Impact of Adaptation on Thalamic Neurons' Computational Role of Conveying Contextual Information about Paired-Pulse Tactile Stimuli

2021 ◽  
Author(s):  
Chen Liu
Keyword(s):  
Contextual Information ◽  
Thalamic Neurons ◽  
Paired Pulse ◽  
Tactile Stimuli

When Feature Information Comes First! Early Processing of Inverted Faces

Perception ◽  
10.1068/p5192 ◽  
2005 ◽  
Vol 34 (9) ◽  
pp. 1117-1134 ◽  
Author(s):  
Claus-Christian Carbon ◽  
Helmut Leder
Keyword(s):  
Information Processing ◽  
Face Recognition ◽  
Face Processing ◽  
Contextual Information ◽  
Presentation Time ◽  
Early Processing ◽  
Feature Information ◽  
Short Presentation Time ◽  
Short Presentation

We investigated the early stages of face recognition and the role of featural and holistic face information. We exploited the fact that, on inversion, the alienating disorientation of the eyes and mouth in thatcherised faces is hardly detectable. This effect allows featural and holistic information to be dissociated and was used to test specific face-processing hypotheses. In inverted thatcherised faces, the cardinal features are already correctly oriented, whereas in undistorted faces, the whole Gestalt is coherent but all information is disoriented. Experiment 1 and experiment 3 revealed that, for inverted faces, featural information processing precedes holistic information. Moreover, the processing of contextual information is necessary to process local featural information within a short presentation time (26 ms). Furthermore, for upright faces, holistic information seems to be available faster than for inverted faces (experiment 2). These differences in processing inverted and upright faces presumably cause the differential importance of featural and holistic information for inverted and upright faces.

IMAGE RECOGNITION BY INTEGRATION OF CONNECTIONIST AND SYMBOLIC APPROACHES

1995 ◽  
Vol 09 (03) ◽  
pp. 485-515 ◽  
Author(s):  
F. ROLI ◽  
S. B. SERPICO ◽  
G. VERNAZZA
Keyword(s):  
Image Recognition ◽  
Magnetic Resonance Image ◽  
Contextual Information ◽  
Recognition System ◽  
Recognition Problem ◽  
Training Process ◽  
Neural Architecture ◽  
Recognition Phase ◽  
Abstraction Levels

This paper presents a methodology for integrating connectionist and symbolic approaches to 2D image recognition. The proposed integration paradigm exploits the synergy of the two approaches for both the training and the recognition phases of an image recognition system. In the training phase, a symbolic module provides an approximate solution to a given image-recognition problem in terms of symbolic models. Such models are hierarchically organized into different abstraction levels, and include contextual descriptions. After mapping such models into a complex neural architecture, a neural training process is carried out to optimize the solution of the recognition problem. The so-obtained neural networks are used during the recognition phase for pattern classification. In this phase, the role of symbolic modules consists of managing complex aspects of information processing: abstraction levels, contextual information, and global recognition hypotheses. A hybrid system implementing the proposed integration paradigm is presented, and its advantages over single approaches are assessed. Results on Magnetic Resonance image recognition are reported, and comparisons with some well-known classifiers are made.

scholarly journals Neuropsychological assessment and virtual reality training of social prediction in patients with cerebellar malformation

2021 ◽  
Author(s):  
Cosimo Urgesi ◽  
Niccolò Butti ◽  
Alessandra Finisguerra ◽  
Emilia Biffi ◽  
Enza Maria Valente ◽  
...  
Keyword(s):  
Virtual Reality ◽  
Social Cognition ◽  
Contextual Information ◽  
Predictive Coding ◽  
Predictive Processing ◽  
Cerebellar Malformation ◽  
Use Context ◽  
Predictive Role ◽  
Social Prediction

AbstractIt has been proposed that impairments of the predictive function exerted by the cerebellum may account for social cognition deficits. Here, we integrated cerebellar functions in a predictive coding framework to elucidate how cerebellar alterations could affect the predictive processing of others’ behavior. Experiment 1 demonstrated that cerebellar patients were impaired in relying on contextual information during action prediction, and this impairment was significantly associated with social cognition abilities. Experiment 2 indicated that patients with cerebellar malformation showed a domain-general deficit in using contextual information to predict both social and physical events. Experiment 3 provided first evidence that a social-prediction training in virtual reality could boost the ability to use context-based predictions to understand others’ intentions. These findings shed new light on the predictive role of the cerebellum and its contribution to social cognition, paving the way for new approaches to the rehabilitation of the Cerebellar Cognitive Affective Syndrome.

scholarly journals Integration of signals from different cortical areas in higher order thalamic neurons

2021 ◽  
Vol 118 (30) ◽  
pp. e2104137118
Author(s):  
Vandana Sampathkumar ◽  
Andrew Miller-Hansen ◽  
S. Murray Sherman ◽  
Narayanan Kasthuri
Keyword(s):  
Higher Order ◽  
Cortical Layer ◽  
Thalamic Neurons ◽  
Cortical Areas ◽  
Medial Nucleus ◽  
Afferent Information ◽  
Posterior Medial Nucleus ◽  
Depth And Complexity ◽  
Genetic Labeling

Higher order thalamic neurons receive driving inputs from cortical layer 5 and project back to the cortex, reflecting a transthalamic route for corticocortical communication. To determine whether or not individual neurons integrate signals from different cortical populations, we combined electron microscopy “connectomics” in mice with genetic labeling to disambiguate layer 5 synapses from somatosensory and motor cortices to the higher order thalamic posterior medial nucleus. A significant convergence of these inputs was found on 19 of 33 reconstructed thalamic cells, and as a population, the layer 5 synapses were larger and located more proximally on dendrites than were unlabeled synapses. Thus, many or most of these thalamic neurons do not simply relay afferent information but instead integrate signals as disparate in this case as those emanating from sensory and motor cortices. These findings add further depth and complexity to the role of the higher order thalamus in overall cortical functioning.

Muscarinic presynaptic modulation in GABAergic pallidal synapses of the rat

2015 ◽  
Vol 113 (3) ◽  
pp. 796-807 ◽  
Author(s):  
Ricardo Hernández-Martínez ◽  
José J. Aceves ◽  
Pavel E. Rueda-Orozco ◽  
Teresa Hernández-Flores ◽  
Omar Hernández-González ◽  
...  
Keyword(s):  
Receptor Agonist ◽  
Projection Neurons ◽  
Quantal Content ◽  
Short Term ◽  
Paired Pulse ◽  
Short Term Plasticity ◽  
Striatal Projection Neurons ◽  
Muscarinic Cholinergic ◽  
Muscarinic Modulation

The external globus pallidus (GPe) is central for basal ganglia processing. It expresses muscarinic cholinergic receptors and receives cholinergic afferents from the pedunculopontine nuclei (PPN) and other regions. The role of these receptors and afferents is unknown. Muscarinic M1-type receptors are expressed by synapses from striatal projection neurons (SPNs). Because axons from SPNs project to the GPe, one hypothesis is that striatopallidal GABAergic terminals may be modulated by M1 receptors. Alternatively, some M1 receptors may be postsynaptic in some pallidal neurons. Evidence of muscarinic modulation in any of these elements would suggest that cholinergic afferents from the PPN, or other sources, could modulate the function of the GPe. In this study, we show this evidence using striatopallidal slice preparations: after field stimulation in the striatum, the cholinergic muscarinic receptor agonist muscarine significantly reduced the amplitude of inhibitory postsynaptic currents (IPSCs) from synapses that exhibited short-term synaptic facilitation. This inhibition was associated with significant increases in paired-pulse facilitation, and quantal content was proportional to IPSC amplitude. These actions were blocked by atropine, pirenzepine, and mamba toxin-7, suggesting that receptors involved were M1. In addition, we found that some pallidal neurons have functional postsynaptic M1 receptors. Moreover, some evoked IPSCs exhibited short-term depression and a different kind of modulation: they were indirectly modulated by muscarine via the activation of presynaptic cannabinoid CB1 receptors. Thus pallidal synapses presenting distinct forms of short-term plasticity were modulated differently.

scholarly journals Grammar and context in Functional Discourse Grammar

Pragmatics ◽  
2014 ◽  
Vol 24 (2) ◽  
pp. 203-227 ◽  
Author(s):  
Kees Hengeveld ◽  
J. Lachlan Mackenzie
Keyword(s):  
Contextual Information ◽  
Guiding Principle ◽  
Exchange Of Information ◽  
Direct Exchange ◽  
Proper Functioning ◽  
European Portuguese ◽  
Linguistic Representations ◽  
Discourse Grammar

This article presents a proposal for the organization of the Contextual Component in Functional Discourse Grammar. A guiding principle in this proposal is that, given the fact that Functional Discourse Grammar is a theory of grammar, the Contextual Component should provide the information that is necessary for a proper functioning of the grammar rather than aim at an exhaustive specification of all the information that plays a role in interpreting linguistic expressions. The Contextual Component contains situational and discursive information and is organized in different strata that correspond to the interpersonal, representational, morphosyntactic, and phonological levels of representation within the grammar. The contextual representations make use of the same formalizations as the corresponding linguistic representations, thus allowing for direct exchange of information between the Grammatical and the Contextual Components. Thus exchange of information is handled by an interface called the contextualizer. The article illustrates the functioning of this model by analyzing the role of contextual information with respect to three grammatical phenomena in three different languages: Unexpressed arguments in Turkish, English too, and answers to yes/no questions in European Portuguese.

Translation of strategic ambiguity: A relevance-theoretic analysis

2018 ◽  
Vol 54 (1) ◽  
pp. 1-35 ◽  
Author(s):  
Rasheed S. Al-Jarrah ◽  
Ahmad M. Abu-Dalu ◽  
Hisham Obiedat
Keyword(s):  
Conceptual Framework ◽  
Ambiguity Resolution ◽  
Contextual Information ◽  
Relevance Theory ◽  
Original Text ◽  
Theoretic Analysis ◽  
Strategic Ambiguity ◽  
The One ◽  
Point Of Departure

AbstractThe purpose of our current research is to see how Relevance Theory can handle one specific translation problem, namely strategic ambiguous structures. Concisely, we aim to provide a conceptual framework as to how the translator should cope with a pervasive ambiguity problem at the discoursal level. The point of departure from probably all previous models of analysis is that a relevance-theoretic analysis would, we believe, require that a “good” translation benotthe one that representsan interpretationof the text, but the one which leaves the door open for all interpretations which the original text provides evidence for. Hence,the role of translator is not to ‘interpret’ but to ‘translate’. If this is true, ambiguity resolution should not be a viable alternative. In other words, what the translator should do is empower the audience with all it takes to let them work out all the explicatures (linguistically inferred meanings) and entertain themselves with the implicatures (contextually inferred meanings) of the original. Direct Translation, along the lines laid down by Gutt (1991/2000), is the method of translation which can, we believe, bring about the desired results because “it tries to provide readers with contextual information that enables them to draw their own inferences” (Smith 2000: 92).

PP298 Scottish Health Technologies Group (SHTG) Adaptations: Utilizing Other Agencies’ HTAs In Scotland

2021 ◽  
Vol 37 (S1) ◽  
pp. 34-34
Author(s):  
Neil Anand ◽  
Evan Campbell ◽  
Tracey Macgann ◽  
Joanna Kelly ◽  
Julie Calvert
Keyword(s):  
Contextual Information ◽  
New Product ◽  
Appraisal Committee ◽  
Health Technologies ◽  
Modified Delphi ◽  
Delphi Approach ◽  
Consultation Group ◽  
Clinical Engagement ◽  
Inform Decision Making

IntroductionHealth Technology Assessment (HTA) is an important but time-consuming process to inform decision-making. Following requests from stakeholders in Scotland to provide advice on technologies that had recently undergone HTA in other jurisdictions, SHTG recognized a gap in their ‘product menu’. Colleagues within the SHTG team devised a mechanism through which an original HTA could be adapted for Scotland, taking into account local contextual factors.MethodsSHTG Adaptations comprise the following: i) assessment of the original HTA using the EUnetHTA HTA Adaptation Toolkit and checklist; ii) draft Adaptation using the outcome of the assessment and contextual information for Scotland; iii) consultation group of relevant Scottish clinicians is provided with the original HTA and draft SHTG Adaptation; iv) modified Delphi approach (max. three rounds of questioning) is used to ascertain the relevance of the original HTA to Scotland; v) the Adaptation is submitted to SHTG Council for endorsement.ResultsSHTG Adaptations have a timeline of 2–3 months, three have been published since this product was launched. The process has run smoothly with excellent clinical engagement from across NHS Scotland. Key learning focusses on the role of the SHTG Council (i.e. appraisal committee) in this process and in handling of expert opinion of evidence which has already been appraised by another agency.ConclusionsThe SHTG Adaptation is a new product which offers a timely assessment and utilization of an HTA from another agency.

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