically in form of cardiovascular, endocrine or even respiratory disorders. Also, hyperacidity in the oral cavity due to gastric reflux and vomiting leads to decreased pH thus damaging the tooth enamel making the oral cavity more prone to tooth decay and tooth loss. Studies also show that periodontal disease can also lead to adverse pregnancy outcomes such as pre-term and low birth weight babies. Objectives: We sought to understand the role of oral health in pregnancy. Methods: We identified major articles of interest in the field of oral health in pregnancy and drafted a mini-symposium based on relevant information. Conclusion: Regular dental visits and cognizant efforts to sustain a healthy oral environment can help women in the prevention and treatment of dental issues during pregnancy. The paper highlights the common oral manifestations during pregnancy and their local and systemic impact on the body during pregnancy. Furthermore, it also emphasizes the importance of good oral health practices to counteract the oral complications and the significance of oral health awareness in pregnant women.


2020 ◽  
Vol 22 (1) ◽  
pp. 92-97
Author(s):  
KONSTANTIN A. KORSIK ◽  
◽  
ANASTASIYA A. PARFENCHIKOVA ◽  

The article is devoted to the review of current changes in the legislation on notaries related to the development of electronic civil circulation, analysis of existing digital risks and assessment of the role of notaries in combating them. In modern economic realities, a significant expansion of the sphere of competence of the notary is carried out by introducing completely new notarial actions into the scope of the notary’s terms of reference. At the same time, the notary does not just follow the general ‘digital’ trend, but independently makes significant efforts to effectively perform the tasks of the social sphere regulator assigned to it by the state. The creation of the Unified Notary Information System as part of the formation of the technological infrastructure to ensure the security and stability of legal relations in the context of electronic civil circulation takes to a new level the quality of notarial services and the security of legally relevant information. The role of notaries significantly increases in conditions when the use of digital technologies in the economy, public administration, social sphere becomes one of the main vectors of world development, and society and the state inevitably face the flip side of this process – digital risks that jeopardize the safety of participants in civil turnover and their property. In 2020, as part of the implementation of the national program ‘Digital Economy’, it is planned to introduce a number of innovations that will create the basis for a stable and secure ‘digital’ turnover.


2021 ◽  
Vol 11 (5) ◽  
pp. 57
Author(s):  
Valentina Cesari ◽  
Benedetta Galgani ◽  
Angelo Gemignani ◽  
Danilo Menicucci

Online-learning is a feasible alternative to in-person attendance during COVID-19 pandemic. In this period, information technologies have allowed sharing experiences, but have also highlighted some limitations compared to traditional learning. Learning is strongly supported by some qualities of consciousness such as flow (intended as the optimal state of absorption and engagement activity) and sense of presence (feeling of exerting control, interacting with and getting immersed into real/virtual environments), behavioral, emotional, and cognitive engagement, together with the need for social interaction. During online learning, feelings of disconnection, social isolation, distractions, boredom, and lack of control exert a detrimental effect on the ability to reach the state of flow, the feeling of presence, the feeling of social involvement. Since online environments could prevent the rising of these learning–supporting variables, this article aims at describing the role of flow, presence, engagement, and social interactions during online sessions and at characterizing multisensory stimulations as a driver to cope with these issues. We argue that the use of augmented, mixed, or virtual reality can support the above-mentioned domains, and thus counteract the detrimental effects of physical distance. Such support could be further increased by enhancing multisensory stimulation modalities within augmented and virtual environments.


Sensors ◽  
2021 ◽  
Vol 21 (10) ◽  
pp. 3327
Author(s):  
Vicente Román ◽  
Luis Payá ◽  
Adrián Peidró ◽  
Mónica Ballesta ◽  
Oscar Reinoso

Over the last few years, mobile robotics has experienced a great development thanks to the wide variety of problems that can be solved with this technology. An autonomous mobile robot must be able to operate in a priori unknown environments, planning its trajectory and navigating to the required target points. With this aim, it is crucial solving the mapping and localization problems with accuracy and acceptable computational cost. The use of omnidirectional vision systems has emerged as a robust choice thanks to the big quantity of information they can extract from the environment. The images must be processed to obtain relevant information that permits solving robustly the mapping and localization problems. The classical frameworks to address this problem are based on the extraction, description and tracking of local features or landmarks. However, more recently, a new family of methods has emerged as a robust alternative in mobile robotics. It consists of describing each image as a whole, what leads to conceptually simpler algorithms. While methods based on local features have been extensively studied and compared in the literature, those based on global appearance still merit a deep study to uncover their performance. In this work, a comparative evaluation of six global-appearance description techniques in localization tasks is carried out, both in terms of accuracy and computational cost. Some sets of images captured in a real environment are used with this aim, including some typical phenomena such as changes in lighting conditions, visual aliasing, partial occlusions and noise.


Diagnostics ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 552
Author(s):  
Salam Awenat ◽  
Arnoldo Piccardo ◽  
Patricia Carvoeiras ◽  
Giovanni Signore ◽  
Luca Giovanella ◽  
...  

Background: The use of prostate-specific membrane antigen (PSMA)-targeted agents for staging prostate cancer (PCa) patients using positron emission tomography/computed tomography (PET/CT) is increasing worldwide. We performed a systematic review on the role of 18F-PSMA-1007 PET/CT in PCa staging to provide evidence-based data in this setting. Methods: A comprehensive computer literature search of PubMed/MEDLINE and Cochrane Library databases for studies using 18F-PSMA-1007 PET/CT in PCa staging was performed until 31 December 2020. Eligible articles were selected and relevant information was extracted from the original articles by two authors independently. Results: Eight articles (369 patients) evaluating the role of 18F-PSMA-1007 PET/CT in PCa staging were selected. These studies were quite heterogeneous, but, overall, they demonstrated a good diagnostic accuracy of 18F-PSMA-1007 PET/CT in detecting PCa lesions at staging. Overall, higher primary PCa aggressiveness was associated with higher 18F-PSMA-1007 uptake. When compared with other radiological and scintigraphic imaging methods, 18F-PSMA-1007 PET/CT had superior sensitivity in detecting metastatic disease and the highest inter-reader agreement. 18F-PSMA-1007 PET/CT showed similar results in terms of diagnostic accuracy for PCa staging compared with PET/CT with other PSMA-targeted tracers. Dual imaging with multi-parametric magnetic resonance imaging and 18F-PSMA-1007 PET/CT may improve staging of primary PCa. Notably, 18F-PSMA-1007-PET/CT may detect metastatic disease in a significant number of patients with negative standard imaging. Conclusions: 18F-PSMA-1007 PET/CT demonstrated a good accuracy in PCa staging, with similar results compared with other PSMA-targeted radiopharmaceuticals. This method could substitute bone scintigraphy and conventional abdominal imaging for PCa staging. Prospective multicentric studies are needed to confirm these findings.


2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Martin Giesel ◽  
Anna Nowakowska ◽  
Julie M. Harris ◽  
Constanze Hesse

AbstractWhen we use virtual and augmented reality (VR/AR) environments to investigate behaviour or train motor skills, we expect that the insights or skills acquired in VR/AR transfer to real-world settings. Motor behaviour is strongly influenced by perceptual uncertainty and the expected consequences of actions. VR/AR differ in both of these aspects from natural environments. Perceptual information in VR/AR is less reliable than in natural environments, and the knowledge of acting in a virtual environment might modulate our expectations of action consequences. Using mirror reflections to create a virtual environment free of perceptual artefacts, we show that hand movements in an obstacle avoidance task systematically differed between real and virtual obstacles and that these behavioural differences occurred independent of the quality of the available perceptual information. This suggests that even when perceptual correspondence between natural and virtual environments is achieved, action correspondence does not necessarily follow due to the disparity in the expected consequences of actions in the two environments.


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