scholarly journals Medial temporal and prefrontal cortices encode structural task representations at different levels of abstraction

2021 ◽  
Author(s):  
Sam C Berens ◽  
Chris M Bird
Keyword(s):  
Prefrontal Cortex ◽  
Medial Temporal Lobe ◽  
Levels Of Abstraction ◽  
Relational Information ◽  
Structural Relationships ◽  
Pattern Similarity ◽  
Task Features ◽  
Task Representations ◽  
Different Levels ◽  
Inference Task

Memory generalisations may be underpinned by either encoding- or retrieval-based mechanisms. We used a transitive inference task to investigate whether these generalisation mechanisms are influenced by progressive vs randomly interleaved training, and overnight consolidation. On consecutive days, participants learnt pairwise discriminations from two transitive hierarchies before being tested during fMRI. Inference performance was consistently better following progressive training, and for pairs further apart in the transitive hierarchy. BOLD pattern similarity correlated with hierarchical distances in the medial temporal lobe (MTL) and medial prefrontal cortex (MPFC). These results are consistent with the use of representations that directly encode structural relationships between different task features. Furthermore, BOLD patterns in MPFC were similar across the two independent hierarchies. We conclude that humans preferentially employ encoding-based mechanisms to store map-like relational codes that can be used for memory generalisation. While both MTL and MPFC support these representations, the MPFC encodes more abstract relational information.

Children show adult-like hippocampal pattern separation for familiar but not novel events

2020 ◽  
Author(s):  
Susan L. Benear ◽  
Elizabeth A. Horwath ◽  
Emily Cowan ◽  
M. Catalina Camacho ◽  
Chi Ngo ◽  
...  
Keyword(s):  
Episodic Memory ◽  
Temporal Lobe ◽  
Medial Temporal Lobe ◽  
Developmental Change ◽  
Pattern Separation ◽  
Developmental Changes ◽  
Similarity Analysis ◽  
Separation Processes ◽  
Parahippocampal Cortex ◽  
Pattern Similarity

The medial temporal lobe (MTL) undergoes critical developmental change throughout childhood, which aligns with developmental changes in episodic memory. We used representational similarity analysis to compare neural pattern similarity for children and adults in hippocampus and parahippocampal cortex during naturalistic viewing of clips from the same movie or different movies. Some movies were more familiar to participants than others. Neural pattern similarity was generally lower for clips from the same movie, indicating that related content taxes pattern separation-like processes. However, children showed this effect only for movies with which they were familiar, whereas adults showed the effect consistently. These data suggest that children need more exposures to stimuli in order to show mature pattern separation processes.

scholarly journals Model-Driven Architectural Framework towards Safe and Secure Nuclear Power Reactors

Sensors ◽  
2021 ◽  
Vol 21 (15) ◽  
pp. 5136
Author(s):  
Bassem Ouni ◽  
Christophe Aussagues ◽  
Saadia Dhouib ◽  
Chokri Mraidha
Keyword(s):  
Nuclear Power ◽  
Nuclear Reactors ◽  
System Development ◽  
Levels Of Abstraction ◽  
Model Driven ◽  
Case System ◽  
Architectural Framework ◽  
Performance Check ◽  
High Level ◽  
Different Levels

Sensor-based digital systems for Instrumentation and Control (I&C) of nuclear reactors are quite complex in terms of architecture and functionalities. A high-level framework is highly required to pre-evaluate the system’s performance, check the consistency between different levels of abstraction and address the concerns of various stakeholders. In this work, we integrate the development process of I&C systems and the involvement of stakeholders within a model-driven methodology. The proposed approach introduces a new architectural framework that defines various concepts, allowing system implementations and encompassing different development phases, all actors, and system concerns. In addition, we define a new I&C Modeling Language (ICML) and a set of methodological rules needed to build different architectural framework views. To illustrate this methodology, we extend the specific use of an open-source system engineering tool, named Eclipse Papyrus, to carry out many automation and verification steps at different levels of abstraction. The architectural framework modeling capabilities will be validated using a realistic use case system for the protection of nuclear reactors. The proposed framework is able to reduce the overall system development cost by improving links between different specification tasks and providing a high abstraction level of system components.

Thalamic pathways underlying prefrontal cortex–medial temporal lobe oscillatory interactions

2015 ◽  
Vol 38 (1) ◽  
pp. 3-12 ◽  
Author(s):  
Nicholas A. Ketz ◽  
Ole Jensen ◽  
Randall C. O’Reilly
Keyword(s):  
Prefrontal Cortex ◽  
Temporal Lobe ◽  
Medial Temporal Lobe

Moral und Hypermoral

2016 ◽  
Author(s):  
Arnold Gehlen
Keyword(s):  
Behavioral Science ◽  
Philosophical Anthropology ◽  
The State ◽  
Sociological Research ◽  
Levels Of Abstraction ◽  
The Enlightenment ◽  
Broad Scope ◽  
Magnum Opus ◽  
Different Levels ◽  
Evolutionary Interpretation

Moral and Hypermoral, Arnold Gehlen´s final book-length publication, is an elaboration on basic theses which had initially been brought forward in Gehlen´s anthropological magnum opus "Der Mensch". In this respect, this draft of a "pluralistic ethics" is conceived as an elaboration on as well as a concretion of his doctrine of man. In this book, Gehlen set himself the task of combining anthropology, behavioral science, and sociology in a “genealogy of morality”, thus exposing four interdependent forms of ethics: from an ethos of "reciprocity" via “eudaimonism” and “humanitarianism” to an ethos of institutions, including the state. Gehlen made a decisive stand against the "abstract ethics of the Enlightenment": systematically, his book is primarily an anthropological justification of ethics, conceived as a "majority of moral authorities" and "social regulations." These are not subjected to an evolutionary interpretation, that is, as progress from an ethics of proximity to a world-encompassing morality. Moralities, whether based on instinct or arising from the needs of particular institutions, are always culturally shaped and set on different levels of abstraction. With its broad scope, the book belongs in the context of basic philosophical-sociological research known as philosophical anthropology.

scholarly journals The Parietal Cortex in Sensemaking: The Dissociation of Multiple Types of Spatial Information

2013 ◽  
Vol 2013 ◽  
pp. 1-14 ◽  
Author(s):  
Yanlong Sun ◽  
Hongbin Wang
Keyword(s):  
Parietal Cortex ◽  
Spatial Information ◽  
Mathematical Thinking ◽  
Hierarchical Organization ◽  
Levels Of Abstraction ◽  
Perceptual Analysis ◽  
Different Types ◽  
Sensemaking Process ◽  
Network Simulations ◽  
Different Levels

According to the data-frame theory, sensemaking is a macrocognitive process in which people try to make sense of or explain their observations by processing a number of explanatory structures called frames until the observations and frames become congruent. During the sensemaking process, the parietal cortex has been implicated in various cognitive tasks for the functions related to spatial and temporal information processing, mathematical thinking, and spatial attention. In particular, the parietal cortex plays important roles by extracting multiple representations of magnitudes at the early stages of perceptual analysis. By a series of neural network simulations, we demonstrate that the dissociation of different types of spatial information can start early with a rather similar structure (i.e., sensitivity on a common metric), but accurate representations require specific goal-directed top-down controls due to the interference in selective attention. Our results suggest that the roles of the parietal cortex rely on the hierarchical organization of multiple spatial representations and their interactions. The dissociation and interference between different types of spatial information are essentially the result of the competition at different levels of abstraction.

scholarly journals Hippocampal–diencephalic–cingulate networks for memory and emotion: An anatomical guide

2017 ◽  
Vol 1 ◽  
pp. 239821281772344 ◽  
Author(s):  
Emma J. Bubb ◽  
Lisa Kinnavane ◽  
John P. Aggleton
Keyword(s):  
Prefrontal Cortex ◽  
Medial Temporal Lobe ◽  
Current Knowledge ◽  
Hippocampal Formation ◽  
Retrosplenial Cortex ◽  
Thalamic Nuclei ◽  
Mammillary Bodies ◽  
Individual Site ◽  
Multi Stage ◽  
Anterior Thalamic Nuclei

This review brings together current knowledge from tract tracing studies to update and reconsider those limbic connections initially highlighted by Papez for their presumed role in emotion. These connections link hippocampal and parahippocampal regions with the mammillary bodies, the anterior thalamic nuclei, and the cingulate gyrus, all structures now strongly implicated in memory functions. An additional goal of this review is to describe the routes taken by the various connections within this network. The original descriptions of these limbic connections saw their interconnecting pathways forming a serial circuit that began and finished in the hippocampal formation. It is now clear that with the exception of the mammillary bodies, these various sites are multiply interconnected with each other, including many reciprocal connections. In addition, these same connections are topographically organised, creating further subsystems. This complex pattern of connectivity helps explain the difficulty of interpreting the functional outcome of damage to any individual site within the network. For these same reasons, Papez’s initial concept of a loop beginning and ending in the hippocampal formation needs to be seen as a much more complex system of hippocampal–diencephalic–cingulate connections. The functions of these multiple interactions might be better viewed as principally providing efferent information from the posterior medial temporal lobe. Both a subcortical diencephalic route (via the fornix) and a cortical cingulate route (via retrosplenial cortex) can be distinguished. These routes provide indirect pathways for hippocampal interactions with prefrontal cortex, with the preponderance of both sets of connections arising from the more posterior hippocampal regions. These multi-stage connections complement the direct hippocampal projections to prefrontal cortex, which principally arise from the anterior hippocampus, thereby creating longitudinal functional differences along the anterior–posterior plane of the hippocampus.

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