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Les bases cognitives de l’évolution culturelle cumulative

Abstract : Culture is a set of information that members of a group share through social transmission (imitation, communication ...) in the form of ideas, behaviors or artifacts. Cultural traits developed by humans are more complex than in other species. This is attributed to the process of cultural evolution which, in humans, is cumulative. Along with their diffusion, cultural traits become more complex and perform progressively better by accumulating changes over generations, a process called the ratchet effect. The project of this thesis was to investigate cognitive mechanisms involved in the emergence of the ratchet effect. We simulated this phenomenon under experimental conditions using thechain transmission method in order to test the predictive power of technical reasoning, theory-of-mind skills, creativity and fluid intelligence in the constant progression of performances across generations. The first study investigated the role of these four factors in a mechanical problem solving task (tower construction with wires) in a Communication condition (i.e., participants are allowed to talk to each other) and an Observation condition (i.e., participants cannot communicate). Our strongest prediction regarding this paradigm involved technical reasoning, for having proven a better predictor of a ratchet effect than theory of mind skills. The same observation was made in both conditions, while theory of mind skills did not allow to predict any ratchet effect. The second study explored the influence of technical reasoning and theory-of-mind skills on the same task, in a Monitoring condition (i.e., participants communicate indirectly through a video feed) and a Blind condition (i.e., participants communicate verbally without seeing each other). Technical reasoning skills predicted once again the emergence of a ratchet effect, while theory-of-mind skills predicted the same effect in the Blind condition only. These results demonstrate the weight of technical reasoning in thecreation, transmission, and improvement of a material cultural trait, while theory-ofmind skills are involved only in a particularly abstract situation where individuals have no visual cues. The third study explored the conditions leading individuals to copy or innovate a technique or tool. Participants were tested in an unfamiliar situation, and were asked to achieve a material task (making a basket out of everyday life objects). Conditions varied based on opacity (i.e., mechanisms involved between the initial state and the final product are difficult to understand) and risk levels. It turned out that participants were more likely to reproduce the same actions and objects used in a demonstration when tested in a risky and opaque condition, while they used more often new objects and new actions in a non-risky, transparent task.
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Submitted on : Monday, March 25, 2019 - 4:56:10 PM
Last modification on : Tuesday, November 19, 2019 - 10:42:32 AM
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  • HAL Id : tel-02078916, version 1



Emmanuel de Oliveira. Les bases cognitives de l’évolution culturelle cumulative. Psychologie. Université de Lyon, 2018. Français. ⟨NNT : 2018LYSE2144⟩. ⟨tel-02078916⟩



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