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It’s difficult not to be amazed by the intricate process through which a honeybee swarm selects anew nest site. By exploring different options and sharing information with one another, the beescan collectively choose a single site. A key feature of these collective decisions is that they arenot directed by a centralized planner, but instead arise entirely from the interactions of individualswith each other and their environment. Inspired by such natural phenomena, roboticists are nowimplementing similar strategies in robot swarms to enhance collective decision-makingAs a social species, humans also frequently make collective decisions. Many important decisionsfor our societies are not made by a single individual but emerge from extensive verbal discussionsbetween multiple individuals. This dissertation aims to build a conceptual and experimentalbridge linking the study of human collective decision making with the more embodied collectivedecision making of animal and robotic swarms, which mostly take place through movements inphysical space. To do so, we place human participants in the type of embodied decision makingscenarios that swarms usually operate in.We created a virtual environment in which large groups of human participants can interact withone another and perform various tasks that are commonly studied in swarm robotics research. Intwo behavioral experiments, we used this virtual environment to study human behavior duringcollective decision making. In the first experiment, we studied how participants can form acollective perception of their environment by each exploring some part of the environment andthen sharing that information. In a subsequent experiment, we study how a group of participantscan select the best site in their environment while only using movement-based communication.The third study presented in this thesis reports on how human participants can implicitly signaltheir confidence in their movements during decision making in a shared physical, Doctorat en Sciences psychologiques et de l'éducation, info:eu-repo/semantics/nonPublished

Face pareidolia is the illusory perception of a face in ambiguous objects or patterns [1], as reflected by face-selective electroencephalographic (EEG) activity in both adults [2] and infants [3]. However, the perceptual interpretation of these ambiguous stimuli depends on the context in which they are presented [4,5]. In particular, we recently found that, in adults [5], ambiguous face-like stimuli are interpreted as faces in a non-face context and as non-face objects in a face context. Accordingly, here, we aim to explore how visual context shapes the perception of ambiguous stimuli early in life. We measured scalp EEG activity in 4-to-6 months-old infants using a frequency-tagging approach which is particularly suited to test infants because it allows for short and efficient recordings, has an excellent signal-to-noise ratio and is immune to most artifacts [6,7]. Infants were exposed to 20-second sequences of natural images presented at a rate of 6 images per second (6 Hz), with ambiguous stimuli inserted every 5th image (at 1.2 Hz), and face or house images inserted every 4th image (at 1.5 Hz), defining a visual face or non-face context, respectively. Preliminary data (N=10 infants) reveal that the brain response to ambiguous stimuli is weaker in infants than in adults. Contrary to the adult responses, the infant response is also more face-like in the face context (with a typical temporo-parietal location of the response [3]) and shifts to a more occipital response in the non-face context. While these preliminary results still need to be consolidated, they suggest that the influence of visual context on the categorization of ambiguous stimuli changes throughout development, likely due to the effectiveness of perception at a given developmental stage. [1] Wardle et al. 2020, Nature communications [2] Rekow et al. 2022, Cognition [3] Rekow et al. 2021, PNAS [4] Rekow et al. 2022, NeuroImage [5] Bourgaux et al. in prep. [6] Kabdebon et al. 2022, NeuroImage [7] de H, info:eu-repo/semantics/published

Face pareidolia is the illusory perception of a face in ambiguous objects or patterns [1], as reflected by face-selective electroencephalographic (EEG) activity in both adults [2] and infants [3]. However, the perceptual interpretation of these ambiguous stimuli depends on the context in which they are presented [4,5]. In particular, we recently found that, in adults [5], ambiguous face-like stimuli are interpreted as faces in a non-face context and as non-face objects in a face context. Accordingly, here, we aim to explore how visual context shapes the perception of ambiguous stimuli early in life. We measured scalp EEG activity in 4-to-6 months-old infants using a frequency-tagging approach which is particularly suited to test infants because it allows for short and efficient recordings, has an excellent signal-to-noise ratio and is immune to most artifacts [6,7]. Infants were exposed to 20-second sequences of natural images presented at a rate of 6 images per second (6 Hz), with ambiguous stimuli inserted every 5th image (at 1.2 Hz), and face or house images inserted every 4th image (at 1.5 Hz), defining a visual face or non-face context, respectively. Preliminary data (N=10 infants) reveal that the brain response to ambiguous stimuli is weaker in infants than in adults. Contrary to the adult responses, the infant response is also more face-like in the face context (with a typical temporo-parietal location of the response [3]) and shifts to a more occipital response in the non-face context. While these preliminary results still need to be consolidated, they suggest that the influence of visual context on the categorization of ambiguous stimuli changes throughout development, likely due to the effectiveness of perception at a given developmental stage. [1] Wardle et al. 2020, Nature communications [2] Rekow et al. 2022, Cognition [3] Rekow et al. 2021, PNAS [4] Rekow et al. 2022, NeuroImage [5] Bourgaux et al. in prep. [6] Kabdebon et al. 2022, NeuroImage [7] de H, info:eu-repo/semantics/nonPublished

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Face-pareidolia is an illusory perception of a face in objects or patterns [1]. Although it is an illusion, it activates brain regions that are typically dedicated to the processing of faces [2]. This study aims to explore how visual context and infants’ visual experience shape the internal representations of these facelike objects. Facelike objects are used here because their ambiguous nature offers many ways to plasticity [3]. We also took advantage of the steady state evoked potentials (SS-EP) technique deriving from electroencephalography (EEG), which principle is based on the fact that the brain synchronizes to any kind of visual information presented in a periodic fashion [4]. SS-EP is particularly suited to test infants because it allows for short and efficient recordings, has an excellent signal-to-noise ratio and is immune to most artifacts [5]. In addition, we conceived an interlaced SS-EP design where 4 to 6 months infants are exposed to 20-second sequences of natural images presented at a rate of 6 images per second (6 Hz). Sequences differ regarding the context in which facelike stimuli are presented: a face context for odd sequences and a house context for even sequences. In this interlaced design, facelike stimuli are also repeated every 5th stimulus, so at the frequency of 1.2 Hz, and faces or houses every 4th stimulus, so at the frequency of 1.5 Hz. When fully collected, infant EEG data will be correlated with indices about their experience with faces collected through Ecological Momentary Assessment (EMA) questionnaires [6]. In a similar experiment with adults, we found that facelike objects generated a significant brain response, which the visual context modulated. In particular, we found that, in adults, the face- and house-context elicited facelike stimuli to be interpreted as objects and faces, respectively. With infants, we rather expect the brain responses to facelike objects to be weaker than in adults because of the protracted development o, info:eu-repo/semantics/nonPublished

Face-pareidolia is an illusory perception of a face in objects or patterns [1]. Although it is an illusion, it activates brain regions that are typically dedicated to the processing of faces [2]. This study aims to explore how visual context and infants’ visual experience shape the internal representations of these facelike objects. Facelike objects are used here because their ambiguous nature offers many ways to plasticity [3]. We also took advantage of the steady state evoked potentials (SS-EP) technique deriving from electroencephalography (EEG), which principle is based on the fact that the brain synchronizes to any kind of visual information presented in a periodic fashion [4]. SS-EP is particularly suited to test infants because it allows for short and efficient recordings, has an excellent signal-to-noise ratio and is immune to most artifacts [5]. In addition, we conceived an interlaced SS-EP design where 4 to 6 months infants are exposed to 20-second sequences of natural images presented at a rate of 6 images per second (6 Hz). Sequences differ regarding the context in which facelike stimuli are presented: a face context for odd sequences and a house context for even sequences. In this interlaced design, facelike stimuli are also repeated every 5th stimulus, so at the frequency of 1.2 Hz, and faces or houses every 4th stimulus, so at the frequency of 1.5 Hz. When fully collected, infant EEG data will be correlated with indices about their experience with faces collected through Ecological Momentary Assessment (EMA) questionnaires [6]. In a similar experiment with adults, we found that facelike objects generated a significant brain response, which the visual context modulated. In particular, we found that, in adults, the face- and house-context elicited facelike stimuli to be interpreted as objects and faces, respectively. With infants, we rather expect the brain responses to facelike objects to be weaker than in adults because of the protracted development o, info:eu-repo/semantics/nonPublished

Face-pareidolia is an illusory perception of a face in objects or patterns [1]. Although it is an illusion, it activates brain regions that are typically dedicated to the processing of faces [2]. This study aims to explore how visual context and infants’ visual experience shape the internal representations of these facelike objects. Facelike objects are used here because their ambiguous nature offers many ways to plasticity [3]. We also took advantage of the steady state evoked potentials (SS-EP) technique deriving from electroencephalography (EEG), which principle is based on the fact that the brain synchronizes to any kind of visual information presented in a periodic fashion [4]. SS-EP is particularly suited to test infants because it allows for short and efficient recordings, has an excellent signal-to-noise ratio and is immune to most artifacts [5]. In addition, we conceived an interlaced SS-EP design where 4 to 6 months infants are exposed to 20-second sequences of natural images presented at a rate of 6 images per second (6 Hz). Sequences differ regarding the context in which facelike stimuli are presented: a face context for odd sequences and a house context for even sequences. In this interlaced design, facelike stimuli are also repeated every 5th stimulus, so at the frequency of 1.2 Hz, and faces or houses every 4th stimulus, so at the frequency of 1.5 Hz. When fully collected, infant EEG data will be correlated with indices about their experience with faces collected through Ecological Momentary Assessment (EMA) questionnaires [6]. In a similar experiment with adults, we found that facelike objects generated a significant brain response, which the visual context modulated. In particular, we found that, in adults, the face- and house-context elicited facelike stimuli to be interpreted as objects and faces, respectively. With infants, we rather expect the brain responses to facelike objects to be weaker than in adults because of the protracted development o, info:eu-repo/semantics/nonPublished

Snakes and primates have coexisted for thousands of years. Given that snakes are the first of the major primate predators, natural selection may have favored primates whose snake detection abilities allowed for better defensive behavior. Aligning with this idea, we recently provided evidence for an inborn mechanism anchored in the human brain that promptly detects snakes, based on their characteristic visual features. What are the critical visual features driving human neural responses to snakes is an unresolved issue. While their prototypical curvilinear coiled shape seems of major importance, it remains possible that the brain responds to a blend of other visual features. Coloration, in particular, might be of major importance, as it has been shown to act as a powerful aposematic signal. Here, we specifically examine whether color impacts snake-specific responses in the naive, immature infant brain. For this purpose, we recorded the brain activity of 6-to 11-month-old infants using electroencephalography (EEG), while they watched sequences of color or grayscale animal pictures flickering at a periodic rate. We showed that glancing at colored and grayscale snakes generated specific neural responses in the occipital region of the brain. Color did not exert a major influence on the infant brain response but strongly increased the attention devoted to the visual streams. Remarkably, age predicted the strength of the snake-specific response. These results highlight that the expression of the brain-anchored reaction to coiled snakes bears on the refinement of the visual system., SCOPUS: ar.j, info:eu-repo/semantics/published

Throughout the history of man, Aha! or eureka experiences (i.e. the sudden realization of the solution to a vexing problem) have mesmerized scientists and laypeople alike. What makes these sudden, effortless insights so peculiar is their contrast to everyday non-insight problem solving that typically unfolds step-by-step and depends on the exertion of effort. Although there is no doubt that insight feels radically different from non-insight, extant theories are still unable to clarify why insight feels so different than non-insight and whether insight's driving mechanisms are distinct from those underlying non-insight. Generally, it is argued that insight results from a profound shift in how the problem is mentally represented, from a bad to a good problem representation (i.e. restructuring). All of a sudden, the puzzle pieces click together, and the solution pops into the mind. Still, how one reaches this restructuring is still debated. Some argue that restructuring results from unconscious processes triggered by the feeling of being stuck in the solution search (i.e. impasse). Others propose that restructuring is solely or mainly attained by conscious processes honing in on the solution, similar to non-insight processes. From this, it becomes clear that the dissociation between insight and non-insight is crystal clear in certain respects but fuzzy in many others. We conducted four studies to further unravel how insight differs from non-insight on a phenomenological, behavioral, and cognitive dimension. In all studies, participants solved puzzles from the compound remote associates test (CRA) and they classified solved CRA puzzles as being solved with insight or non-insight using self-report. Phenomenologically, our results showed that insight was more often associated with pleasurable feelings (e.g. happiness) and solution certainty than non-insight. Insight solutions also occurred more suddenly and were experienced more intensely than non-insightful ones. Behavio, De mémoire d’homme, scientifiques et autres êtres humains sont intéressés par l’Aha! ou l’expérience Eureka (le moment précis où nous trouvons la solution pour un problème difficile). C’est surtout le contraste avec la manière analytique et graduelle avec laquelle nous solutionnons nos problèmes journaliers qui rendent ces perspicacités remarquables. Malgré qu’il n’y ait aucun doute que la sensation des solutions obtenues par perspicacité est différente de la sensation des solutions obtenues par analyse, les théories existantes ne sont toujours pas aptes à expliquer pour quelle raison cette perspicacité soudaine est ressentie différemment et/ou si les mécanismes profonds sont différents à ceux de l’analyse. En règle générale, on présume que la perspicacité est une conséquence d’une réinterprétation du problème où on passe d’une interprétation erronée à une interprétation correcte. A ce moment tout se met en place et on se rend compte de la solution. Reste la question, d’où vient cette réinterprétation? Certains argumentent que le sentiment d’être dans une impasse génère ce processus inconsciemment. D’autres prétendent qu’elle est due à une recherche continue comme celle inhérente à une analyse. On peut donc déduire que la dissociation entre la perspicacité et l’analyse semble claire dans certains domaines, mais plus troubles dans d’autres. Nous avons mené quatre études afin d’examiner de quelle façon la perspicacité se diffère de l’analyse sur le plan phénoménologique, comportemental et cognitif. Dans toutes les études, les participants ont résolu une série de jeu de mots (compound remote associates test, CRA). Après chaque jeu résolu, le participant indiquait, sur base de son expérience subjective, si la solution provenait d’une analyse ou d’une perspicacité.Sur le plan phénoménologique, la perspicacité était plus souvent associée à des émotions positives (bonheur) et à la confiance en une solution, contrairement à l’analyse. Elle était aussi plus soudaine et resse, Doctorat en Sciences psychologiques et de l'éducation, info:eu-repo/semantics/nonPublished

Face-pareidolia is an illusory perception of a face in objects or patterns. It activates brain regions that are dedicated to the processing of faces (Rekow et al. 2022). This study aims at exploring how infants learn about their surroundings. We operationalize learning through the impact of visual context on how internal representations are shaped. Pareidolia is used because its ambiguous nature offers many ways to plasticity (Gosselin & Schyns, 2003). We also took advantage of the steady state evoked potentials (SS-EP) technique which is particularly suited to test infants because it allows for short and efficient recordings, has an excellent signal-to-noise ratio and is immune to most artifacts (Kabdebon et al. 2022). We conceived an interlaced SS-EP design that we first tested on 20 adults to ensure its applicability with infants. Participants were exposed to two blocks (B1 and B2) of 26 sequences of natural images presented at 6 Hz. Blocks were counterbalanced across participants and differed regarding the context pareidolia was presented in. Pareidolia was repeated every 5th stimulus (1.2 Hz) and faces (B1) or houses (B2) every 4th stimulus (1.5 Hz), which defined the learning context. In adults, pareidolia generated a strong bilateral occipito-temporal brain response, which was modulated by the learning context. In infants, we expect the brain response to be (1) weaker and to activate the right occipito-temporal cortex only (de Heering & Rossion, 2015), and (2) enhanced in the familiar context of faces rather than the unfamiliar one of houses (Rekow et al. 2021)., info:eu-repo/semantics/nonPublished

Face-pareidolia is an illusory perception of a face in objects or patterns. It activates brain regions that are dedicated to the processing of faces (Rekow et al. 2022). This study aims at exploring how infants learn about their surroundings. We operationalize learning through the impact of visual context on how internal representations are shaped. Pareidolia is used because its ambiguous nature offers many ways to plasticity (Gosselin & Schyns, 2003). We also took advantage of the steady state evoked potentials (SS-EP) technique which is particularly suited to test infants because it allows for short and efficient recordings, has an excellent signal-to-noise ratio and is immune to most artifacts (Kabdebon et al. 2022). We conceived an interlaced SS-EP design that we first tested on 20 adults to ensure its applicability with infants. Participants were exposed to two blocks (B1 and B2) of 26 sequences of natural images presented at 6 Hz. Blocks were counterbalanced across participants and differed regarding the context pareidolia was presented in. Pareidolia was repeated every 5th stimulus (1.2 Hz) and faces (B1) or houses (B2) every 4th stimulus (1.5 Hz), which defined the learning context. In adults, pareidolia generated a strong bilateral occipito-temporal brain response, which was modulated by the learning context. In infants, we expect the brain response to be (1) weaker and to activate the right occipito-temporal cortex only (de Heering & Rossion, 2015), and (2) enhanced in the familiar context of faces rather than the unfamiliar one of houses (Rekow et al. 2021)., info:eu-repo/semantics/nonPublished

Face-pareidolia is an illusory perception of a face in objects or patterns. It activates brain regions that are dedicated to the processing of faces (Rekow et al. 2022). This study aims at exploring how infants learn about their surroundings. We operationalize learning through the impact of visual context on how internal representations are shaped. Pareidolia is used because its ambiguous nature offers many ways to plasticity (Gosselin & Schyns, 2003). We also took advantage of the steady state evoked potentials (SS-EP) technique which is particularly suited to test infants because it allows for short and efficient recordings, has an excellent signal-to-noise ratio and is immune to most artifacts (Kabdebon et al. 2022). We conceived an interlaced SS-EP design that we first tested on 20 adults to ensure its applicability with infants. Participants were exposed to two blocks (B1 and B2) of 26 sequences of natural images presented at 6 Hz. Blocks were counterbalanced across participants and differed regarding the context pareidolia was presented in. Pareidolia was repeated every 5th stimulus (1.2 Hz) and faces (B1) or houses (B2) every 4th stimulus (1.5 Hz), which defined the learning context. In adults, pareidolia generated a strong bilateral occipito-temporal brain response, which was modulated by the learning context. In infants, we expect the brain response to be (1) weaker and to activate the right occipito-temporal cortex only (de Heering & Rossion, 2015), and (2) enhanced in the familiar context of faces rather than the unfamiliar one of houses (Rekow et al. 2021)., info:eu-repo/semantics/nonPublished

info:eu-repo/semantics/published

info:eu-repo/semantics/published

info:eu-repo/semantics/published