Learning the meaning of new stimuli increases the cross-correlated activity of prefrontal neurons

The prefrontal cortex (PF) has a key role in learning rules and generating associations between stimuli and responses also called conditional motor learning. Previous studies in PF have examined conditional motor learning at the single cell level but not the correlation of discharges between neurons at the ensemble level. In the present study, we recorded from two rhesus monkeys in the dorsolateral and the mediolateral parts of the prefrontal cortex to address the role of correlated firing of simultaneously recorded pairs during conditional motor learning. We trained two rhesus monkeys to associate three stimuli with three response targets, such that each stimulus was mapped to only one response. We recorded the neuronal activity of the same neuron pairs during learning of new associations and with already learned associations. In these tasks after a period of fixation, a visual instruction stimulus appeared centrally and three potential response targets appeared in three positions: right, left, and up from center. We found a higher number of neuron pairs significantly correlated and higher cross-correlation coefficients during stimulus presentation in the new than in the familiar mapping task. These results demonstrate that learning affects the PF neural correlation structure

The infernal link: democratic conditionality and State debt to International Organisms

Developing States have contracted many debts, especially since the early 1980s, with creditors. These can be either States or international financial institutions. However, whoever the public debtor is, the latter will intervene more or less directly, increasingly becoming an interlocutor in any attempt to renegotiate or even totally pay the debt itself. This ubiquity arises many questions about its purpose and nature. This is particularly true of the political regimes of indebted states. Indeed, the democratization of these states has become both a means and an end for financial institutions, as the Initiative for Heavily Indebted Poor Countries. Therefore, the question is whether the payment is possible or an illusion

role of the social actor during social interaction and learning in human monkey paradigms

Abstract The social interactions between primates is drawn by their ability to predict others' behaviours, to learn from others' actions and to represent others' intentions. It allows them to extract information by observation to understand which action is leading to which outcome and to maximize the efficiency of their own future behaviours. These processes have mainly been investigated studying non-human primates observing conspecifics, but more recently an increasing body of work has adopted a human-monkey paradigm, and some have now convincingly shown that macaque monkeys understand human choices, consider them and can act accordingly. Two main hypotheses have been developed to explain macaque monkeys' ability to learn from humans: 1) the similarity between the behaviours of both species 2) the presence of a non-ambiguous link between the observed action and its outcome. Based on the literature examined the recent evidence appears to supports the second. The non-social observational learning, meaning the learning by observation of an inanimate agent, can be a powerful tool to understand the mechanisms underlying the social interactions

La céramique Lalonde High Collar comme outil de recherche pour l'étude des échanges dans le Nord-Est de l'Amérique du Nord (1450-1550 A.D.)

Cette thèse de doctorat a pour sujet de recherche, le Lalonde High Collar, une étude céramique qui porte principalement sur l’emploi que l’on peut faire de ce matériel archéologique comme source d’informations dans la thématique des échanges. Notre matériel de travail est une céramique nommée Lalonde High Collar. Facilement identifiable et en quantité relativement importante, elle servira de base pour tester, dans le cadre d’une étude de caractérisation et de provenance, le croisement des regards archéo-ethnographiques, archéologiques ou archéométriques, et différentes méthodes d’analyses physico-chimiques par activation neutronique, microscopie optique et microscopie électronique à balayage. Cette céramique illustre un phénomène de diffusion matérielle à grande échelle. On peut retrouver ce type Lalonde High Collar en bordure du lac Huron, dans la région du lac Saint-Jean, et jusque sur des sites de l’Etat de New York. La grande répartition de ce type pose alors la question du mode de diffusion de cette poterie et, plus généralement, celle de la forme des échanges dans le Nord-Est nord américain. Dans cette perspective, il s’agira donc de mettre en place, à partir de cette céramique, une méthodologie de recherche pour les échanges amérindiens des périodes préhistoriques, en vue de palier au manque de sources écrites

Marie-Antoinette dans les fonds des archives nationales

Pendant plus de vingt ans, Marie-Antoinette a été sur le devant de la scène historique française et depuis deux siècles elle ne cesse de susciter des études historiques ou des biographies romancées et d’intéresser, sinon de fasciner, par son destin exceptionnel. Pour tous les auteurs de ces travaux, le recours aux Archives nationales est incontournable. Pourtant, à y regarder de plus près, il n’existe pas aux Archives nationales de fonds Marie-Antoinette, c’est-à-dire d’ensemble constitué et ..

Effects of reward size and context on learning in macaque monkeys

Abstract The outcome of an action plays a crucial role in decision-making and reinforcement learning processes. Indeed, both human and animal behavioural studies have shown that different expected reward values, either quantitatively or qualitatively, modulate the motivation of subjects to perform an action and, as a consequence, affect their behavioural performance. Here, we investigated the effect of different amounts of reward on the learning of macaque monkeys using a modified version of the object-in-place task. This task offers the opportunity to shape rapid learning based on a set of external stimuli that enhance an animal's accuracy in terms of solving a problem. We compared the learning of three monkeys among three different reward conditions. Our results demonstrate that the larger the reward, the better the monkey's ability to learn the associations starting with the second presentation of the problem. Moreover, we compared the present results with those of our previous work using the same monkeys in the same task but with a unique reward condition, the intermediate one. Interestingly, the performance of our animals in our previous work matched with their performance in the largest and not intermediate reward condition of the present study These results suggest that learning is mostly influenced by the reward context and not by its absolute value

Outcome modulation across tasks in the primate dorsolateral prefrontal cortex

Animals need to learn and to adapt to new and changing environments so that appropriate actions that lead to desirable outcomes are acquired within each context. The prefrontal cortex (PF) is known to underlie such function that directly implies that the outcome of each response must be represented in the brain for behavioral policies update. However, whether such PF signal is context dependent or it is a general representation beyond the specificity of a context is still unclear. Here, we analyzed the activity of neurons in the dorsolateral PF (PFdl) recorded while two monkeys performed two perceptual magnitude discrimination tasks. Both tasks were well known by the monkeys and unexpected changes did not occur but the difficulty of the task varied from trial to trial and thus the monkeys made mistakes in a proportion of trials. We show a context-independent coding of the response outcome with neurons maintaining similar selectivity in both task contexts. Using a classification method of the neural activity, we also show that the trial outcome could be well predicted from the activity of the same neurons in the two contexts. Altogether, our results provide evidence of high degree of outcome generality in PFdl

La liaison infernale: conditionnalité démocratique et dette des Etats à l’égard des organisations internationales

Les Etats en développement ont consenti de nombreuses dettes, surtout depuis le début des années 1980, à l’égard des créanciers publics. Ceuxci peuvent être soit des Etats soit des Institutions Financières Internationales. Cela étant, quelque soit ce débiteur public, ces dernières vont intervenir de manière plus ou moins directe, en devenant progressivement des interlocuteurs incontournables de toute tentative de renégociation, voire d’annulation de la dite dette. Cette omniprésence n’est pas sans susciter de nombreuses interrogations quant à son objet et sa nature. C’est particulièrement le cas de la nature politique des régimes des Etats endettés. En effet, la démocratisation de ces Etats est devenue, de manière discutable, à la fois un moyen et une finalité de l’intervention des Institutions Financières, comme le montre l’Initiative Pour les Pays Pauvres Très Endettés. Dès lors, la question est de savoir si l’annulation totale est envisageable ou une chimère? DOI: http://dx.doi.org/10.22518/16578953.73

Une stratégie nationale pour la collecte et l\u27accès aux archives publiques à l\u27ère numérique

La ministre de la culture et de la communication a confié en 2016 à Christine Nougaret, vice-présidente du Conseil supérieur des Archives, une mission de réflexion sur la collecte des archives à l\u27ère numérique et leur communication aux publics. Elle lui avait notamment demandé de s\u27interroger sur les méthodes et conditions d\u27évaluation et de sélection des archives électroniques, mais aussi papier, et de proposer une stratégie nationale pour l\u27accès aux archives dans l\u27environnement numérique. Les recommandations formulées par Christine Nougaret concernent à la fois les archives nationales et territoriales, le cadre juridique et les pratiques archivistiques, le numérique et l\u27analogique