The following thesis examines factors that affect children’s imitation, and presents evidence that imitation is a composite ability which involves multiple mechanisms developing throughout childhood. In Chapter 1 previous findings are reviewed to highlight the mechanisms underlying the ability to reproduce other people’s actions. The evidence suggests that imitation, whilst based on basic action control mechanisms in infancy, is also affected by higher-order cognitive processes in later childhood. Previous literature is still unclear on how the influence of such processes changes at different ages. Chapter 2 used a successive-models task with children aged 2 to 12 years to reveal how children’s imitation changes with age. Results showed that whilst children under the age of 5 years did not imitate deviant models as much as the first model, children above the age of 6 years begin to copy multiple models faithfully, particularly after the age of 10 years. Chapter 3 investigated the role of multiple factors that may have made children under the age of 5 years imitate deviant models less than the original model. In particular, it was found that model evaluations, object associations, and motor inhibitory skills all affect children’s imitation of multiple models. These findings support the interpretation that imitation requires different abilities depending on the type of action that is being imitated. Chapter 4 shows that children’s imitation also depends on the type of goal that they associate with the action. By pre-school age children will imitate actions faithfully if they believe that the goal of the action was the movement itself. The results of the thesis support the idea that imitation, while involving general processes of action control, is also affected in a top-down manner by higher-order cognitive abilities after infancy.

Les robots vont peu à peu intégrer nos foyers sous la forme d’assistants et de compagnons,humanoïdes ou non. Afin de remplir leur rôle efficacement ils devront s’adapter àl’utilisateur, notamment en apprenant de celui-ci le savoir ou les capacités qui leur fontdéfaut. Dans ce but, leur manière d’interagir doit être naturelle et évoquer les mêmesmécanismes coopératifs que ceux présent chez l’homme. Au centre de ces mécanisme setrouve le concept d’action : qu’est-ce qu’une action, comment les humains les reconnaissent,comment les produire ou les décrire ? La modélisation de toutes ces fonctionnalitésconstituera la fondation de cette thèse et permettra la mise en place de mécanismescoopératifs de plus haut niveau, en particulier les plan partagés qui permettent à plusieursindividus d’oeuvrer de concert afin d’atteindre un but commun. Finalement, je présenteraiune différence fondamentale entre la représentation de la connaissance chez l’homme etchez la machine, toujours dans le cadre de l’interaction coopérative : la dissociation possibleentre le corps d’un robot et sa cognition, ce qui n’est pas imaginable chez l’homme. Cettedissociation m’amènera notamment à explorer le « shared experience framework », unesituation dans laquelle une cognition artificielle centrale gère l’expérience partagée demultiples individus ayant chacun une identité propre. Cela m’amènera finalement àquestionner les différentes philosophies de l’esprit du point de vue de l’attribution d’unesprit à une machine et de ce que cela impliquerai quant à l’esprit humain. / Robots will gradually integrate our homes wielding the role of companions, humanoids ornot. In order to cope with this status they will have to adapt to the user, especially bylearning knowledge or skills from him that they may lack. In this context, their interactionshould be natural and evoke the same cooperative mechanisms that humans use. At thecore of those mechanisms is the concept of action: what is an action, how do humansrecognize them, how they produce or describe them? The modeling of aspects of thesefunctionalities will be the basis of this thesis and will allow the implementation of higherlevel cooperative mechanisms. One of these is the ability to handle “shared plans” whichallow two (or more) individuals to cooperate in order to reach a goal shared by all.Throughout the thesis I will attempt to make links between the human development ofthese capabilities, their neurophysiology, and their robotic implementation. As a result ofthis work, I will present a fundamental difference between the representation of knowledgein humans and machines, still in the framework of cooperative interaction: the possibledissociation of a robot body and its cognition, which is not easily imaginable for humans.This dissociation will lead me to explore the “shared experience framework, a situationwhere a central artificial cognition manages the shared knowledge of multiple beings, eachof them owning some kind of individuality. In the end this phenomenon will interrogate thevarious philosophies of mind by asking the question of the attribution of a mind to amachine and the consequences of such a possibility regarding the human mind.

A longitudinal study of infants and their mothers was conducted to explore the development of imitation and approximations to imitation. During a 10-minute unstructured play session, researchers observed two mother-infant dyads once per week for twelve weeks, while they played at home. The data presented represents infants between the ages 5 and 34 weeks. The methodology employed was based on the methods described by Hart and Rilsey (1999). Observations were coded based on the topography of the mother's and infant's behavior and included vocalizations, facial movements, motor movements, and object manipulation. The data are analyzed and discussed in terms of its relevance to autism intervention.

Cette thèse tente de répondre à deux questions principales : qui est le saint pour Péguy, et qu’est-ce que le saint, chez Péguy, fait au monde. Dans la première partie la réflexion est axée sur les saints (reconnus comme tels par l’Église), par, ainsi que les « saints » (selon un procédé de mise en relief littéraire, propre à Péguy) qui apparaissent dans les œuvres de Péguy. Nous tâchons d’y répondre à la question : qui est saint chez Péguy, qu’est-ce qui, selon cet auteur, fait d’un homme un saint, un Juste ? Péguy parle de figures d’exemplarité et réfléchit sur ses formes possibles : l’héroïsme, la sainteté, le génie. Il a sa propre liste de vertus (ce qui fait d’un homme un saint) qui sont parfois différentes des vertus traditionnellement attribuées aux saints catholiques. L’impact de son cheminement vers la foi sur sa philosophie de l’histoire mène Péguy vers un questionnement sur la sainteté même. C’est pourquoi la deuxième partie de cette thèse cherche la réponse à la question : que fait le saint au monde, dans le monde, pour le monde, comment le saint chez Péguy change le monde ? Il s’agit en somme de cerner le rôle de la sainteté dans le monde, y compris en tant que concept éthique revisité. Nous nous penchons aussi sur le ou les rôles que Péguy attribue au saint dans la société : solitaire parce que différent des autres humains, solidaire parce qu’agissant dans ce monde dans lequel il poursuit l’œuvre de l’Incarnation / The thesis aims at answering two main questions: Who is a saint from the point of view of Péguy. What does a saint do in the world.In the first part, the author approaches a set of questions: who is a saint? what makes a person saint or just for Péguy? To answer this, the author analyses the examples of saints in the works of Péguy, considering not only the saints recognised by church, but equally saints, specific to Péguy.Péguy portray saints as models for imitation, and he examines a diversity of forms these models could take: a saint, a hero, a genius. These «saint» created by Péguy possess a number of «virtues», sometimes radically different to those traditionally attributed to saints which makes them saint from the point of view of Péguy. Since the saint for Péguy is presented in direct connection with the world he lives in, the second part of the thesis answers the questions: what does a saint does in the world, for the the world, with the world. How a saint’s activity changes the world? In this part of the thesis, we approach the definition of the role of the sanctity in the world as imagined by Péguy. Péguy attributes two roles to a saint in the society: solitude and solidarity. A saint is lonely, because he is different from other human beings, but at the same time, a saint is united with the world in acting in the world in order to convey the incarnation, the embodiment of God in this world.For Péguy sanctity reveals itself as the new ethics instrumental in the construction of a new, harmonious city, which Péguy tries to build throughout his writings. This new ethics is supposed to revolutionise the current world, changing both morale and social paradigms

This study examines the effects of imitating other musicians on one’s instrument as well as how this impacts one’s playing. Furthermore, it seeks to illuminate the question of what the ear notices first when listening non-analytically to music with the goal of copying a certain way of playing. The result of the work would be demonstrated at a concert with mostly original music. A selection of musicians and recordings to imitate was made, and the imitation happened on 8 different occasions with varying constellations and different musicians participating. During the process it was made clear that the musician’s ear mainly picks up on the overall feeling and attitude of soloists, but also some small details such as nuances in timbre and intonation. In the preparation of the concert some songs were more or less tailored to a certain way of playing, inspired by the recordings. The resulting concert clearly shared some characteristics with some of the recordings, as well as having little in common with others.

Reverse engineering, defined as extracting information about a product from the product itself, is a common industry practice for gaining insight into innovative products. Both the original designer and those reverse engineering the original design can benefit from estimating the time and barrier to reverse engineer a product. This thesis presents a set of metrics and parameters that can be used to calculate the barrier to reverse engineer any product as well as the time required to do so. To the original designer, these numerical representations of the barrier and time can be used to strategically identify and improve product characteristics so as to increase the difficulty and time to reverse engineer them. One method for increasing the time and barrier to reverse engineer a product – presented in this thesis – is to treat material microstructures (crystallographic grain size, orientation, and distribution) as continuous design variables that can be manipulated to identify unusual material properties and to design devices with unexpected mechanical performance. A practical approach, carefully tied to proven manufacturing strategies, is used to tailor material microstructures by strategically orienting and laminating thin anisotropic metallic sheets. This approach, coupled with numerical optimization, manipulates material microstructures to obtain desired material properties at designer-specified locations (heterogeneously) or across the entire part (homogeneously). As the metrics and parameters characterizing the reverse engineering time and barrier are also quantitative in nature, they can also be used in conjunction with numerical optimization techniques, thereby enabling products to be developed with a maximum reverse engineering barrier and time – at a minimum development cost. On the other hand, these quantitative measures enable competitors who reverse engineer original designs to focus their efforts on products that will result in the greatest return on investment. While many products were analyzed in an empirical study demonstrating that the characterization of the time to reverse engineer a product has an average error of 12.2%, we present the results of three different products. Two additional examples are also presented showing how microstructure manipulation leads to product hardware with unexpected mechanical performance effectively increasing reverse engineering time and barrier.

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Imitation enables social communication and is said to be deficient in people with autism. Yet little research has been done into what differentiates poor from good imitators. This project employed novel quantifiable methods of testing manual and facial imitation to determine how ability as well as empathy (which also enables social interaction) correlate with brain activation using functional Magnetic Resonance Imaging (fMRI). Manual imitation was tested (in- and outside the MRI-scanner) by asking participants to copy model drawings using a touchscreen that captured their kinematic data. Facial imitation was tested by asking people to copy composite facial expressions and blind-scoring the resulting imitation attempts. First, 28 adults were tested to establish what brain areas enable better imitation and how these relate to empathic abilities. Then, 25 young people with autism and 23 matched controls were tested to see how purported group differences in imitation related to brain activation patterns across and within groups. Results revealed that manual imitation ability correlated with increased activation in different brain areas than facial imitation ability. There was only one area of significant overlap, between facial imitation ability and empathy. Young people with autism were found to be impaired on facial imitation, empathy and some aspects of manual imitation. Nevertheless, fMRI results indicated that ability and age differences played a more important role than autism diagnosis in regulating what brain areas were activated during imitation. Only for the facial imitation task did autistic participants appear to use a different neural mechanism, but this was still mediated by ability. Overall, this methodologically innovative project shows that investigating individual differences in imitation ability, regardless of a diagnosis of autism, can shed more light on what neural mechanisms are crucial for imitation.

No description available.

Mémoire numérisé par la Direction des bibliothèques de l'Université de Montréal.