scholarly journals The neurocognitive basis of knowledge about object identity and events: dissociations reflect opposing effects of semantic coherence and control

2019 ◽  
Vol 375 (1791) ◽  
pp. 20190300 ◽  
Author(s):  
Elizabeth Jefferies ◽  
Hannah Thompson ◽  
Piers Cornelissen ◽  
Jonathan Smallwood
Keyword(s):  
Semantic Processing ◽  
Semantic Network ◽  
Angular Gyrus ◽  
Middle Temporal Gyrus ◽  
Control Network ◽  
Object Identity ◽  
Automatic Retrieval ◽  
Semantic Coherence ◽  
Opposing Effects ◽  
And Control

Semantic memory encompasses knowledge of specific objects and their diverse associations, but the mechanisms that allow us to retrieve aspects of knowledge required for a given task are poorly understood. The dual hub theory suggests that separate semantic stores represent knowledge of (i) taxonomic categories (in the anterior temporal lobes, ATL) and (ii) thematic associations (in angular gyrus, AG or posterior middle temporal gyrus, pMTG). Alternatively, the controlled semantic cognition (CSC) framework suggests that semantic processing emerges from the flexible interaction of heteromodal semantic representations in ATL with a semantic control network, which includes pMTG as well as prefrontal regions. According to this view, ATL supports patterns of coherent auto-associative retrieval, while semantic control sites respond when ongoing conceptual activation needs to be altered to suit the task or context. These theories make different predictions about the nature of functional dissociations within the semantic network. We review evidence for these claims across multiple methods. First, we show ATL is sensitive to the strength of thematic associations as well as taxonomic relations. Next, we document functional dissociations between AG and pMTG: rather than these regions acting as comparable thematic hubs, AG is allied to the default mode network and supports more ‘automatic’ retrieval, while pMTG responds when control demands are high. However, the semantic control network, including pMTG, also shows a greater response to events/actions and verbs, supporting the claims of both theories. We propose that tasks tapping event semantics often require greater shaping of conceptual retrieval than comparison tasks, because these elements of our knowledge are inherently flexible, with relevant features depending on the context. In this way, the CSC account might be able to account for findings that suggest both a process and a content distinction within the semantic network. This article is part of the theme issue ‘Towards mechanistic models of meaning composition’.

scholarly journals The Neural Correlates of Semantic Control Revisited

2020 ◽  
Author(s):  
Rebecca L. Jackson
Keyword(s):  
Semantic Network ◽  
Meta Analysis ◽  
Inferior Frontal Gyrus ◽  
Temporal Cortex ◽  
Neural Correlates ◽  
Middle Temporal Gyrus ◽  
Control Network ◽  
Temporal Region ◽  
List Type ◽  
Semantic Cognition

AbstractSemantic control, the ability to selectively access and manipulate meaningful information on the basis of context demands, is a critical component of semantic cognition. The precise neural correlates of semantic control are disputed, with particular debate surrounding parietal involvement, the spatial extent of the posterior temporal contribution and network lateralisation. Here semantic control is revisited, utilising improved analysis techniques and a decade of additional data to refine our understanding of the network. A meta-analysis of 876 peaks over 121 contrasts illuminated a left-focused network consisting of inferior frontal gyrus, posterior middle temporal gyrus, posterior inferior temporal gyrus and dorsomedial prefrontal cortex. This extended the temporal region implicated, and found no parietal involvement. Although left-lateralised overall, relative lateralisation varied across the implicated regions. Supporting analyses confirmed the multimodal nature of the semantic control network and situated it within the wider set of regions implicated in semantic cognition.Highlights➢A multimodal semantic control network was delineated with formal meta-analyses➢Semantic control recruits inferior and medial frontal and posterior temporal cortex➢A large extent of posterior temporal cortex was implicated and no parietal regions➢Semantic control is left-lateralised but regions show differential lateralisation➢The semantic control regions were situated in the context of the wider semantic network

The Predigest Project of Vehicle-Bone Multimedia Transmission and Control Network Based on FPGA

2012 ◽  
Vol 203 ◽  
pp. 62-66
Author(s):  
Hong Li ◽  
Qiao Zhen Hou
Keyword(s):  
Network Control ◽  
Control Network ◽  
Network System ◽  
Multimedia Transmission ◽  
Transmission Control ◽  
Hardware Platform ◽  
Arm Processor ◽  
Interface Module ◽  
Fpga Chip ◽  
And Control

The design uses 32 ARM processor S3C44B0X and Spartan™ -3E500 FPGA chip produced by Xinlinx company for setting up the hardware platform, and integrates the camera, GPS module, MiniGUI interface module. And realized bus vehicle mounted multimedia transmission control network control based on MOST. All of these are in the purpose of achieving a Predigest Project of vehicle-bone multimedia transmission and control network based on FPGA. The experiment indicated that, the transmission and control network system constructed by S3C44B0X and Spartan - 3E500 FPGA is low cast, simple and reliable.

scholarly journals Control/Network Codesign Basics for IP-Based Shared Networks

2011 ◽  
Vol 2011 ◽  
pp. 1-23 ◽  
Author(s):  
Miguel Díaz-Cacho Medina ◽  
Emma Delgado Romero ◽  
Antonio Barreiro Blas
Keyword(s):  
Control Systems ◽  
Networked Control Systems ◽  
Transmission Rate ◽  
Design Parameters ◽  
Control Network ◽  
Transport Protocol ◽  
Test Platform ◽  
Shared Networks ◽  
The Stability ◽  
And Control

Network and control relationship is an essential aspect in the design of networked control systems (NCSs). The design parameters are mainly centered in the transmission rate and in the packet structure, and some studies have been made to determine how transmission rate affects the network delay and consequently the stability of the control. In Internet, these analysis are mathematically complex due to the large number of different potential scenarios. Using empirical methods, this work deduces that the transmission scheduling problem of an NCS can be solved by designing an appropriate transport protocol, taken into account high and periodic sampling rates. The transport protocol features are determined by simulation, using a new test platform based on the NS2 network simulation suite, to develop control/network codesign solutions. Conclusions of this paper are that the transport features are packet-loss-based flow control, best effort, and fairness, supplemented by a packet priority scheme.

scholarly journals Algebra dissociates from arithmetic in the brain semantic network

2022 ◽  
Vol 18 (1) ◽  
Author(s):  
Dazhi Cheng ◽  
Mengyi Li ◽  
Jiaxin Cui ◽  
Li Wang ◽  
Naiyi Wang ◽  
...  
Keyword(s):  
Functional Connectivity ◽  
Supplementary Motor Area ◽  
Semantic Network ◽  
Brain Activation ◽  
Motor Area ◽  
Angular Gyrus ◽  
Single Trial ◽  
Positive Functional ◽  
Brain Behavior ◽  
The Brain

Abstract Background Mathematical expressions mainly include arithmetic (such as 8 − (1 + 3)) and algebra (such as a − (b + c)). Previous studies have shown that both algebraic processing and arithmetic involved the bilateral parietal brain regions. Although previous studies have revealed that algebra was dissociated from arithmetic, the neural bases of the dissociation between algebraic processing and arithmetic is still unclear. The present study uses functional magnetic resonance imaging (fMRI) to identify the specific brain networks for algebraic and arithmetic processing. Methods Using fMRI, this study scanned 30 undergraduates and directly compared the brain activation during algebra and arithmetic. Brain activations, single-trial (item-wise) interindividual correlation and mean-trial interindividual correlation related to algebra processing were compared with those related to arithmetic. The functional connectivity was analyzed by a seed-based region of interest (ROI)-to-ROI analysis. Results Brain activation analyses showed that algebra elicited greater activation in the angular gyrus and arithmetic elicited greater activation in the bilateral supplementary motor area, left insula, and left inferior parietal lobule. Interindividual single-trial brain-behavior correlation revealed significant brain-behavior correlations in the semantic network, including the middle temporal gyri, inferior frontal gyri, dorsomedial prefrontal cortices, and left angular gyrus, for algebra. For arithmetic, the significant brain-behavior correlations were located in the phonological network, including the precentral gyrus and supplementary motor area, and in the visuospatial network, including the bilateral superior parietal lobules. For algebra, significant positive functional connectivity was observed between the visuospatial network and semantic network, whereas for arithmetic, significant positive functional connectivity was observed only between the visuospatial network and phonological network. Conclusion These findings suggest that algebra relies on the semantic network and conversely, arithmetic relies on the phonological and visuospatial networks.

scholarly journals A Cost-Effective Embedded Platform for Greenhouse Environment Control and Remote Monitoring

Agronomy ◽  
2020 ◽  
Vol 10 (7) ◽  
pp. 936 ◽  
Author(s):  
Radu L. Sumalan ◽  
Nicoleta Stroia ◽  
Daniel Moga ◽  
Vlad Muresan ◽  
Alexandru Lodin ◽  
...  
Keyword(s):  
Remote Monitoring ◽  
Low Cost ◽  
Cost Effective ◽  
Agricultural System ◽  
Control Network ◽  
Monitoring And Control ◽  
Embedded Platform ◽  
Environment Control ◽  
Functional Features ◽  
And Control

This paper presents the development of a cost-effective automatic system for greenhouse environment control. The architectural and functional features were analyzed in the context of the realization of a controlled-environment agricultural system through all its stages: installation, deployment of the software, integration, maintenance, crop control strategy setup and daily operation of the grower. The proposed embedded platform provides remote monitoring and control of the greenhouse environment and is implemented as a distributed sensing and control network integrating wired and wireless nodes. All nodes were built with low-cost, low-power microcontrollers. The key issues that were addressed include the energy-efficient control, the robustness of the distributed control network to faults and a low-cost hardware implementation. The translation of the supervisory growth-planning information to the operational (control network) level is achieved through a specific architecture residing on a crop planning module (CPM) and an interfacing block (IB). A suite of software applications with flows and interfaces developed from a grower-centric perspective was designed and implemented on a multi-tier architecture. The operation of the platform was validated through implementation of sensing and control nodes, application of software for configuration and visualization, and deployment in typical greenhouses.

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