scholarly journals A post-decisional neural marker of confidence predicts information-seeking in decision-making

2018 ◽  
Author(s):  
Kobe Desender ◽  
Peter Murphy ◽  
Annika Boldt ◽  
Tom Verguts ◽  
Nick Yeung
Keyword(s):  
Information Seeking ◽  
Time Window ◽  
Adaptive Strategy ◽  
Theoretical Work ◽  
Confidence Judgment ◽  
Final Decision ◽  
Time Resolved ◽  
Perceptual Decision ◽  
Scalp Eeg ◽  
Neural Marker

AbstractTheoretical work predicts that decisions made with low confidence should lead to increased information-seeking. This is an adaptive strategy because it can increase the quality of a decision, and previous behavioral work has shown that decision-makers engage in such confidence-driven information seeking. The present study aimed to characterize the neural markers that mediate the relationship between confidence and information-seeking. A paradigm was used in which human participants made an initial perceptual decision, and then decided whether or not they wanted to sample more evidence before committing to a final decision and confidence judgment. Pre-decisional and post-decisional ERP components were similarly modulated by the level of confidence and by information-seeking choices. Time-resolved multivariate decoding of scalp EEG signals first revealed that information-seeking choices could be decoded from the time of the initial decision to the time of the subsequent information-seeking choice (within-condition decoding). No above-chance decoding was visible in the pre-response time window. Crucially, a classifier trained to decode high versus low confidence predicted information-seeking choices after the initial perceptual decision (across-condition decoding). This time window corresponds to that of a post-decisional neural marker of confidence. Collectively, our findings demonstrate for the first time that neural indices of confidence are functionally involved in information-seeking decisions.

Modal Decomposition and Linear Modeling of Swirl Fluctuations in the Mixing Section of a Model Combustor Based on PIV Data

2021 ◽  
Author(s):  
Jens Satria Müller ◽  
Finn Lückoff ◽  
Thomas Ludwig Kaiser ◽  
Christian Oliver Paschereit ◽  
Kilian Oberleithner
Keyword(s):  
Acoustic Waves ◽  
Stokes Equations ◽  
Flow Instability ◽  
Theoretical Work ◽  
Navier Stokes ◽  
Inertial Waves ◽  
Linear Modeling ◽  
Swirl Combustor ◽  
Time Resolved ◽  
Flow Response

Abstract In order to determine the flame transfer function of a combustion system only based on isothermal flow field data, three governing mechanisms have been identified which need to be modeled: swirl fluctuations, equivalence fluctuations and velocity fluctuations excited by planar acoustic waves. This study focuses on the generation and propagation of swirl fluctuations downstream of a radial swirl combustor under isothermal conditions. Swirl fluctuations are generated experimentally by imposing acoustic perturbations. Time-resolved longitudinal and crosswise PIV measurements are conducted inside the mixing tube and combustion chamber to quantify the evolution of the swirl fluctuations. The measured flow response is decomposed using spectral proper orthogonal decomposition to unravel the contributions of different dynamical modes. In addition a resolvent analysis is conducted based on the linearized Navier-Stokes equations to reveal the intrinsically most amplified flow structures. Both, the data-driven and analytic approach, show that inertial waves are indeed present in the flow response and an inherent flow instability downstream of the swirler, which confirms the recent theoretical work of Albayrak et al. (Journal of Fluid Mechanics, 879). However, the contribution of these inertial waves to the total swirl fluctuations turns out to be very small. This is suggested to be due to the very structured forcing at the swirler and the amplification of shear-driven modes which are expected to be much more influential for this type of swirler. Overall, this work confirms the presence of inertial waves in highly turbulent swirl combustors and evaluates its relevance for industry-related configurations. It further outlines a methodology to analyze and predict their characteristics based on mean fields only, which is applicable for complex geometries of industrial relevance.

scholarly journals Laser-Induced Control of the Optical Response of Aluminum Phthalocyanine Chloride Complexes Dissolved in Ethanol

2021 ◽  
Vol 9 ◽  
Author(s):  
Carina da Costa Castanheira ◽  
Andreas Persch ◽  
Paul Birk ◽  
Christian Ott ◽  
Thomas Pfeifer
Keyword(s):  
Excited States ◽  
Time Window ◽  
Intense Laser ◽  
Intense Laser Fields ◽  
Chloride Complexes ◽  
Complex Molecules ◽  
Time Resolved ◽  
Coherent Coupling ◽  
Coupling Dynamics ◽  
And Control

We show that absorption spectra of aluminum chloride phthalocyanine (AlClPc) in the liquid phase can be dynamically modified through the time-resolved interaction with a second laser pulse during a time window on the order of 100 fs. The observed effects can be explained by laser-induced coherent coupling dynamics between the ground state and a bath of excited states as reproduced by a few-level toy model. The presented results help to understand how intense laser fields interact with complex molecules in solution, but in their laser-controlled response still much alike isolated atoms in the gas phase. This understanding can, in the future, be used to modify and control the dynamics in complex systems.

scholarly journals Intrinsic Ferroelectricity in Charge-Ordered Magnetite

Crystals ◽  
2019 ◽  
Vol 9 (11) ◽  
pp. 546
Author(s):  
Manuel Angst ◽  
Shilpa Adiga ◽  
Semen Gorfman ◽  
Michael Ziolkowski ◽  
Jörg Strempfer ◽  
...  
Keyword(s):  
Low Temperatures ◽  
Time Window ◽  
Bragg Reflection ◽  
Relaxor Ferroelectric ◽  
Threshold Field ◽  
Diffraction Experiment ◽  
Time Resolved ◽  
Switchable Polarization ◽  
Ordered State

Single crystalline magnetite Fe 3 O 4 was investigated at low temperatures in the charge ordered state by electric measurements and time-resolved diffraction with voltage applied in-situ. Dielectric spectroscopy indicates relaxor ferroelectric characteristics, with polarization switching observably only at sufficiently low temperatures and in a suitably chosen time-window. PUND measurements with a ms time scale indicate a switchable polarization of about 0 . 6 μ C / cm 2 . Significant switching occurs only above a threshold field of about 3 kV / mm , and it occurs with a time delay of about 20 μ s . The time-resolved diffraction experiment yields, for sufficiently high voltage pulses, a systematic variation by about 0 . 1 % of the intensity of the ( 2 , 2 ¯ , 10 ¯ ) Bragg reflection, which is attributed to structural switching of domains of the non-centrosymmetric C c structure to its inversion twins, providing proof of intrinsic ferroelectricity in charge ordered magnetite.

Time-resolved photoluminescence in CdIn2S4

1987 ◽  
Vol 65 (3) ◽  
pp. 204-207 ◽  
Author(s):  
S. Charbonneau ◽  
E. Fortin ◽  
J. Beauvais
Keyword(s):  
Single Crystals ◽  
Free Electron ◽  
Continuous Wave ◽  
Time Window ◽  
Photoluminescence Spectra ◽  
Time Resolved ◽  
Spectral Bands ◽  
Window Technique ◽  
Donor Acceptor ◽  
Time Resolved Photoluminescence

Photoluminescence spectra of CdIn2S4 single crystals at 1.8 K under both continuous-wave (CW) and pulsed excitation were obtained. In the latter case, a variable time-window technique was used to observe the time evolution of the spectra between 0 and 100 μs. In contrast to previous studies, four spectral bands were observed under both CW and pulsed, intrinsic or extrinsic excitation. In particular, two bands previously unobserved under extrinsic excitation were detected at 1.35 and 1.68 eV, and have been attributed to donor–acceptor pairs and free-electron to acceptor transitions respectively.

scholarly journals People adaptively use information to improve their internal and external states

2021 ◽  
Author(s):  
Irene Cogliati Dezza ◽  
Christina Maher ◽  
Tali Sharot
Keyword(s):  
Information Seeking ◽  
Adaptive Strategy ◽  
Well Being ◽  
Subjective Expectations ◽  
Total N ◽  
Internal States ◽  
Affect And Cognition ◽  
Standard Models ◽  
The Impact ◽  
Better Than

Information can strongly impact peoples’ affect, their level of uncertainty and their decisions. It is assumed that people seek information with the goal of improving all three. But are they successful at achieving this goal? Answering this question is important for assessing the impact of self-driven information consumption on people’s well-being. Here, over four experiments (total N = 518) we show that participants accurately predict the impact of information on their internal states (e.g., affect and cognition) and external outcomes (e.g., material rewards), and use these predictions to guide information-seeking choices. A model incorporating participants’ subjective expectations regarding the impact of information on their affective, cognitive, and material outcomes accounted for information-seeking choices better than standard models currently used in the literature, which include objective proxies of those subjective measures. This model also accounted for individual differences in information-seeking choices. By balancing considerations of the impact of information on affective, cognitive and material outcomes when seeking knowledge, participants became happier, more certain and earned more points when they purchased information relative to when they did not, suggesting they adopted an adaptive strategy.

scholarly journals Spatiospectral brain networks reflective of improvisational experience

2021 ◽  
Author(s):  
Josef Faller ◽  
Andrew Goldman ◽  
Yida Lin ◽  
James R. McIntosh ◽  
Paul Sajda
Keyword(s):  
Large Scale ◽  
Time Window ◽  
Network Connectivity ◽  
Functional Class ◽  
Network Activity ◽  
Oddball Paradigm ◽  
Auditory Oddball ◽  
Scalp Eeg ◽  
Musical Structures ◽  
Functional Classes

AbstractMusical improvisers are trained to categorize certain musical structures into functional classes, which is thought to facilitate improvisation. Using a novel auditory oddball paradigm (Goldman et al., 2020) which enables us to disassociate a deviant (i.e. musical cord inversion) from a consistent functional class, we recorded scalp EEG from a group of musicians who spanned a range of improvisational and classically trained experience. Using a spatiospectral based inter and intra network connectivity analysis, we found that improvisers showed a variety of differences in connectivity within and between large-scale cortical networks compared to classically trained musicians, as a function of deviant type. Inter-network connectivity in the alpha band, for a time window leading up to the behavioural response, was strongly linked to improvisation experience, with the default mode network acting as a hub. Spatiospectral networks post response were substantially different between improvisers and classically trained musicians, with greater inter-network connectivity (specific to the alpha and beta bands) seen in improvisers whereas those with more classical training had largely reduced inter-network activity (mostly in the gamma band). More generally, we interpret our findings in the context of network-level correlates of expectation violation as a function of subject expertise, and we discuss how these may generalize to other and more ecologically valid scenarios.

scholarly journals A Postdecisional Neural Marker of Confidence Predicts Information-Seeking in Decision-Making

2019 ◽  
Vol 39 (17) ◽  
pp. 3309-3319 ◽  
Author(s):  
Kobe Desender ◽  
Peter Murphy ◽  
Annika Boldt ◽  
Tom Verguts ◽  
Nick Yeung
Keyword(s):  
Decision Making ◽  
Information Seeking ◽  
Neural Marker

scholarly journals Alkanes increase the stability of early life membrane models under extreme pressure and temperature conditions

2021 ◽  
Vol 4 (1) ◽  
Author(s):  
Loreto Misuraca ◽  
Bruno Demé ◽  
Philippe Oger ◽  
Judith Peters
Keyword(s):  
Early Life ◽  
Hydrothermal Vents ◽  
Time Window ◽  
Extreme Temperature ◽  
Adaptive Strategy ◽  
Multilamellar Vesicle ◽  
Chain Dynamics ◽  
Terrestrial Life ◽  
Temperature And Pressure ◽  
Membrane Components

AbstractTerrestrial life appeared on our planet within a time window of [4.4–3.5] billion years ago. During that time, it is suggested that the first proto-cellular forms developed in the surrounding of deep-sea hydrothermal vents, oceanic crust fractures that are still present nowadays. However, these environments are characterized by extreme temperature and pressure conditions that question the early membrane compartment’s capability to endure a stable structural state. Recent studies proposed an adaptive strategy employed by present-day extremophiles: the use of apolar molecules as structural membrane components in order to tune the bilayer dynamic response when needed. Here we extend this hypothesis on early life protomembrane models, using linear and branched alkanes as apolar stabilizing molecules of prebiotic relevance. The structural ordering and chain dynamics of these systems have been investigated as a function of temperature and pressure. We found that both types of alkanes studied, even the simplest linear ones, impact highly the multilamellar vesicle ordering and chain dynamics. Our data show that alkane-enriched membranes have a lower multilamellar vesicle swelling induced by the temperature increase and are significantly less affected by pressure variation as compared to alkane-free samples, suggesting a possible survival strategy for the first living forms.

scholarly journals Data-driven modeling reveals the Western dominance of global public interest in earthquakes

2021 ◽  
Vol 8 (1) ◽  
Author(s):  
Jonghun Kam ◽  
Jihun Park ◽  
Wanyun Shao ◽  
Junho Song ◽  
Jinhee Kim ◽  
...  
Keyword(s):  
Big Data ◽  
Public Interest ◽  
Information Seeking ◽  
Time Window ◽  
Time Windows ◽  
Developed Countries ◽  
Humanitarian Organizations ◽  
Policy Interventions ◽  
Data Driven Modeling ◽  
Information Seeking Behaviors

AbstractCatastrophic earthquakes stimulate information-seeking behaviors beyond the affected geographical boundaries; however, our understanding of the dynamics of global public interest in earthquakes remains limited. Herein, we harness Big Data to examine the dynamic patterns of global public interest, concerning 17 significant worldwide earthquakes over 2004–2019. We find that the global community shows a higher level of interest when an earthquake occurs in developed countries than in developing countries; however, they lose their interest in the former more rapidly than the latter. Regardless of the affected nation, there is a one- to two-week “golden” time window when attention can be leveraged for fundraising and humanitarian aid. Our findings suggest that European citizens who are highly interested in earthquakes emerge as a potential key community to achieve great inclusiveness in policy interventions to solicit international aid. The findings of this study hint at how Big Data can be utilized to identify “time windows of opportunities” for international humanitarian organizations to efficiently raise donations, charities, and aid resources around the world.

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