A connectivity-constrained computational account of topographic organization in primate high-level visual cortex

Inferotemporal (IT) cortex in humans and other primates is topographically organized, containing multiple hierarchically organized areas selective for particular domains, such as faces and scenes. This organization is commonly viewed in terms of evolved domain-specific visual mechanisms. Here, we develop an alternative, domain-general and developmental account of IT cortical organization. The account is instantiated in interactive topographic networks (ITNs), a class of computational models in which a hierarchy of model IT areas, subject to biologically plausible connectivity-based constraints, learns high-level visual representations optimized for multiple domains. We find that minimizing a wiring cost on spatially organized feedforward and lateral connections, alongside realistic constraints on the sign of neuronal connectivity within model IT, results in a hierarchical, topographic organization. This organization replicates a number of key properties of primate IT cortex, including the presence of domain-selective spatial clusters preferentially involved in the representation of faces, objects, and scenes; columnar responses across separate excitatory and inhibitory units; and generic spatial organization whereby the response correlation of pairs of units falls off with their distance. We thus argue that topographic domain selectivity is an emergent property of a visual system optimized to maximize behavioral performance under generic connectivity-based constraints.

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A connectivity-constrained computational account of topographic organization in high-level visual cortex

10.1101/2021.05.29.446297 ◽

2021 ◽

Author(s):

Nicholas M Blauch ◽

Marlene Behrmann ◽

David Plaut

Keyword(s):

Visual Processing ◽

Spatial Organization ◽

Functional Organization ◽

Spatial Clusters ◽

Feature Extracting ◽

Domain Specific ◽

Visual Processes ◽

Topographic Organization ◽

High Level ◽

Multiple Domain

Inferotemporal cortex (IT) in humans and other primates is topographically organized, with multiple domain-selective areas and other general patterns of functional organization. What factors underlie this organization, and what can this neural arrangement tell us about the mechanisms of high level vision? Here, we present an account of topographic organization involving a computational model with two components: 1) a feature-extracting encoder model of early visual processes, followed by 2) a model of high-level hierarchical visual processing in IT subject to specific biological constraints. In particular, minimizing the wiring cost on spatially organized feedforward and lateral connections within IT, combined with constraining the feedforward processing to be strictly excitatory, results in a hierarchical, topographic organization. This organization replicates a number of key properties of primate IT cortex, including the presence of domain-selective spatial clusters preferentially involved in the representation of faces, objects, and scenes, within-domain topographic organization such as animacy and indoor/outdoor distinctions, and generic spatial organization whereby the response correlation of pairs of units falls off with their distance. The model supports a view in which both domain-specific and domain-general topographic organization arise in the visual system from an optimization process that maximizes behavioral performance while minimizing wiring costs.

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Distributed Simulation Platforms and Data Passing Tools for Natural Hazards Engineering: Reviews, Limitations, and Recommendations

International Journal of Disaster Risk Science ◽

10.1007/s13753-021-00361-7 ◽

2021 ◽

Author(s):

Lichao Xu ◽

Szu-Yun Lin ◽

Andrew W. Hlynka ◽

Hao Lu ◽

Vineet R. Kamat ◽

...

Keyword(s):

Natural Hazards ◽

Data Exchange ◽

Distributed Simulation ◽

Distributed Data ◽

Interactive Simulation ◽

Integrated Simulation ◽

Domain Specific ◽

Advantages And Disadvantages ◽

High Level ◽

Data Passing

AbstractThere has been a strong need for simulation environments that are capable of modeling deep interdependencies between complex systems encountered during natural hazards, such as the interactions and coupled effects between civil infrastructure systems response, human behavior, and social policies, for improved community resilience. Coupling such complex components with an integrated simulation requires continuous data exchange between different simulators simulating separate models during the entire simulation process. This can be implemented by means of distributed simulation platforms or data passing tools. In order to provide a systematic reference for simulation tool choice and facilitating the development of compatible distributed simulators for deep interdependent study in the context of natural hazards, this article focuses on generic tools suitable for integration of simulators from different fields but not the platforms that are mainly used in some specific fields. With this aim, the article provides a comprehensive review of the most commonly used generic distributed simulation platforms (Distributed Interactive Simulation (DIS), High Level Architecture (HLA), Test and Training Enabling Architecture (TENA), and Distributed Data Services (DDS)) and data passing tools (Robot Operation System (ROS) and Lightweight Communication and Marshalling (LCM)) and compares their advantages and disadvantages. Three specific limitations in existing platforms are identified from the perspective of natural hazard simulation. For mitigating the identified limitations, two platform design recommendations are provided, namely message exchange wrappers and hybrid communication, to help improve data passing capabilities in existing solutions and provide some guidance for the design of a new domain-specific distributed simulation framework.

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Temporal Processing Capacity in High-Level Visual Cortex Is Domain Specific

Journal of Neuroscience ◽

10.1523/jneurosci.4822-14.2015 ◽

2015 ◽

Vol 35 (36) ◽

pp. 12412-12424 ◽

Cited By ~ 65

Author(s):

A. Stigliani ◽

K. S. Weiner ◽

K. Grill-Spector

Keyword(s):

Visual Cortex ◽

Temporal Processing ◽

Processing Capacity ◽

Domain Specific ◽

High Level

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Differences in subcortico-cortical interactions identified from connectome and microcircuit models in autism

Nature Communications ◽

10.1038/s41467-021-21732-0 ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Bo-yong Park ◽

Seok-Jun Hong ◽

Sofie L. Valk ◽

Casey Paquola ◽

Oualid Benkarim ◽

...

Keyword(s):

Data Exchange ◽

Computational Models ◽

Simulation Models ◽

Autism Diagnostic Observation Schedule ◽

Supervised Machine Learning ◽

Global Network ◽

Imaging Data ◽

Phenotypic Data ◽

Severity Scores ◽

High Level

AbstractThe pathophysiology of autism has been suggested to involve a combination of both macroscale connectome miswiring and microcircuit anomalies. Here, we combine connectome-wide manifold learning with biophysical simulation models to understand associations between global network perturbations and microcircuit dysfunctions in autism. We studied neuroimaging and phenotypic data in 47 individuals with autism and 37 typically developing controls obtained from the Autism Brain Imaging Data Exchange initiative. Our analysis establishes significant differences in structural connectome organization in individuals with autism relative to controls, with strong between-group effects in low-level somatosensory regions and moderate effects in high-level association cortices. Computational models reveal that the degree of macroscale anomalies is related to atypical increases of recurrent excitation/inhibition, as well as subcortical inputs into cortical microcircuits, especially in sensory and motor areas. Transcriptomic association analysis based on postmortem datasets identifies genes expressed in cortical and thalamic areas from childhood to young adulthood. Finally, supervised machine learning finds that the macroscale perturbations are associated with symptom severity scores on the Autism Diagnostic Observation Schedule. Together, our analyses suggest that atypical subcortico-cortical interactions are associated with both microcircuit and macroscale connectome differences in autism.

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National cardiac registries: a systematic review

European Heart Journal ◽

10.1093/ehjci/ehaa946.3564 ◽

2020 ◽

Vol 41 (Supplement_2) ◽

Author(s):

L Dawson ◽

S Biswas ◽

D Stub ◽

J Lefkovits ◽

L Burchill ◽

...

Keyword(s):

Heart Failure ◽

Coronary Intervention ◽

Quality Registry ◽

Domain Specific ◽

Transcatheter Aortic Valve ◽

System A ◽

Disease Registries ◽

Percutaneous Coronary ◽

Multiple Domains ◽

Disease Specific

Abstract Background Over the last thirty years, there has been exponential growth in the number and scale of national cardiovascular disease registries. We aimed to provide a comprehensive outline of contemporary national cardiac registries across all subspecialties. Methods We performed a systematic literature review by searching OvidMedline in August 2019 to identify registries relating to six pre-specified domains (Table). For inclusion, registries had to be national in nature, actively collecting data, and publishing either peer-reviewed publications or online reports. Results A total of 24,076 records were identified from six domain-specific Medline searches; 24,057 abstracts were screened with 19,435 non-relevant records excluded; 4,624 full texts were screened with 4,473 non-relevant texts excluded; and 151 registries met inclusion criteria representing 51 countries. Of these, 15 related to cardiac surgery, 27 to arrhythmia (17 device, 5 ablation, 7 atrial fibrillation), 21 to congenital heart disease (14 general, 2 interventional, 4 surgical, and 1 disease specific), 43 to coronary disease or percutaneous coronary intervention (22 PCI, 21 CAD), 27 to heart failure (13 heart failure, 5 transplant, 2 mechanical support, 7 disease specific), and 18 related to structural intervention (3 any, 13 transcatheter aortic valve replacement, 2 mitral intervention). Nine national registries (USA, Sweden, Finland, Denmark, UK, Portugal, Norway, Taiwan, and Singapore) covered multiple domains. Quality scoring using the Monash University Clinical Quality Registry Grading System (a composite score of recruitment, and data completeness, definitions, reliability and validation), demonstrated marked heterogeneity in quality between registries. Conclusions Cardiac registries have seen rapid growth, however the use and quality among various subspecialties differs markedly across world regions. Given the multiple benefits, clinicians, funders and health bureaucrats should be encouraged to focus on the range, quality and uptake of national registries. Figure 1 Funding Acknowledgement Type of funding source: None

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Live-cell imaging reveals the spatiotemporal organization of endogenous RNA polymerase II phosphorylation at a single gene

Nature Communications ◽

10.1038/s41467-021-23417-0 ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Linda S. Forero-Quintero ◽

William Raymond ◽

Tetsuya Handa ◽

Matthew N. Saxton ◽

Tatsuya Morisaki ◽

...

Keyword(s):

Rna Polymerase ◽

Rna Polymerase Ii ◽

Single Molecule ◽

Computational Models ◽

Spatial Organization ◽

Fluorescent Antibody ◽

Single Gene ◽

Single Copy ◽

Living Cells ◽

Live Cell

AbstractThe carboxyl-terminal domain of RNA polymerase II (RNAP2) is phosphorylated during transcription in eukaryotic cells. While residue-specific phosphorylation has been mapped with exquisite spatial resolution along the 1D genome in a population of fixed cells using immunoprecipitation-based assays, the timing, kinetics, and spatial organization of phosphorylation along a single-copy gene have not yet been measured in living cells. Here, we achieve this by combining multi-color, single-molecule microscopy with fluorescent antibody-based probes that specifically bind to different phosphorylated forms of endogenous RNAP2 in living cells. Applying this methodology to a single-copy HIV-1 reporter gene provides live-cell evidence for heterogeneity in the distribution of RNAP2 along the length of the gene as well as Serine 5 phosphorylated RNAP2 clusters that remain separated in both space and time from nascent mRNA synthesis. Computational models determine that 5 to 40 RNAP2 cluster around the promoter during a typical transcriptional burst, with most phosphorylated at Serine 5 within 6 seconds of arrival and roughly half escaping the promoter in ~1.5 minutes. Taken together, our data provide live-cell support for the notion of efficient transcription clusters that transiently form around promoters and contain high concentrations of RNAP2 phosphorylated at Serine 5.

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Similarity of Computations Across Domains Does Not Imply Shared Implementation: The Case of Language Comprehension

Current Directions in Psychological Science ◽

10.1177/09637214211046955 ◽

2021 ◽

Vol 30 (6) ◽

pp. 526-534

Author(s):

Evelina Fedorenko ◽

Cory Shain

Keyword(s):

Language Processing ◽

Language Comprehension ◽

Fluid Intelligence ◽

Linguistic Knowledge ◽

Domain Specific ◽

Cognitive Operations ◽

High Level ◽

General Circuits ◽

The Mind ◽

Language Network

Understanding language requires applying cognitive operations (e.g., memory retrieval, prediction, structure building) that are relevant across many cognitive domains to specialized knowledge structures (e.g., a particular language’s lexicon and syntax). Are these computations carried out by domain-general circuits or by circuits that store domain-specific representations? Recent work has characterized the roles in language comprehension of the language network, which is selective for high-level language processing, and the multiple-demand (MD) network, which has been implicated in executive functions and linked to fluid intelligence and thus is a prime candidate for implementing computations that support information processing across domains. The language network responds robustly to diverse aspects of comprehension, but the MD network shows no sensitivity to linguistic variables. We therefore argue that the MD network does not play a core role in language comprehension and that past findings suggesting the contrary are likely due to methodological artifacts. Although future studies may reveal some aspects of language comprehension that require the MD network, evidence to date suggests that those will not be related to core linguistic processes such as lexical access or composition. The finding that the circuits that store linguistic knowledge carry out computations on those representations aligns with general arguments against the separation of memory and computation in the mind and brain.

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ONTOLOGY-BASED GENERATION OF MULTILINGUAL QUESTIONS FOR ASSESSMENT IN MEDICAL EDUCATION

Journal of Teaching English for Specific and Academic Purposes ◽

10.22190/jtesap2001001r ◽

2020 ◽

pp. 001

Author(s):

Maja Radović ◽

Nenad Petrović ◽

Milorad Tošić

Keyword(s):

Medical Education ◽

Knowledge Representation ◽

Teaching And Learning ◽

English Language ◽

Automatic Generation ◽

Assessment Process ◽

Innovative Teaching ◽

Domain Specific ◽

Level Of Automation ◽

High Level

The requirements of state-of-the-art curricula and teaching processes in medical education have brought both new and improved the existing assessment methods. Recently, several promising methods have emerged, among them the Comprehensive Integrative Puzzle (CIP), which shows great potential. However, the construction of such questions requires high efforts of a team of experts and is time-consuming. Furthermore, despite the fact that English language is accepted as an international language, for educational purposes there is also a need for representing data and knowledge in native language. In this paper, we present an approach for automatic generation of CIP assessment questions based on using ontologies for knowledge representation. In this way, it is possible to provide multilingual support in the teaching and learning process because the same ontological concept can be applied to corresponding language expressions in different languages. The proposed approach shows promising results indicated by dramatic speeding up of construction of CIP questions compared to manual methods. The presented results represent a strong indication that adoption of ontologies for knowledge representation may enable scalability in multilingual domain-specific education regardless of the language used. High level of automation in the assessment process proven on the CIP method in medical education as one of the most challenging domains, promises high potential for new innovative teaching methodologies in other educational domains as well.

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Tuning in scene-preferring cortex for mid-level visual features gives rise to selectivity across multiple levels of stimulus complexity

10.1101/2021.09.24.461733 ◽

2021 ◽

Author(s):

Shi Pui Donald Li ◽

Michael F. Bonner

Keyword(s):

Real World ◽

Computational Models ◽

Visual Stream ◽

Computational Theory ◽

Low Level ◽

Multiple Levels ◽

High Level ◽

Hierarchical Encoding ◽

Natural Statistics ◽

High Throughput Experiments

The scene-preferring portion of the human ventral visual stream, known as the parahippocampal place area (PPA), responds to scenes and landmark objects, which tend to be large in real-world size, fixed in location, and inanimate. However, the PPA also exhibits preferences for low-level contour statistics, including rectilinearity and cardinal orientations, that are not directly predicted by theories of scene- and landmark-selectivity. It is unknown whether these divergent findings of both low- and high-level selectivity in the PPA can be explained by a unified computational theory. To address this issue, we fit hierarchical computational models of mid-level tuning to the image-evoked fMRI responses of the PPA, and we performed a series of high-throughput experiments on these models. Our findings show that hierarchical encoding models of the PPA exhibit emergent selectivity across multiple levels of complexity, giving rise to high-level preferences along dimensions of real-world size, fixedness, and naturalness/animacy as well as low-level preferences for rectilinear shapes and cardinal orientations. These results reconcile disparate theories of PPA function in a unified model of mid-level visual representation, and they demonstrate how multifaceted selectivity profiles naturally emerge from the hierarchical computations of visual cortex and the natural statistics of images.

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