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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
61

L'espace péripersonnel : un espace pour inter-agir / The peripersonal space : a space to inter-act

Patanè, Ivan 26 April 2018 (has links)
L'espace entourant notre corps est d'une importance vitale: nous surveillons attentivement les objets (animés et inanimés) qui entrent dans les limites de l'espace à immédiate proximité du corps pour interagir avec eux. Dans le domaine des neurosciences cognitives, cet espace est exemplifié par le concept d'espace péripersonnel (PPS), une représentation hautement plastique qui intègre des stimuli tactiles et visuels présentés sur et près du corps. Cette représentation semble contribuer au guidage efficace des actions, cependant dans la littérature on ne retrouve aucune preuve substantielle de l'implication du PPS dans le contrôle des actions. Un argument en faveurs de cette hypothèse dériverait de la preuve que la plasticité du PPS peut effectivement survenir avant le début du mouvement, plutôt que pendant le mouvement. Les résultats de la première étude (chapitre II) révèlent que les informations visuelles et tactiles interagissent de manière significative déjà au cours de la phase de planification de l'action et que cette interaction visuo-tactile augmente ultérieurement au cours des étapes successives du mouvement. Un tel processus de « remappage » visuo-tactile du PPS, qui précède temporellement et accompagne par la suite l'exécution de l'action motrice, semble donc idéalement adapté à pour aider au guidage de nos actions. Récemment, il a été suggéré que le PPS pourrait jouer un rôle dans le guidage des interactions motrices entre individus. En psychologie sociale, l'espace autour du corps est appelé espace interpersonnel (IPS), défini comme l'espace que les individus maintiennent autour d'eux et dans lequel les autres ne peuvent pas pénétrer sans susciter d'inconfort. En raison de certaines similitudes entre les représentions du PPS et du IPS, certains auteurs ont soulevé la question d'un éventuel partage de certaines caractéristiques fonctionnelles entre ces deux représentations. Le deuxième objectif de ma thèse etait de tester cette hypothèse en exploitant un autre processus de «remappage» plastique du PPS, c'est-à-dire celui induit par l'utilisation d'un outil. Les résultats de la deuxième étude (chapitre IV) montrent que l'utilisation «standard» d'un outil «allonge» le PPS, mesuré par la distance d'atteignabilité d'une autre personne, mais n'influence pas l'IPS, mesuré par la distance de confort envers la même personne. Dans la troisième étude (chapitre V), nous avons introduit une nouvelle variante plus sociale de l'utilisation d'un outil pour examiner la plasticité sensorimotrice et sociale des deux espaces. Les résultats obtenus révèlent que l'utilisation sociale d'un outil «allonge» le PPS et en même temps «réduit» l'IPS. La démonstration que l'on peut induire des changements directionnellement opposés entre les deux représentations, falsifie l'hypothèse selon laquelle il peut y avoir un chevauchement fonctionnel entre PPS et IPS. Ces exemples de dissociation fonctionnelle peuvent donc servir à éviter une association inappropriée entre les deux concepts. Si l'hypothèse de l'identité fonctionnelle avec l'IPS ne semble pas légitime, il n'en demeure pas moins que le PPS est également sensible aux variables sociales. La dernière étude (Chapitre VII) vise donc à explorer cette sensibilité du PPS vers une dimension sociale fondamentale, encore inexplorée: la propriété privée. Les résultats de la quatrième étude indiquent que la propriété d'un objet, qu'elle soit considérée comme individuelle ou partagée, est essentielle pour l'émergence des propriétés dynamiques du PPS. Les stimuli visuels influencent effectivement la perception tactile d'une manière plus marquée au début du mouvement, mais seulement lorsque l'objet appartient au participant. Il convient de noter qu'un effet similaire apparaît également lorsque l'on observe une autre personne agir sur l'objet qui lui appartient... [etc] / The zone that surrounds our body is of vital importance: we carefully monitor the objects (both animate and inanimate) that enter the boundaries of the immediate space around the body to interact with them. In the neurocognitive field such a space is captured by the concept of peripersonal space (PPS), a highly plastic representation that integrates tactile and visual stimuli presented on, and close to, the body. This system seems to contribute to the efficient guidance of actions, yet, a clear demonstration of a prominent role of PPS in control of actions is critically lacking. Strong support for this would derive from evidence that PPS plastic changes occur before rather than after movement onset. The results from the first study (Chapter II) reveal that visual and tactile information strongly interact already during the planning phase of action and this visuo-tactile interaction is further enhanced during subsequent movement phases. Such a visuo tactile remapping of PPS that temporally precedes and subsequently accompanies overt motor execution is ideally suited to planning and guiding actions. Recently, it has been suggested a possible involvement of PPS in the guidance of motor interactions between individuals. In social psychology, the space around the body is termed interpersonal space (IPS), defined as the area individuals maintain around themselves into which others cannot intrude without arousing discomfort. Because of some similarities between the PPS and IPS constructs, some authors have raised the question of whether they share some functional features. The second aim of my thesis is to test this hypothesis by taking advantage of another PPS remapping, namely that one induces by tool-use. The results of the second study (Chapter IV) show that “standard” tool-use ‘extends’ PPS, as measured by reaching distance toward a peer, but does not affect IPS, as measured by the comfort distance toward the same peer. In the third investigation (Chapter V), we introduced a novel form of “social” tool-use setting to test for both sensorimotor and social plasticity of the two spaces. The findings that social tool–use ‘extends’ PPS and ‘reduces’ IPS, inducing opposite changes on each representation, clearly disconfirms the hypothesis . that there might be functional overlap between these sectors of space. Such examples of functional dissociation may therefore be sufficient to warn scholars to refrain from risky conflations between the two concepts. If the assumption of functional identity with IPS does not appear to be legitimate, it is true that PPS is sensitive to social features. The last study (Chapter VII) is thus aimed at probing this sensitivity of PPS to a so far unexplored but fundamental social dimension: ownership. The results from the forth study indicate that, whether considered to be as individual or shared property, ownership of an object is critical for the PPS dynamic properties to emerge. Visual stimuli affected touch perception more strongly at the movement onset than before, but only when the object belonged to the acting participant. Interestingly, a similar remapping was found when simply observing the peer acting on her own belonging. In a follow-up experiment we investigated PPS plastic changes when property of the target object was shared between the two agents. In this case, PPS remapping emerged not only when acting in first person, but also when observing the peer acting upon the shared object. Taken together, these findings critically inform current theoretical models about space around our body and about its function in our sensorimotor and social inter-actions
62

Ranging, Behavior, and Ecology of the Buraiga Chimpanzee Community, Kibale National Park, Uganda

Edwards, Wren Ingrid 05 June 2023 (has links)
No description available.
63

Cognition physique chez l’oiseau : général ou adapté ? / Physical cognition in birds : general or adapted?

Danel, Samara 29 January 2018 (has links)
La cognition physique correspond à l’ensemble des connaissances que nous possédons sur les objets inanimés qui nous entourent, et à leurs relations avec l’environnement. Selon l’hypothèse de l’intelligence sociale générale, la cognition physique se serait développée tel un continuum (à l’instar de tous les autres domaines cognitifs), chez les espèces vivant au sein de groupes sociaux complexes. A l’inverse, l’hypothèse de l’intelligence sociale adaptée suppose que le fait d’interagir avec des congénères a permis de développer des capacités cognitives supérieures, mais spécifiques, du domaine social. Bien que les recherches relatives à l’évolution de la cognition physique se soient d’abord focalisées sur les primates, nous savons aujourd’hui que certains oiseaux sont capables d’interagir de manière complexe avec leur monde physique, en utilisant et en fabriquant des outils (p. ex., voir Article 1). Néanmoins, de nombreuses familles aviaires restent à ce jour non étudiées, laissant ce débat en suspens. L’objectif général de ce travail de recherche est de contribuer à une meilleure compréhension des facteurs responsables de l’évolution de la cognition, grâce à l’apport théorique de l’hypothèse de l’intelligence sociale suivant son aspect général et adapté. Quatre espèces, jusqu’alors inconnues sur le plan cognitif, ont été sélectionnées suivant leur degré de socialité mais également la spécificité de leur écologie. Ce dernier facteur, trop souvent ignoré en biologie du comportement, est crucial pour apprécier le comportement dans son ensemble. Nous avons ainsi estimé la faculté des sujets, à savoir des pélicans blancs Pelecanus onocrotalus (sociaux) et des euplectes vorabés Euplectes afer afer (grégaires), à reproduire le comportement d’un congénère (domaine social) grâce à un test d’apprentissage social (Articles 2 part I & 3). Nous avons ensuite évalué leur capacité à se servir d’un objet pour obtenir une récompense alimentaire hors de portée (domaine physique), grâce à un test d’utilisation d’outils (Articles 2 part II & 4). Bien que les pélicans fussent capables de résoudre rapidement la tâche d’apprentissage social, ils ne réussirent pas à utiliser spontanément des outils (cf. discussion Article 2 part II). A l’instar du pélican, l’euplecte imita le comportement d’un congénère. Néanmoins, il échoua à utiliser des outils dans le contexte du fourragement, malgré le fait que cet oiseau utilise et fabrique des outils de manière complexe pour construire son nid.A défaut d’avoir pu étudier l’apprentissage social et l’utilisation d’outils chez deux autres espèces sociales, les calaos terrestres Bucorvus et les toucans Ramphastidae, cette recherche consistait également à administrer un paradigme permettant d’apprécier le domaine physique : le test de la ficelle (Articles 5 & 6, respectivement). La tâche impliquait de tirer sur une ficelle afin d’obtenir une récompense alimentaire accrochée à son extrémité. Les calaos terrestres échouèrent à tirer sur la ficelle dans la configuration verticale, mais réussirent rapidement la tâche dans diverses conditions de la configuration horizontale. Chez les toucans, cependant, un seul sujet réussit le test dans sa configuration verticale. Les résultats obtenus nous permettent de réfuter l’hypothèse de l’intelligence sociale dans son aspect général. En effet, aucun lien ne semble se dessiner entre le domaine social et physique chez les quatre espèces aviaires étudiées. Bien que l’hypothèse de l’intelligence sociale soit soutenue depuis plus de quatre décennies, une théorie unitaire est requise. Dans ce cadre, un nouveau modèle d’évolution cognitive, permettant d’évaluer l’importance de l’intelligence générale chez une espèce donnée, pourrait s’avérer particulièrement prometteur. / Physical cognition is defined as the knowledge that we possess about the inanimate objects surrounding us, and their relation with the environment. According to the general social intelligence hypothesis, physical cognition would have developed as a continuum (like all the other cognitive domains), in species living in complex social groups. By contrast, the adapted social intelligence hypothesis assumes that interacting with conspecifics has allowed development of superior, but specific, cognitive capacities related to the social realm. Although research on the evolution of cognition first focused on primates, we now know that some avian species are capable of interacting with their physical world in a complex way by using and manufacturing tools (e.g., Article 1). However, to date, various bird families are still unstudied, leaving open this debate. The general goal of this work is to contribute to a better understanding of the factors acting on the evolution of cognition, thanks to the theoretical input of the social intelligence hypothesis according to its general and adapted aspect. Four species that had never been studied in cognitive studies before were selected according to their degree of sociality but also according to the specificity of their ecology. This latter factor has been largely ignored in behavioural biology, although it is crucial for a more holistic comprehension of the behaviour. This work aimed to assess the ability of two avian species, great white pelicans Pelecanus onocrotalus (social birds) and yellow-crowned bishops Euplectes afer afer (gregarious birds), to imitate the behaviour of a trained conspecific (social domain) with a social learning task (Articles 2 part I & 3, respectively). Subsequently, we have studied heir ability to use an object in order to get an out-of-reach food reward (physical domain) with a tool use task (Articles 2 part II & 4). Although pelicans were capable of rapidly solving the social learning task, they did not succeed in using tools spontaneously (cf. discussion Article 2 part II). The bishops were able to imitate the behaviour of a conspecific, however they were not capable of using tools in the foraging context, although these birds are well known to use and manufacture tools in quite a complex way in order to build their nests. We have also administrated to two other avian social species, ground-hornbills Bucorvus and toucans Ramphastidae, an experimental paradigm to assess cognition in the physical domain: the string-pulling test (Articles 5 & 6, respectively). The task involved pulling on a string in order to obtain a food reward attached to its extremity. Ground-hornbills failed to pull on the string in the vertical configuration, but rapidly solved the task in various conditions within the horizontal configuration. In toucans, however, only one subject succeeded in the vertical configuration. These results allow us to refute the social intelligence hypothesis in its general aspect. Indeed, no link seems to be drawn between the social and the physical domains in the four species studied. Although the social intelligence hypothesis is supported since decades, a unitary theory is required. A new model of cognitive evolution, that allows assessing the importance of general intelligence in species, may be particularly promising.
64

Análise anatomo-funcional dos músculos do antebraço e a citoarquitetura do neocórtex occipital de Cebus libidinosus / Anatomical-functional analysis of forearm muscles and cytoarchitecture of the neocortex of the occipital Cebus libidinosus

PRADO, Yandra Cássia Lobato do 10 June 2010 (has links)
Made available in DSpace on 2014-07-29T15:13:39Z (GMT). No. of bitstreams: 1 Yandra Cassia Lobato do Prado.pdf: 3346090 bytes, checksum: 459271b973e2cf45dae272f74f535fe4 (MD5) Previous issue date: 2010-06-10 / Primates are known for larger brain size, enhanced handling and cognitive abilities and increasingly complex social behavior. Many studies have been conducted with the neotropical primates of the genus Cebus, known as capuchin monkey, regarding their behavior, tool use, encephalization index and memory. These studies are justified because these primates present high cognitive faculty and other biological characteristics that make them similar to Old World primates. This thesis rendered possible the production of two articles. The first one is entitled Anatomical description of the extensor muscles of the forearm associated with cognition and tool use in Cebus libidinosus . In this article, a comparative analysis between the anatomy of the forearm muscle of this genus and that the one of other primates that, individually or jointly, act in the hands allowing more or less specialized movements of the fingers, relating them to the use of tools and to the cognitive aspects of Cebus spp. described in the literature. There were evident similarities between the extensor muscles in C. libidinosus primates and the correspondent muscles in humans and chimpanzees; however, there were differences when compared to baboons. The structure and differentiation of the forearm muscles of Cebus spp., together with its previously known encephalization index, corroborate the association between its manual ability and cognitive and behavioral aspects in primates. The second article is entitled "Cytoarchitecture of the occipital neocortex of Cebus libidinosus . Its purpose was to analyze the cytoarchitecture of the occipital cortex using the technique of Golgi-Cox, the qualitative and quantitative aspects provided by this technique of impregnation of neurons, and to compare them with data from the literature. Primary and secondary visual areas are located in the occipital neocortex, and in C. libidinosus, the histological organization of these areas is similar to humans and other primates and it is characterized by the predominance of granular neurons and the presence of transversal fibers in the fourth layer. Although the Golgi-Cox method allowed individual observation of neurons and their extensions, the weak distinction between neurons and glial cells impaired neuron counting. These data, nevertheless, will grant further cell density comparison of other cortical areas between Cebus spp. and other primates. Aiming to contribute to the foundations of studies related to the evolution of primate cognition, this study related morphology, as a science, to the numerous observations on the behavior of capuchin monkeys. The comparative approach to study the morphology of the musculoskeletal and neural apparatus of C. libidinosus will allow data inference in areas of cognitive science and related areas. / Os primatas são caracterizados pelo maior tamanho do cérebro, pelo aprimoramento de habilidades manipulativas e cognitivas e desenvolvimento de comportamento social complexo. Muitos estudos têm sido realizados com os primatas neotropicais do gênero Cebus, conhecidos por macaco-prego, relativos a comportamento e uso de ferramentas, índice de encefalização e memória. Esses estudos se justificam em razão desses primatas apresentarem elevada capacidade cognitiva e outras características biológicas que os torna similares aos primatas do Velho Mundo. A presente tese gerou a produção de dois artigos. O primeiro intitulado Descrição anatômica dos músculos extensores do antebraço de Cebus libidinosus associada a aspectos cognitivos e ao uso de ferramentas , propôs-se a análise comparativa entre a anatomia muscular do antebraço com àquela de outros primatas que, individual ou conjuntamente, atuam nas mãos possibilitando movimentos mais ou menos especializados dos dedos, relacionando-se ao uso de ferramentas e aspectos cognitivos de Cebus spp. descritos na literatura. Observaram-se evidentes similaridades entre os músculos extensores de C. libidinosus com os músculos correspondentes em humanos e chimpanzés, porém houve diferenças desses músculos em relação aos babuínos. A estrutura e diferenciação dos músculos do antebraço do Cebus spp., associados ao seu já conhecido índice de encefalização, reforçam a associação entre suas habilidades manuais e os aspectos cognitivos e comportamentais em primatas. O segundo artigo intitulado Citoarquitetura do neocórtex occipital de Cebus libidinosus propôs-se a análise da citoarquitetura do córtex cerebral occipital utilizando a técnica de Golgi-Cox, sob os aspectos qualitativos e quantitativos que esta técnica de impregnação de neurônios proporciona e, compará-los com dados descritos na literatura. No neocórtex occipital estão situadas as áreas visuais primárias e secundárias e, em C. libidinosus, a organização histológica destas áreas apresenta, tal como em outros primatas não-humanos e o homem, a predominância de neurônios granulares e a presença de estrias de Baillarger na quarta camada. O emprego da técnica de Golgi-Cox permitiu a visualização individual dos neurônios e seus prolongamentos, entretanto quanto à análise quantitativa apresenta como limitação a dificuldade em diferenciar células neuronais e não-neuronais. Estes dados permitirão futuras comparações entre diferentes áreas corticais de Cebus spp. e outros primatas. Com o intuito de contribuir com as bases dos estudos relacionados à evolução da cognição de primatas, este trabalho relacionou a morfologia, tal como ciência que é, com as inúmeras observações sobre comportamento do macaco-prego. A abordagem comparativa no estudo da morfologia músculo-esquelética e do aparato neural do C. libidinosus permitirá inferir dados às áreas da ciência cognitiva e áreas correlatas.
65

Sensorimotor learning and simulation of experience as a basis for the development of cognition in robotics

Schillaci, Guido 11 March 2014 (has links)
Heutige Roboter sind nur begrenzt in der Lage etwas zu erlernen, sich unerwarteten Umständen anzupassen oder auf diese zu reagieren. Als Antwort auf diese Fragen, develomental robotics setzt sich den Aufbau eines künstlichen Systems zum Ziel, das motorische und kognitive Fähigkeiten analog zur menschlichen Entwicklung durch Interaktion mit der Umgebung entwickeln kann. In dieser Arbeit wird ein ähnlich Ansatz verwendet, mit Hilfe dessen grundlegende Verhaltenskomponenten identifiziert werden sollen, die eine autonome Aneignung motorischer und kognitive Fähigkeiten durch die Roboter ermöglichen könnten. Diese Arbeit untersucht die sensomotorische Interaktion als Mittel zur Schaffung von Erfahrungen. Es werden Experimente zu explorative Verhaltensweisen zur Aneigung von Arbewegungen, der Werkzeugnutzung und von interaktiven Fähigkeiten vorgestellt. In diesem Rahmen wird auch die Entwicklung sozialer Fähigkeiten, insbesondere durch joint attention, behandelt. Dabei werden zwei Vorraussetzugen zu joint attention untersucht: Zeigegesten und Erkennung von visueller Salienz. Dabei wurde das Framework der interen Modelle für die Darstellung von sensomotorischen Erfahrungen angewendet. Insbesondere wurden inverse und Vorwärtsmodelle mit unterschiedlichen Konfigurationen am sensorischen und motorischen Daten, die vom Roboter durch exploratives Verhalten, durch Beobachtung menschliche Vorführern, oder durch kinästhetisches Lehren erzeugt wurden geschult. Die Entscheidung zu Gunsten dieses Framework wurde getroffen, da es in der Lage ist, sensomotorische Zyklen zu simulieren. Diese Arbeit untersucht, wie grundlegende kognitive Fähigkeiten in einen humanoiden Roboter unter Berücksichtigung sensorischer und motorischer Erfahrungen implementiert werden können. Insbesondere wurden interne Simulationsprozesse für die Implementierung von Kognitivenfahigkeiten wie die Aktionsauswahl, die Werkzeugnutzung, die Verhaltenserkennung und die Self-Other distinction, eingesetzt. / State-of-the-art robots are still not properly able to learn from, adapt to, react to unexpected circumstances, and to autonomously and safely operate in uncertain environments. Researchers in developmental robotics address these issues by building artificial systems capable of acquiring motor and cognitive capabilities by interacting with their environment, inspired by human development. This thesis adopts a similar approach in finding some of those basic behavioural components that may allow for the autonomous development of sensorimotor and social skills in robots. Here, sensorimotor interactions are investigated as a mean for the acquisition of experience. Experiments on exploration behaviours for the acquisition of arm movements, tool-use and interactive capabilities are presented. The development of social skills is also addressed, in particular of joint attention, the capability to share the focus of attention between individuals. Two prerequisites of joint attention are investigated: imperative pointing gestures and visual saliency detection. The established framework of the internal models is adopted for coding sensorimotor experience in robots. In particular, inverse and forward models are trained with different configurations of low-level sensory and motor data generated by the robot through exploration behaviours, or observed by human demonstrator, or acquired through kinaesthetic teaching. The internal models framework allows the generation of simulations of sensorimotor cycles. This thesis investigates also how basic cognitive skills can be implemented in a humanoid robot by allowing it to recreate the perceptual and motor experience gathered in past interactions with the external world. In particular, simulation processes are used as a basis for implementing cognitive skills such as action selection, tool-use, behaviour recognition and self-other distinction.

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