scholarly journals Predictive Representations in Hippocampal and Prefrontal Hierarchies

2019 ◽  
Author(s):  
Iva K. Brunec ◽  
Ida Momennejad

AbstractAs we navigate the world, we use learned representations of relational structures to explore and reach goals. Studies of how relational knowledge enables inference and planning are typically conducted in controlled small-scale settings. It remains unclear, however, how people use stored knowledge in continuously unfolding navigation, e.g., walking long distances in a city. We hypothesized that predictive representations, organized at multiple scales along posterior-anterior prefrontal and hippocampal hierarchies, guide naturalistic navigation. We conducted model-based representational similarity analyses of neuroimaging data measured during navigation of realistically long paths in virtual reality. We tested the pattern similarity of each point–along each path–to a weighted sum of its successor points within different predictive horizons. We found that anterior PFC showed the largest predictive horizons, posterior hippocampus the smallest, with the anterior hippocampus and orbitofrontal regions in between. Our findings offer novel insights into how cognitive maps support hierarchical planning at multiple scales.

2021 ◽  
pp. 1-16
Author(s):  
Scott McKean ◽  
Simon Poirier ◽  
Henry Galvis-Portilla ◽  
Marco Venieri ◽  
Jeffrey A. Priest ◽  
...  

Summary The Duvernay Formation is an unconventional reservoir characterized by induced seismicity and fluid migration, with natural fractures likely contributing to both cases. An alpine outcrop of the Perdrix and Flume formations, correlative with the subsurface Duvernay and Waterways formations, was investigated to characterize natural fracture networks. A semiautomated image-segmentation and fracture analysis was applied to orthomosaics generated from a photogrammetric survey to assess small- and large-scale fracture intensity and rock mass heterogeneity. The study also included manual scanlines, fracture windows, and Schmidt hammer measurements. The Perdrix section transitions from brittle fractures to en echelon fractures and shear-damage zones. Multiple scales of fractures were observed, including unconfined, bedbound fractures, and fold-relatedbed-parallel partings (BPPs). Variograms indicate a significant nugget effect along with fracture anisotropy. Schmidt hammer results lack correlation with fracture intensity. The Flume pavements exhibit a regionally extensive perpendicular joint set, tectonically driven fracturing, and multiple fault-damage zones with subvertical fractures dominating. Similar to the Perdrix, variograms show a significant nugget effect, highlighting fracture anisotropy. The results from this study suggest that small-scale fractures are inherently stochastic and that fractures observed at core scale should not be extrapolated to represent large-scale fracture systems; instead, the effects of small-scale fractures are best represented using an effective continuum approach. In contrast, large-scale fractures are more predictable according to structural setting and should be characterized robustly using geological principles. This study is especially applicable for operators and regulators in the Duvernay and similar formations where unconventional reservoir units abut carbonate formations.


2021 ◽  
Vol 73 (1) ◽  
Author(s):  
H. Clark Barrett

Psychological research in small-scale societies is crucial for what it stands to tell us about human psychological diversity. However, people in these communities, typically Indigenous communities in the global South, have been underrepresented and sometimes misrepresented in psychological research. Here I discuss the promises and pitfalls of psychological research in these communities, reviewing why they have been of interest to social scientists and how cross-cultural comparisons have been used to test psychological hypotheses. I consider factors that may be undertheorized in our research, such as political and economic marginalization, and how these might influence our data and conclusions. I argue that more just and accurate representation of people from small-scale communities around the world will provide us with a fuller picture of human psychological similarity and diversity, and it will help us to better understand how this diversity is shaped by historical and social processes. Expected final online publication date for the Annual Review of Psychology, Volume 73 is January 2022. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.


2019 ◽  
Vol 4 (3) ◽  
pp. 194-207
Author(s):  
PIET GELEYNS

The Hoge Kempen rural industrial transition landscape: a layered landscape of Outstanding Universal Value? Up until the beginning of the 20th century, the eastern part of the Belgian province of Limburg was a sparsely populated and not very productive part of the country. The dominating heathland was maintained with sheep, which were an essential part of a small-scale extensive farming system. This all changed when coal was discovered in 1901. Seven large coalmines were established in a few decades, each one employing thousands of coal-miners. This also meant that entire new garden cities were built, to house the coal-miners and their families. The confrontation between the small-scale traditional land-use and the new large-scale industrial developments defines the landscape up to today. The scale and the force of the turnover are considered unprecedented for Western Europe, which is why it is being presented by Belgium for inclusion in the World Heritage List.


2017 ◽  
Vol 2 (2) ◽  
pp. 155-167
Author(s):  
Deb Cleland

Charting the course: The world of alternative livelihood research brings a heavy history of paternalistic colonial intervention and moralising. In particular, subsistence fishers in South East Asia are cyclical attractors of project funding to help them exit poverty and not ‘further degrade the marine ecosystem’ (Cinner et al. 2011), through leaving their boats behind and embarking on non-oceanic careers. What happens, then, when we turn an autoethnographic eye on the livelihood of the alternative livelihood researcher? What lexicons of lack and luck may we borrow from the fishers in order to ‘render articulate and more systematic those feelings of dissatisfaction’ (Young 2002) of an academic’s life’s work and our work-life? What might we learn from comparing small-scale fishers to small-scale scholars about how to successfully ‘navigate’ the casualised waters of the modern university? Does this unlikely course bring any ideas of ‘possibilities glimmering’ (Young 2002) for ‘exiting’ poverty in Academia?


2021 ◽  
Author(s):  
Ayesha Musa ◽  
Safia Khan ◽  
Minahil Mujahid ◽  
Mohamady

Memories are not formed in isolation. They are associated and organized into relational knowledge structures that allow coherent thought. Failure to express such coherent thought is a key hallmark of Schizophrenia. Here we explore the hypothesis that thought disorder arises from disorganized Hippocampal cognitive maps. In doing so, we combine insights from two key lines of investigation, one concerning the neural signatures of cognitive mapping, and another that seeks to understand lower-level cellular mechanisms of cognition within a dynamical systems framework. Specifically, we propose that multiple distinct pathological pathways converge on the shallowing of Hippocampal attractors, giving rise to disorganized Hippocampal cognitive maps and driving thought disorder. We discuss the available evidence at the computational, behavioural, network and cellular levels. We also outline testable predictions from this framework including how it could unify major chemical and psychological theories of schizophrenia and how it can provide a rationale for understanding the aetiology and treatment of the disease.


2021 ◽  
pp. 1-31
Author(s):  
Filippo Osella

Abstract Drawing on ethnographic data collected in China, the United Arab Emirates (UAE), and India, this article explores the life-world and practices of small-scale Indian export agents based in Yiwu, China, the world centre for the export of small commodities. It shows that in a market overdetermined by fast-moving goods, short-term gains, and low margins, export agents have to steer their way between acting with extreme caution or taking risks with their clients and suppliers. These apparently contradictory dispositions or orientations are negotiated by the judicious exercise of mistrust and suspicion. The article suggests not only that mistrust is valued and cultivated as an indispensable practical resource for success in Yiwu's export trade, but that contingent relations of trust between market players emerge at the interstices of a generalized mutual mistrust, via the mobilization of practices of hospitality, commensality, and masculine conviviality. Indeed, feelings of amity and mutuality elicited by the performance of modalities of social intimacy become the affective terrain upon which divergent economic interests might be reconciled and taken forward. That is, mistrust might not lead to generalized distrust, instead a situational or contingent trust might actually emerge through the judicious exercise of mistrust.


Mathematics ◽  
2021 ◽  
Vol 9 (21) ◽  
pp. 2815
Author(s):  
Shih-Hung Yang ◽  
Yao-Mao Cheng ◽  
Jyun-We Huang ◽  
Yon-Ping Chen

Automatic fingerspelling recognition tackles the communication barrier between deaf and hearing individuals. However, the accuracy of fingerspelling recognition is reduced by high intra-class variability and low inter-class variability. In the existing methods, regular convolutional kernels, which have limited receptive fields (RFs) and often cannot detect subtle discriminative details, are applied to learn features. In this study, we propose a receptive field-aware network with finger attention (RFaNet) that highlights the finger regions and builds inter-finger relations. To highlight the discriminative details of these fingers, RFaNet reweights the low-level features of the hand depth image with those of the non-forearm image and improves finger localization, even when the wrist is occluded. RFaNet captures neighboring and inter-region dependencies between fingers in high-level features. An atrous convolution procedure enlarges the RFs at multiple scales and a non-local operation computes the interactions between multi-scale feature maps, thereby facilitating the building of inter-finger relations. Thus, the representation of a sign is invariant to viewpoint changes, which are primarily responsible for intra-class variability. On an American Sign Language fingerspelling dataset, RFaNet achieved 1.77% higher classification accuracy than state-of-the-art methods. RFaNet achieved effective transfer learning when the number of labeled depth images was insufficient. The fingerspelling representation of a depth image can be effectively transferred from large- to small-scale datasets via highlighting the finger regions and building inter-finger relations, thereby reducing the requirement for expensive fingerspelling annotations.


Author(s):  
Olga Markova ◽  
Valentina Maslennikova

The largest countries of the world are inevitably involved in various global processes, both natural and socio-economic. These countries have common features and characteristic differences in the state of their territorial resources; the study of these characteristics is of interest for the global prospects of sustainable development. A large territory provides a variety of natural conditions and resources for the country; however, not in all countries it is possible to effectively use them in the economy throughout the all country. An analysis of their territorial resources was carried out for the six largest countries of the world according to the following parameters: area, efficiency, environmental load on the territory of the country, number, density, forecast of population growth or decline for 2050, main agricultural land (arable land, pastures, the provision of the population, degradation and pollution of the soils), forest resources (including security per capita, share in the area of countries), fresh water resources (including per capita provision and availability), greenhouse gas emissions, including per capita, the proportion of mammals endangered, proportion of areas of preserved ecosystems. The data obtained was displayed on the maps; a common legend is built for them in tabular form. A number of other parameters of the state of territorial resources and the environment were also studied. In the process of research, the most important cities of these countries were also studied and diagrams showing their similarities and differences in a number of indicators were constructed: area, population and population density, time of foundation, climatic and landscape parameters, the presence of UNESCO World Heritage Sites, high-rise construction parameters. The developed methodology is effective for assessing a variety of data on territorial resources that can be used to build models of sustainable development of the largest countries and regions of the Earth.


2020 ◽  
Vol 47 (3) ◽  
pp. 159-173
Author(s):  
Paola Migliorini ◽  
Paolo Bàrberi ◽  
Stéphane Bellon ◽  
Tommaso Gaifami ◽  
Vassilis D. Gkisakis ◽  
...  

Seven potential controversial topics in agroecology are presented and discussed from a European perspective comparing the position of Agroecology Europe (AEEU) obtained from an iterative, participatory approach with members and compared with published literature, including views from other parts of the world. The seven controversial topics as follows: i) use of agrochemicals; ii) small-scale and peasant farming versus larger farms; iii) technological innovations in agriculture and precision farming; iv) biotechnology and genetic engineering in agriculture; v) local and short food circuits; vi) social justice; vii) gender perspective. The analysis shows that there are diverse points of view related to geographical area and sociopolitical contexts. However, there are several convergences in the ambition to redesign farming and food systems, as a lever acting on several topics, and in considering agroecology with a holistic, participatory, multiactor approach for the needed transition.


2019 ◽  
Vol 6 (2) ◽  
pp. 27
Author(s):  
Salvador José Sanchís Gisbert ◽  
Pedro Ponce Gregorio ◽  
Ignacio Peris Blat

Marcel Breuer was in the first year of architectural technicians to graduate from Bauhaus School. The peculiar education he received there allowed him to explore the concept of design in its broadest sense. In his European stage we find, on the most private and small scale, unique solutions for furniture. In his first American stage we see a strong commitment with solutions related to the residential land and, when he earned international recognition, he developed large scale solutions for his public non-residential buildings and urban equipments in locations all over the world. It is strange to see that an architect like him did not have the opportunity to materialize any of his proposals associated with the public space. The 1945 Cambridge Servicemen’s Memorial project, also known as the Memorial War, is the most significant one he developed in his last years in Cambridge. Had it been built, it would have been a valuable example of modernity and contemporary reinterpretation of the monument in the public space.


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