scholarly journals RL mechanisms of short-term plasticity of auditory cortex

2016 ◽  
Author(s):  
Elena Krugliakova ◽  
Alexey Gorin ◽  
Anna Shestakova ◽  
Tommaso Fedele ◽  
Vasily Klucharev
Keyword(s):  
Decision Making ◽  
Auditory Cortex ◽  
Sensory Processing ◽  
Dynamic Environment ◽  
Influential Factors ◽  
Oddball Paradigm ◽  
Fine Grained ◽  
Before And After ◽  
Monetary Incentive Delay ◽  
External Stimuli

AbstractThe decision-making process is exposed to modulatory factors, and, according to the expected value (EV) concept the two most influential factors are magnitude of prospective behavioural outcome and probability of receiving this outcome. The discrepancy between received and predicted outcomes is reflected by the reward prediction error (RPE), which is believed to play a crucial role in learning in dynamic environment. Feedback related negativity (FRN), a frontocentral negative component registered in EEG during feedback presentation, has been suggested as a neural signature of RPE. In modern neurobiological models of decision-making the primary sensory input is assumed to be constant over the time and independent of the evaluation of the option associated to it. In this study we investigated whether the electrophysiological changes in auditory cues perception is modulated by the strengths of reinforcement signal, represented in the EEG as FRN.We quantified the changes in sensory processing through a classical passive oddball paradigm before and after performance a neuroeconomic monetary incentive delay (MID) task. Outcome magnitude and probability were encoded in the physical characteristics of auditory incentive cues. We evaluated the association between individual biomarkers of reinforcement signal (FRN) and the degree of perceptual learning, reflected by changes in auditory ERP components (mismatch negativity and P3a). We observed a significant correlation of MMN and valence - dFRN, reflecting differential processing of gains and omission of gains. Changes in P3a were correlated to probability - dFRN, including information on salience of the outcome, in addition to its valence.MID task performance evokes plastic changes associated with more fine-grained discrimination of auditory anticipatory cues and enhanced involuntary attention switch towards these cues. Observed signatures of neuro-plasticity of the auditory cortex may play an important role in learning and decision-making processes through facilitation of perceptual discrimination of valuable external stimuli. Thus, the sensory processing of options and the evaluation of options are not independent as implicitly assumed by the modern neuroeconomics models of decision-making.

scholarly journals Multimodal sensory processing in Caenorhabditis elegans

Open Biology ◽  
2018 ◽  
Vol 8 (6) ◽  
pp. 180049 ◽  
Author(s):  
Athanasios Metaxakis ◽  
Dionysia Petratou ◽  
Nektarios Tavernarakis
Keyword(s):  
Decision Making ◽  
Caenorhabditis Elegans ◽  
Multisensory Integration ◽  
Sensory Processing ◽  
Molecular Mechanisms ◽  
Physiological State ◽  
Model System ◽  
Neuropsychiatric Disease ◽  
Behavioural Responses ◽  
External Stimuli

Multisensory integration is a mechanism that allows organisms to simultaneously sense and understand external stimuli from different modalities. These distinct signals are transduced into neuronal signals that converge into decision-making neuronal entities. Such decision-making centres receive information through neuromodulators regarding the organism's physiological state and accordingly trigger behavioural responses. Despite the importance of multisensory integration for efficient functioning of the nervous system, and also the implication of dysfunctional multisensory integration in the aetiology of neuropsychiatric disease, little is known about the relative molecular mechanisms. Caenorhabditis elegans is an appropriate model system to study such mechanisms and elucidate the molecular ways through which organisms understand external environments in an accurate and coherent fashion.

scholarly journals Rats optimally accumulate and discount evidence in a dynamic environment

2017 ◽  
Author(s):  
Alex T. Piet ◽  
Ahmed El Hady ◽  
Carlos D. Brody
Keyword(s):  
Decision Making ◽  
Sensory Processing ◽  
Dynamic Environment ◽  
Neural Mechanisms ◽  
Noisy Environments ◽  
Current State ◽  
Adaptive Nature ◽  
Old Evidence ◽  
Long Timescales ◽  
Temporal Accumulation

AbstractHow choices are made within noisy environments is a central question in the neuroscience of decision making. Previous work has characterized temporal accumulation of evidence for decision-making in static environments. However, real-world decision-making involves environments with statistics that change over time. This requires discounting old evidence that may no longer inform the current state of the world. Here we designed a rat behavioral task with a dynamic environment, to probe whether rodents can optimally discount evidence by adapting the timescale over which they accumulate it. Extending existing results about optimal inference in a dynamic environment, we show that the optimal timescale for evidence discounting depends on both the stimulus statistics and noise in sensory processing. We found that when both of these components were taken into account, rats accumulated and temporally discounted evidence almost optimally. Furthermore, we found that by changing the dynamics of the environment, experimenters could control the rats’ accumulation timescale, switching them from accumulating over short timescales to accumulating over long timescales and back. The theoretical framework also makes quantitative predictions regarding the timing of changes of mind in the dynamic environment. This study establishes a quantitative behavioral framework to control and investigate neural mechanisms underlying the adaptive nature of evidence accumulation timescales and changes of mind.

scholarly journals Evaluating the Implementation of the “Build-Back-Better” Concept for Critical Infrastructure Systems: Lessons from Saint-Martin’s Island Following Hurricane Irma

2021 ◽  
Vol 13 (6) ◽  
pp. 3133
Author(s):  
Rita Der Sarkissian ◽  
Anas Dabaj ◽  
Youssef Diab ◽  
Marc Vuillet
Keyword(s):  
Decision Making ◽  
Conceptual Analysis ◽  
Scientific Literature ◽  
Critical Infrastructure ◽  
Methodological Approach ◽  
Infrastructure Systems ◽  
Before And After ◽  
Study Offer ◽  
Hurricane Irma ◽  
Operational Aspects

A limited number of studies in the scientific literature discuss the “Build-Back-Better” (BBB) critical infrastructure (CI) concept. Investigations of its operational aspects and its efficient implementation are even rarer. The term “Better” in BBB is often confusing to practitioners and leads to unclear and non-uniform objectives for guiding accurate decision-making. In an attempt to fill these gaps, this study offers a conceptual analysis of BBB’s operational aspects by examining the term “Better”. In its methodological approach, this study evaluates the state of Saint-Martin’s CI before and after Hurricane Irma and, accordingly, reveals the indicators to assess during reconstruction projects. The proposed methods offer practitioners a guidance tool for planning efficient BBB CI projects or for evaluating ongoing programs through the established BBB evaluation grid. Key findings of the study offer insights and a new conceptual equation of the BBB CI by revealing the holistic and interdisciplinary connotations behind the term “Better” CI: “Build-Back-resilient”, “Build-Back-sustainable”, and “Build-Back-accessible to all and upgraded CI”. The proposed explanations can facilitate the efficient application of BBB for CI by operators, stakeholders, and practitioners and can help them to contextualize the term “Better” with respect to their area and its CI systems.

scholarly journals Stimulus-specific adaptation in auditory thalamus of young and aged awake rats

2013 ◽  
Vol 110 (8) ◽  
pp. 1892-1902 ◽  
Author(s):  
Ben D. Richardson ◽  
Kenneth E. Hancock ◽  
Donald M. Caspary
Keyword(s):  
Young Adult ◽  
Auditory Cortex ◽  
Brown Norway ◽  
Oddball Paradigm ◽  
Adult Rats ◽  
Specific Adaptation ◽  
Auditory Thalamus ◽  
Gating Mechanism ◽  
Medial Geniculate ◽  
Awake Rats

Novel stimulus detection by single neurons in the auditory system, known as stimulus-specific adaptation (SSA), appears to function as a real-time filtering/gating mechanism in processing acoustic information. Particular stimulus paradigms allowing for quantification of a neuron's ability to detect novel or deviant stimuli have been used to examine SSA in the inferior colliculus, medial geniculate body (MGB), and auditory cortex of anesthetized rodents. However, the study of SSA in awake animals is limited to auditory cortex. The present study used individually advanceable tetrodes to record single-unit responses from auditory thalamus (MGB) of awake young adult and aged Fischer Brown Norway (FBN) rats to 1) examine the presence of SSA in the MGB of awake rats and 2) determine whether SSA is altered by aging in MGB. MGB single units in awake FBN rats displayed SSA in response to two stimulus paradigms: the oddball paradigm and a random blocked/interleaved presentation of a set of frequencies. SSA levels were modestly, but nonsignificantly, increased in the nonlemniscal regions of the MGB and at lower stimulus intensities, where 27 of 57 (47%) young adult MGB units displayed SSA. The present findings provide the initial description of SSA in the MGB of awake rats and support SSA as being qualitatively independent of arousal level or anesthetized state. Finally, contrary to previous studies in auditory cortex of anesthetized rats, MGB units in aged rats showed SSA levels indistinguishable from SSA levels in young adult rats, suggesting that SSA in MGB was not impacted by aging in an awake preparation.

scholarly journals Factors Influencing Equity Return Correlations between China’s Pairs of A- and B-Share Markets: Effect of QFII’s Implementation

2017 ◽  
Vol 8 (2) ◽  
pp. 105
Author(s):  
Jung-Lieh Hsiao ◽  
Teng-Tsai Tu ◽  
Mei-Chun Chen
Keyword(s):  
Interest Rate ◽  
Turnover Rate ◽  
Constant Term ◽  
Influential Factors ◽  
Policy Implications ◽  
Return Volatility ◽  
Market Sentiment ◽  
Factors Influencing ◽  
Before And After ◽  
Relative Return

This paper was intended to examine factors influencing the correlations between A- and B-shares of individual firms, and explore the effects of Qualified Foreign Institutional Investor’s (QFII) implementation on correlations. The empirical results show that interest rate differential, relative turnover rate, relative return volatility, and market sentiment had impacts on correlation both before and after the QFII’s implementation. After its implementation, correlations became more sensitive to premium, relative turnover rate and market sentiment. Furthermore, the estimated constant term for overall market correlation became more negative (raw values from -0.3413 to -0.8815), indicating an increasing correlation between A- and B-shares’ returns. The policy implications are that much benefit of diversification into emerging markets such as paired A-and B-shares can be accomplished, together with taking several influential factors into account.

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