Executive control: balancing stability and flexibility via the duality of evolutionary neuroanatomical trends

The concept of executive functions has a rich history and remains current despite increased use of other terms, including working memory and cognitive control. Executive functions have sometimes been equated with functions subserved by the frontal cortex, but this adds little clarity, given that we so far lack a comprehensive theory of frontal function. Pending a more complete mechanistic understanding, clinically useful generalizations can help characterize both healthy cognition and multiple varieties of cognitive impairment. This article surveys several hierarchical and autoregulatory control theories, and suggests that the evolutionary cytoarchitectonic trends theory provides a valuable neuroanatomical framework to help organize research on frontal structure-function relations. The theory suggests that paleocortical/ventrolateral and archicortical/dorsomedial trends are associated with neural network flexibility and stability respectively, which comports well with multiple other conceptual distinctions that have been proposed to characterize ventral and dorsal frontal functions, including the “initiation/inhibition,” “what/where,” and “classification/expectation” hypotheses

A System-Level Model of Noradrenergic Function

International audienceNeuromodulation is an interesting way to display different modes of functioning in a complex network. The effect of Noradrenaline has often been related to the exploration/exploitation trade-off and implemented in models by modulation of the gain of activation function. In this paper, we show that this mechanism is not sufficient for system-level networks and propose another way to implement it, exploiting reported inhibition of a striatal region by Noradrenaline. We describe here the corresponding model and report its performances in a reversal task

Modeling Neuromodulation as a Framework to Integrate Uncertainty in General Cognitive Architectures

International audienceOne of the most critical properties of a versatile intelligent agent is its capacity to adapt autonomously to any change in the environment without overly complexifying its cognitive architecture. In this paper, we propose that understanding the role of neuromodulation in the brain is of central interest for this purpose. More precisely, we propose that an accurate estimation of the nature of uncertainty present in the environment is performed by specific brain regions and broadcast throughout the cerebral network by neuromodulators, resulting in appropriate changes in cerebral functioning and learning modes. Better understanding the principles of these mechanisms in the brain might tremendously inspire the field of Artificial General Intelligence. The original contribution of this paper is to relate the four major neuromodulators to four fundamental dimensions of uncertainty

Modeling the sensory roles of noradrenaline in action selection

International audienceNoradrenaline participates in the neuromodulation of brain activity to modify the trade-off between exploration and exploitation when sensory contingencies have changed. Accordingly, attentional models of noradrenaline acting on sensory representations have been proposed. In this paper , we explore another possible action of this neuromodulator in the decision making process and report simulation results that illustrate that its role is concerned with different aspects of sensory processing. This is made possible by the extension of a classical model of action selection, to render it able to detect and to adapt to sudden changes in sensory contingencies, which is a major characteristic of autonomous learning

Positive and Negative Congruency Effects in Masked Priming: A Neuro-computational Model Based on Representation Strength and Attention

Positive priming effects have been found with a short time between the prime and the target, while negative priming effects (i.e., a congruent prime causes longer RTs) have been found with a long time between the prime and the target. In the current study, positive and negative priming effects were found using stimuli that have strong and weak representations, respectively, without changing the time between prime and target. A model was developed that fits our results. The model also fits a wide range of previous results in this area. In contrast to other approaches our model depends on attentional neuro-modulation not motor self-inhibition

Using Biomedical Technologies to Inform Economic Modeling: Challenges and Opportunities for Improving Analysis of Environmental Policies

Advances in biomedical technology have irrevocably jarred open the black box of human decision making, offering social scientists the potential to validate, reject, refine and redefine the individual models of resource allocation that form the foundation of modern economics. In this paper we (1) provide a comprehensive overview of the biomedical methods that may be harnessed by economists and other social scientists to better understand the economic decision making process; (2) review research that utilizes these biomedical methods to illuminate fundamental aspects of the decision making process; and (3) summarize evidence from this literature concerning the basic tenants of neoclassical utility that are often invoked for positive welfare analysis of environmental policies. We conclude by raising questions about the future path of policy related research and the role biomedical technologies will play in defining that path.neuroeconomics, neuroscience, brain imaging, genetics, welfare economics, utility theory, biology, decision making, preferences, Institutional and Behavioral Economics, Research Methods/ Statistical Methods, D01, D03, D6, D87,

A behavioral framework for information representation in the brain

International audienceAlong evolution, increasingly complex cognitive functions have been attributed to an increasingly complex brain architecture. Nevertheless, the brain remains anchored on an organization dedicated to survival. We believe that keeping this principle in mind is an excellent way to better decipher cerebral mechanisms and corresponding cognitive functions. Accordingly, we describe here the main characteristics and constraints of an intelligent agent learning to survive in an intelligent environment, in terms of information flows and learning principles. On this basis, we propose a framework of description for the architecture of the brain of mammals, organized around four fundamental questions to be answered. These questions define the identity of the goal (what ?) and the motivation to choose it (why ?), its location (where ?) and the way to get it (how ?). Then we explain how the main requirements of respondent and operant conditioning can be addressed within this architecture and how it is also compatible with the elaboration of more complex cognitive mechanisms. This can be seen as the validation of this framework to explore how cognitive functions might emerge from cerebral circuits and how they have been made more complex along evolution. It also proposes a systemic view of the brain, useful to develop the cogni-tive architecture of an intelligent agent exploring autonomously its environment and to propose to machine learning innovative algorithms

Psychological capital and contextual ambidexterity: The role of transformational leadership as a moderator

88 pagesTo sustain organizational performance, achieving exploitation in the current operations with the use of already-existing resources and seeking new opportunities and craving for radical changes in a balanced manner is a prominent managerial challenge in today’s competitive business world. Under these circumstances, it is mainly leaders’ role to foster employees’ psychological capital in gaining the autonomy to allocate their time between activities serving to either incremental or revolutionary change. In this sense, considering that contextual ambidexterity is underresearched among other types of organizational ambidexterity, this study contributes to the literature by focusing on psychological capital (PsyCap), of which four dimensions are self-efficacy, hope, resilience and optimism, as one of the antecedents of contextual ambidexterity with the moderation effect of transformational leadership. Using a sample of 181 white-collar employees, upon analyzing the relationships between PsyCap, self-efficacy, hope, resilience and optimism as separate independent variables and contextual ambidexterity as the dependent variable, all of them had positive correlations with one another and regression analyses supported the hypotheses, in the scope of this study, the moderation effect of transformational leadership on these relationships was examined. Hypotheses suggesting that the effect of transformational leadership as a moderator on the relationship between PsyCap, self-efficacy, hope, resilience and hope as independent variables and contextual ambidexterity as the dependent variable in different models in a way that effect of increase in transformational leadership would be positive were not supported.Örgütsel performansı sürdürmede, mevcut operasyonlarda hâlihazırda sahip olunan kaynaklardan faydalanırken yeni fırsatlar arama ve radikal değişiklik arzusunu sürdürmeyi dengeleme günümüz rekabetçi iş yaşamında önemli yönetimsel zorluklardan biridir. Bu koşullar altında, çalışanların vaktini mevcut işler ve yeni fırsatlar yakalama arasında dengeli bölmeleri için gerekli özerkliği kazanmasını sağlamak adına psikolojik sermayelerini güçlendirme sorumluluğu büyük oranda liderlerin görevidir. Bu kapsamda, bağlamsal çift yönlülüğün diğer örgütsel çift yönlülük türleri arasında en az araştırılan olduğu göz önünde bulundurularak, bu çalışma literatüre bağlamsal çift yönlülüğün öncüllerinden biri olarak öz yeterlilik, umut, dayanıklılık ve iyimserlik dört alt boyutu olan psikolojik sermayeye, dönüşümcü liderlik moderasyon etkisiyle odaklanarak katkı sağlamaktadır. 181 kişilik bir beyaz yaka örneklemi kullanarak psikolojik sermaye, öz yeterlilik, umut, iyimserlik ve dayanıklılığı bağımsız değişken ve bağlamsal çift yönlülüğü bağımlı değişken olarak inceleyip değişkenler arasında yüksek korelasyon bulduktan sonra; çalışma kapsamında, bu ilişkilere dönüşümcü liderliğin moderasyon etkisi incelenmektedir. Psikolojik sermaye, öz yeterlilik, dayanıklılık, umut ve iyimserliğin bağımsız değişken ve bağlamsal çift yönlülüğün bağımlı değişken olduğu farklı modellerde, moderatör değişken olarak dönüşümcü liderlikteki artışın modele pozitif etkisi olacağı araştırma hipotezleri bu çalışma kapsamında desteklenmemektedir

Arousal, exploration and the locus coeruleus-norepinephrine system

The studies described in this thesis address a range of topics related to arousal, exploration, temporal attention, and the locus coeruleus-norepinephrine (LC-NE) system. Chapters 2 and 3 report two studies that investigated a recent theory about the role of the LC-NE system in the regulation of the exploration-exploitation trade-off. Chapter 4 reports a study on neurocognitive function in patients with dopamine-β-hydroxylase (DβH) deficiency. Chapter 5 reports an fMRI study on the neural correlates of perceptual curiosity. Chapter 6 and 7 reported several experiments investigating the effects of ‘accessory stimuli’ and temporal certainty on information processing, using scalp electrophysiology and sequential-sampling models of decision making. Taken together, the studies reported in this thesis suggest that arousal, exploration and temporal attention are closely related, which is likely due to a shared neural basis.LEI Universiteit LeidenFSW - Action Control - Ou

Endocannabinoid System in a Planarian Model

In this study, the presence and possible function of endocannabinoid ligands in the planarian is investigated. The endocannabinoids ananadamide (AEA) and 2-arachidonoylglycerol (2-AG) and entourage NAE compounds palmitoylethanolamide (PEA), stearoylethanolamide (SEA) and oleoylethanolamide (OEA) were found in Dugesia dorotocephala. Changes in SEA, PEA, and AEA levels were observed over the initial twelve hours of active regeneration. Exogenously applied AEA, 2-AG and their catabolic inhibition effected biphasic changes in locomotor velocity, analogous to those observed in murines. The genome of a close relative, Schmidtea mediterranea, courtesy of the University of Utah S. med genome database, was explored for cannabinoid receptors, none were found. A putative fatty acid amide hydrolase (FAAH) homolog was found in Schmidtea mediterranea