scholarly journals Synchronization and Redundancy: Implications for Robustness of Neural Learning and Decision Making

2011 ◽  
Vol 23 (11) ◽  
pp. 2915-2941 ◽  
Author(s):  
Jake Bouvrie ◽  
Jean-Jacques Slotine
Keyword(s):  
Decision Making ◽  
Building Blocks ◽  
Decision Function ◽  
Neural Systems ◽  
Cortical Circuits ◽  
Neural Learning ◽  
The Impact ◽  
The Brain ◽  
Source Of Error

Learning and decision making in the brain are key processes critical to survival, and yet are processes implemented by nonideal biological building blocks that can impose significant error. We explore quantitatively how the brain might cope with this inherent source of error by taking advantage of two ubiquitous mechanisms, redundancy and synchronization. In particular we consider a neural process whose goal is to learn a decision function by implementing a nonlinear gradient dynamics. The dynamics, however, are assumed to be corrupted by perturbations modeling the error, which might be incurred due to limitations of the biology, intrinsic neuronal noise, and imperfect measurements. We show that error, and the associated uncertainty surrounding a learned solution, can be controlled in large part by trading off synchronization strength among multiple redundant neural systems against the noise amplitude. The impact of the coupling between such redundant systems is quantified by the spectrum of the network Laplacian, and we discuss the role of network topology in synchronization and in reducing the effect of noise. We discuss range of situations in which the mechanisms we model arise in brain science and draw attention to experimental evidence suggesting that cortical circuits capable of implementing the computations of interest here can be found on several scales. Finally, simulations comparing theoretical bounds to the relevant empirical quantities show that the theoretical estimates we derive can be tight.

scholarly journals Online Reviews and Product Sales: The Role of Review Visibility

2021 ◽  
Vol 16 (4) ◽  
pp. 638-669
Author(s):  
Miriam Alzate ◽  
Marta Arce-Urriza ◽  
Javier Cebollada
Keyword(s):  
Decision Making ◽  
Dynamic Models ◽  
Generalized Method Of Moments ◽  
Online Reviews ◽  
Consumer Decision Making ◽  
Product Sales ◽  
The Impact ◽  
The Relationship ◽  
The Empirical Analysis

When studying the impact of online reviews on product sales, previous scholars have usually assumed that every review for a product has the same probability of being viewed by consumers. However, decision-making and information processing theories underline that the accessibility of information plays a role in consumer decision-making. We incorporate the notion of review visibility to study the relationship between online reviews and product sales, which is proxied by sales rank information, studying three different cases: (1) when every online review is assumed to have the same probability of being viewed; (2) when we assume that consumers sort online reviews by the most helpful mechanism; and (3) when we assume that consumers sort online reviews by the most recent mechanism. Review non-textual and textual variables are analyzed. The empirical analysis is conducted using a panel of 119 cosmetic products over a period of nine weeks. Using the system generalized method of moments (system GMM) method for dynamic models of panel data, our findings reveal that review variables influence product sales, but the magnitude, and even the direction of the effect, vary amongst visibility cases. Overall, the characteristics of the most helpful reviews have a higher impact on sales.

scholarly journals Consciousness, decision making, and volition: freedom beyond chance and necessity

2021 ◽  
Author(s):  
Hans Liljenström
Keyword(s):  
Decision Making ◽  
Free Will ◽  
Brain Activity ◽  
Brain Structures ◽  
Complex Process ◽  
Neural Information ◽  
Neural Information Processing ◽  
Stochastic Population Model ◽  
The Brain

AbstractWhat is the role of consciousness in volition and decision-making? Are our actions fully determined by brain activity preceding our decisions to act, or can consciousness instead affect the brain activity leading to action? This has been much debated in philosophy, but also in science since the famous experiments by Libet in the 1980s, where the current most common interpretation is that conscious free will is an illusion. It seems that the brain knows, up to several seconds in advance what “you” decide to do. These studies have, however, been criticized, and alternative interpretations of the experiments can be given, some of which are discussed in this paper. In an attempt to elucidate the processes involved in decision-making (DM), as an essential part of volition, we have developed a computational model of relevant brain structures and their neurodynamics. While DM is a complex process, we have particularly focused on the amygdala and orbitofrontal cortex (OFC) for its emotional, and the lateral prefrontal cortex (LPFC) for its cognitive aspects. In this paper, we present a stochastic population model representing the neural information processing of DM. Simulation results seem to confirm the notion that if decisions have to be made fast, emotional processes and aspects dominate, while rational processes are more time consuming and may result in a delayed decision. Finally, some limitations of current science and computational modeling will be discussed, hinting at a future development of science, where consciousness and free will may add to chance and necessity as explanation for what happens in the world.

Preserving Integrity in the Face of Performance Threat

2012 ◽  
Vol 23 (12) ◽  
pp. 1455-1460 ◽  
Author(s):  
Lisa Legault ◽  
Timour Al-Khindi ◽  
Michael Inzlicht
Keyword(s):  
Error Detection ◽  
Error Monitoring ◽  
Error Related Negativity ◽  
Threatening Information ◽  
Electrophysiological Responses ◽  
The Face ◽  
And Performance ◽  
The Impact ◽  
The Brain

Self-affirmation produces large effects: Even a simple reminder of one’s core values reduces defensiveness against threatening information. But how, exactly, does self-affirmation work? We explored this question by examining the impact of self-affirmation on neurophysiological responses to threatening events. We hypothesized that because self-affirmation increases openness to threat and enhances approachability of unfavorable feedback, it should augment attention and emotional receptivity to performance errors. We further hypothesized that this augmentation could be assessed directly, at the level of the brain. We measured self-affirmed and nonaffirmed participants’ electrophysiological responses to making errors on a task. As we anticipated, self-affirmation elicited greater error responsiveness than did nonaffirmation, as indexed by the error-related negativity, a neural signal of error monitoring. Self-affirmed participants also performed better on the task than did nonaffirmed participants. We offer novel brain evidence that self-affirmation increases openness to threat and discuss the role of error detection in the link between self-affirmation and performance.

Ties that Bind?

1998 ◽  
Vol 31 (1) ◽  
pp. 45-71 ◽  
Author(s):  
WILL H. MOORE ◽  
DAVID R. DAVIS
Keyword(s):  
Decision Making ◽  
Statistical Analysis ◽  
General Model ◽  
International Conflict ◽  
Conflict Behavior ◽  
Structural Constraints ◽  
Structural Factors ◽  
International Interactions ◽  
The Impact

In this article, the authors develop and empirically evaluate a general model of the linkages between domestic and international conflict behavior. Much of the literature on domestic international interactions has focused on the structural constraints of the international and domestic systems on leaders' foreign policy decisions. Rather than focusing on structural constraints, the present authors model the influence of the behavior of domestic and international rivals on leader decision making. The impact of rivals' behavior on conflict across the domestic-international nexus has been neglected relative to the role of structural factors. This study helps redress that imbalance. The authors test their model with a statistical analysis of Zaire during the period 1975 to 1992 and find substantial support for the model.

scholarly journals Research participants as collaborators: Background, experience and policies from the PREVENT Dementia and EPAD programmes

Dementia ◽  
2018 ◽  
Vol 17 (8) ◽  
pp. 1045-1054 ◽  
Author(s):  
Sarah Gregory ◽  
Katie Wells ◽  
Kate Forsyth ◽  
Cate Latto ◽  
Helen Szyra ◽  
...  
Keyword(s):  
Patient Involvement ◽  
Research Participant ◽  
Steering Committee ◽  
Research Participants ◽  
Prospective Cohort Studies ◽  
Participant Experience ◽  
The Impact ◽  
The Brain ◽  
Public And Patient Involvement

Aim Despite the growing importance of public and patient involvement in biomedical research, comparatively little attention has been paid to the important role of research participants themselves. Our aim in this paper is to explore the impact research participant involvement has within the PREVENT and the European Prevention of Alzheimer’s Dementia (EPAD) projects. Method In this paper, we report the experiences of involving research participants as collaborators in prospective cohort studies exploring early changes in the brain as pathways towards and risks for dementia. We use minutes and feedback from members of the panel and steering committee to understand the experience and impact on the study. Results We describe the aims and structure of the participant panel established within the PREVENT Dementia study and highlight its contributions to the organisation, conduct and future of the study. Key areas of contribution identified include recruitment, inclusion of additional sub-studies, understanding the participant experience and contributing to the future of the study. Discussion We then describe how the PREVENT Dementia panel forms the basis for participant involvement within EPAD project.

scholarly journals Is There a Link between Oropharyngeal Microbiome and Schizophrenia? A Narrative Review

2022 ◽  
Vol 23 (2) ◽  
pp. 846
Author(s):  
Stanislas Martin ◽  
Audrey Foulon ◽  
Wissam El Hage ◽  
Diane Dufour-Rainfray ◽  
Frédéric Denis
Keyword(s):  
Periodontal Disease ◽  
Research Team ◽  
Oral Microbiome ◽  
Oral Microbiota ◽  
Future Studies ◽  
The Subject ◽  
The Moment ◽  
The Impact ◽  
The Brain

The study aimed to examine the impact of the oropharyngeal microbiome in the pathophysiology of schizophrenia and to clarify whether there might be a bidirectional link between the oral microbiota and the brain in a context of dysbiosis-related neuroinflammation. We selected nine articles including three systemic reviews with several articles from the same research team. Different themes emerged, which we grouped into 5 distinct parts concerning the oropharyngeal phageome, the oropharyngeal microbiome, the salivary microbiome and periodontal disease potentially associated with schizophrenia, and the impact of drugs on the microbiome and schizophrenia. We pointed out the presence of phageoma in patients suffering from schizophrenia and that periodontal disease reinforces the role of inflammation in the pathophysiology of schizophrenia. Moreover, saliva could be an interesting substrate to characterize the different stages of schizophrenia. However, the few studies we have on the subject are limited in scope, and some of them are the work of a single team. At this stage of knowledge, it is difficult to conclude on the existence of a bidirectional link between the brain and the oral microbiome. Future studies on the subject will clarify these questions that for the moment remain unresolved.

scholarly journals A selective effect of dopamine on information-seeking

eLife ◽  
2020 ◽  
Vol 9 ◽  
Author(s):  
Valentina Vellani ◽  
Lianne P de Vries ◽  
Anne Gaule ◽  
Tali Sharot
Keyword(s):  
Parkinson’S Disease ◽  
Parkinson's Disease ◽  
Information Seeking ◽  
Selective Effect ◽  
Reward Seeking ◽  
The Impact ◽  
The Brain ◽  
Insight Into ◽  
Primary Reward

Humans are motivated to seek information from their environment. How the brain motivates this behavior is unknown. One speculation is that the brain employs neuromodulatory systems implicated in primary reward-seeking, in particular dopamine, to instruct information-seeking. However, there has been no causal test for the role of dopamine in information-seeking. Here, we show that administration of a drug that enhances dopamine function (dihydroxy-L-phenylalanine; L-DOPA) reduces the impact of valence on information-seeking. Specifically, while participants under Placebo sought more information about potential gains than losses, under L-DOPA this difference was not observed. The results provide new insight into the neurobiology of information-seeking and generates the prediction that abnormal dopaminergic function (such as in Parkinson’s disease) will result in valence-dependent changes to information-seeking.

scholarly journals Role of the Global Fund in national HIV/AIDS response in Myanmar: a qualitative study

2021 ◽  
Vol 6 (1) ◽  
Author(s):  
Zarni Htun ◽  
Yingxi Zhao ◽  
Hannah Gilbert ◽  
Chunling Lu
Keyword(s):  
Civil Society ◽  
Qualitative Study ◽  
Health System ◽  
Global Fund ◽  
Scale Up ◽  
Building Blocks ◽  
Key Informants ◽  
The Impact ◽  
Hiv Aids

Abstract Background The Global Fund has been a major funding source for HIV/AIDS programs in Myanmar. In this qualitative study, we aim to understand the impact of Global Fund on national HIV/AIDS response in Myanmar during the era of Millennium Development Goals (MDGs). Methods We conducted individual in-depth interviews by recruiting key informants through purposive snowball sampling. The respondents were engaged in the national/subnational response to HIV/AIDS in Myanmar and worked for the United Nations agencies, non-governmental organizations (NGOs), and civil society. Interview questions were organized around the role of Global Fund in strengthening national response to HIV/AIDS in the six building blocks of the Myanmar’s health system. Transcripts from the key informants were synthesized into specific themes through a deductive approach. Results We found that the Global Fund has provided substantial support to (1) finance the national HIV/AIDS response in Myanmar, and (2) strengthen leadership and governance at the central level through improving coordination and collaboration, including more stakeholders (e.g. civil society, NGOs) in decision making process, and catalyzing policy changes on scaling-up key interventions. Yet, its role remains limited in addressing new demands at the township level in terms of capacity building, staffing, and medical supply resulting from rapid scale-up of HIV interventions and decentralization of service delivery in the public sector. Conclusion There was a missed opportunity for Myanmar to capitalize on the use of the Global Fund’s funding to strengthen the health system. Deliberate planning is required to optimize the use of those scarce resources to provide universal coverage for HIV/AIDS.

scholarly journals Impact of Behavioral Biases on Investment Decision Making with Moderating Role of Financial Literacy

2018 ◽  
Vol 6 (2) ◽  
pp. 34-41
Author(s):  
Rizwan Khalid ◽  
◽  
Muhammad Javed ◽  
Khurram Shahzad ◽  
◽  
...  
Keyword(s):  
Decision Making ◽  
Financial Literacy ◽  
Positive Impact ◽  
Investment Decision ◽  
Structure Questionnaire ◽  
Investment Decision Making ◽  
Overconfidence Bias ◽  
The Impact ◽  
Moderating Role

The objective of this study is to examine the Impact of Overconfidence bias and Herding bias on Investment Decision Making with Moderating Role of Financial Literacy. The population was Investor, Employee and Graduate Student. A sample of 200 was selected using convenience technique. Data were collected through structure questionnaire adopted from different papers. Correlation and Regression analysis were performed to examine the result. The Results show that overconfidence bias and herding bias have a positive impact on investment decision making and Financial Literacy has positive impact on investment decision making. Based on the results and discussions of the study findings as well as the limitations, theoretical and practical implications of the study have been provided.

scholarly journals THE IMPACT OF CONTROL PROCESSES ON MANAGERIAL DECISION MAKING

2012 ◽  
Vol 3 (1) ◽  
pp. 43-52
Author(s):  
Jan Kráčmar ◽  
Miroslav Uhliar
Keyword(s):  
Decision Making ◽  
Control Function ◽  
Decision Function ◽  
Managerial Control ◽  
Managerial Decision ◽  
Managerial Work ◽  
Managerial Decision Making ◽  
Positive Effects ◽  
Control Processes ◽  
The Impact

Control and managerial decision function activities have an important share in the managerial work. The paper The Impact of Control Processes on Managerial Decision Making describes the share of managerial control and decision function on the total managerial work. It also evaluates the influence of control activities on the decision making functions of different -level managers in questioned companies doing business in Slovak Republic. The results were obtained thanks to the surveying method. 392 participants took part in the research, which was made in two phases (in 2008 and 2010). The findings show the importance of managerial functions of control and decision making. They identify over 21% of control function- and almost 30% of decision making function share on total managerial work. There were discovered, many positive effects of control function on managerial decision making, while only few and insignificant negatives were identified. Key words: manager, control function, managerial decision making, evaluation, manager job content.

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