No description available.

The role of language has been identified as crucial in the cognitive development of young children, and has been observed on different time-scales. In particular, the real-time verbal mediation of behaviour has been studied in the context of private speech use and self-regulation, pioneered by Vygotsky and continued by others who followed this line of research. However previous studies have mainly attempted to find correlations between speech and self-regulatory behaviour, but have been unable to capture the dynamic and real-time temporal interactions between these phenomena. Hence, without being able to carry out a contextual analysis of the actual instances of temporal co-occurrence between speech and behaviour, correlational analysis is limited in determining the various kinds of verbal mediation that children spontaneously employ as strategies during problem-solving and while exercising self-regulation. The current study proposes ‘temporal pattern analysis’ as an effective method of extracting significantly recurring patterns of task-relevant speech and goal-directed behaviour, as they repeatedly occur in a stream of naturalistic behaviour which may also contain other temporally random events. These recurring temporal patterns are then contextually analysed, considering the pragmatic content of the speech involved and the goal-directedness of the behaviour towards a specific goal of the episode. Goal-directed episodes of behaviour in eight typically-developing preschool children were video-recorded during their self-initiated activities in the classroom as well as during a problem-solving task held in a laboratory setting. The proposed method of temporal and contextual analysis was used to examine the role of both private as well as social speech in the verbal mediation of self-regulatory behaviour during goal-attainment. A Contextual Model of Verbal Mediation was proposed in the study to account for the diverse functions that both social and private speech perform during verbal mediation of one’s own and others’ behaviour in a goal-directed setting, depending on the specific social and task-related context. A dynamic framework of assessment of performance was developed in the study, to account for both successful attempts at self-regulation as well as failures of self-regulation. The study also attempted to determine any consistent group differences in the styles of verbal mediation employed by the children, across the classroom and the laboratory settings.

Portés par l’évolution rapide d’Internet, les réseaux sociaux sont devenus de nouveaux moyens d’expression pour émettre et consulter des communications de bouche-à-oreille (BAO). Les marketeurs sont intéressés pour mieux utiliser ce BAO dans une politique de communication. Ils élaborent pour cela des stratégies de « sollicitation » consistant à demander à une personne de recommander une offre à ses proches en vue d’atteindre un but. Si l’utilisation de sollicitations se développe, la question de la réponse d’un individu à une sollicitation de BAO reste en suspens. En se basant sur la théorie du comportement dirigé vers un but (Perugini & Bagozzi, 2001), cette recherche propose un modèle général de la réponse à une sollicitation de BAO qui intègre l’influence de la formulation de la sollicitation (gains vs. pertes), de l’éloignement de l’échéance et du type de projet. Le modèle est testé dans le contexte des campagnes de financement participatif où la sollicitation de BAO est fréquemment utilisée pour augmenter le faible taux de succès des campagnes (20%). Les résultats de six études montrent que (1) les individus répondent plus favorablement à une sollicitation de BAO quand l’échéance est proche et que cet effet dépend de la formulation de la sollicitation. (2) En adaptant la formulation à l’éloignement de l’échéance, une sollicitation est en mesure de rendre l’action de BAO plus désirable et de générer une émotion anticipée de fierté ce qui en retour augmente l’intention de BAO. L’effet modérateur du niveau de risque social est aussi validé dans la réponse à la sollicitation. (3) Finalement, la sollicitation de BAO permet bien de développer la visibilité et d’accroître le succès d’une campagne. / Driven by the rapid evolution of the Internet, online social networks have become new channels of expression to issue and consult Word-of-Mouth (WOM). Marketers are increasingly interested in better using WOM in a communication policy. They develop strategies of “solicitation” for asking a person a recommendation of an offer to his family and acquaintances in order to achieve a goal. If the use of solicited WOM is growing, the question of an individual's response to a WOM solicitation remains unsettled. Drawing on Goal-Directed Behaviour theory (Perugini & Bagozzi, 2001), this research proposes a general model of the response to a WOM solicitation which integrates the influence of the solicitation formulation (gain vs loss), time remaining before the deadline and the type of project. The model is tested in the context of crowdfunding where a WOM solicitation is frequently used to increase the campaigns' low success rate (20%). The results of six studies show that (1) individuals respond more favourably to a WOM solicitation when the deadline is close and that effect depends on the formulation. (2) By adapting the formulation to the deadline, a solicitation is able to make the WOM action more desirable and generate an anticipated emotion of pride which in turn increases the WOM intention. The moderating effect of social risk is also validated in the response to a solicitation. (3) Finally, a WOM solicitation makes it possible to develop the visibility and increases the campaign' success rate.

Humans and other animals systematically discount the value of future rewards as a function of their delay, and individual differences in the steepness of this ``delay discounting'' are predictive of a range of important real-world outcomes. Episodic future thinking, the mental simulation of episodes in the personal future, is one means by which to curb delay discounting. This thesis seeks to contribute to our understanding of how this effect occurs. The account that predominates in the literature is that episodic future thinking simulates the experience of future rewards, enabling their undiscounted value to be appreciated in the present. This thesis takes this account as a starting point, formalizing it in a mathematical model and carrying out several experimental studies to test its predictions. We find that key predictions are not borne out and develop an alternative account in which simulated experience plays a less central role. / Thesis / Doctor of Philosophy (PhD) / Pursuing our goals for the future usually means sacrificing immediate gratification, yet we often make decisions that are not in our best interest over the long term. This is because we assign lower subjective value to future rewards the further they are from the present. Individuals differ in how much they devalue future rewards, and these differences are related to many real-world outcomes. Our tendency to devalue future rewards is reduced when we vividly imagine the future in a process called ``episodic future thinking,'' and this thesis seeks to understand how this effect occurs. The most obvious explanation would seem to be that episodic future thinking ``simulates'' the experience of future rewards and allows us to recognize their value in the present. However, using results from several experimental studies, I argue that this may not be the best explanation after all, and I develop an alternative.

The purpose of this thesis was to develop methodology by which treatments for the cognitive impairments in Huntington's disease (HD) could be tested. As such, the thesis focused mainly on evaluating rats with quinolinic acid (QA) lesions of the striatum, as this manipulation mimics some aspects of the neural damage in Huntington's disease, to try to identify cognitive deficits of HD resulting from cell loss in the striatum. In the first part (Chapters 3-5), the role of the striatum in implicit memory was investigated. Chapter 3 compared the performance of rats and humans on a reaction time task that evaluated implicit memory by presenting visual stimuli with differing probabilities which change over time. Although rats made higher percentage of incorrect responses and late errors, both groups showed a similar pattern of reaction times. Chapter 4 investigated whether implicit memory (the computation of probabilities to predict the location of a stimulus) was affected by selective blockade of dopaminergic transmission at the D1 or D2 receptors by SCH-23390 and raclopride, respectively. Reaction times were slower with SCH-23390 and raclopride, but only SCH-23390 reduced errors to the least probable target location. Chapter 5 used the same task to evaluate implicit memory in rats with QA lesions of the dorsomedial striatum (DMS). Implicit memory was not affected by lesions of the DMS, which suggested that once a task that requires implicit memory has been learned, the DMS was not involved in sustaining the performance of the task. The second part of this thesis (Chapter 6), explored the contribution of the DMS in habit formation. DMS lesioned rats did not show habitual responding, and were not impaired in learning a new goal-directed behaviour. The third part (Chapters 7 and 8), investigated the role of the dorsal striatum in reversal learning, attentional set-formation, and set-shifting. Dorsal striatum lesioned rats were not impaired in reversal learning, but had a diminished shift-cost, which suggested that dorsal striatum lesions disrupted the formation of attentional sets. These results showed that although QA lesions of the dorsal striatum mimic some aspects of the neural damage in HD, they did not result in the same cognitive deficits observed in patients with HD, at least using the tasks presented in this thesis. However, other animal models of HD could be evaluated using the different tasks presented in this thesis to continue the search of a reliable animal model of HD in which treatments for the disease could be evaluated.