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Visual categorization improves when object-context associations in scenes are semantically consistent, thus predictable from schemas stored in long-term memory. However, it is unclear whether this is due to differences in early perceptual processing, in matching of memory representations or in later stages of response selection. We tested these three concurrent explanations across five experiments. At each trial, participants had to categorize a scene context and an object briefly presented within the same image (Experiment 1), or separately in simultaneous images (Experiments 2–5). We analyzed unilateral (Experiments 1, 3) and bilateral presentations (Experiments 2, 4, 5), and presentations on the screen’s horizontal midline (Experiments 1–2) and in the upper and lower visual fields (Experiments 3, 4). In all the experiments, we found a semantic consistency advantage for both context categorization and object categorization. This shows that the memory for object-context semantic associations is activated regardless of whether these two scene components are integrated in the same percept. Our study suggests that the facilitation effect of semantic consistency on categorization occurs at the stage of matching the percept with previous knowledge, supporting the object selection account and extending this framework to an object-context reciprocal influence on matching processes (object-context selection account).

International audience; Only 400 km off the coast of East Africa, the island of Madagascar is one of the last large land masses to have been colonized by humans. While many questions surround the human occupation of Madagascar, recent studies raise the question of human impact on endemic biodiversity and landscape transformation. Previous genetic and linguistic analyses have shown that the Malagasy population has emerged from an admixture that happened during the last millennium, between Bantu-speaking African populations and Austronesianspeaking Asian populations. By studying the sharing of chromosome segments between individuals (IBD determination), local ancestry information and simulated genetic data, we inferred that the Malagasy ancestral Asian population was isolated for more than 1000 years with an effective size of just a few hundred individuals. This isolation ended around 1000 years before present (BP) by admixture with a small African population. Around the admixture time, there was a rapid demographic expansion due to intrinsic population growth of the newly admixed population, which coincides with extensive changes in Madagascar’s landscape and the extinction of all endemic large-bodied vertebrates. Therefore, our approach can provide new insights into past human demography and associated impacts on ecosystems

"Impairments in emotional information processing are frequently reported in attention deficit hyperactivity disorder (ADHD) at a voluntary, explicit level (e.g., emotion recognition) and at an involuntary, implicit level (e.g., emotional interference). Most of previous studies have used faces with emotional expressions, rarely examining other important sources of information usually co-occurring with faces in our every day experience. Here, we examined how the emotional content of an entire visual scene depicting real-world environments and situations is processed in ADHD. We systematically reviewed in PubMed, SCOPUS and ScienceDirect, using the PRISMA guidelines, empirical studies published in English until March 2019, about processing of visual scenes, with or without emotional content, in children and adolescents with ADHD. We included 17 studies among the 154 initially identified. Fifteen used scenes with emotional content (which was task-relevant in seven and irrelevant in eight studies) and two used scenes without emotional content. Even though the interpretation of the results differed according to the theoretical model of emotions of the study and the presence of comorbidity, differences in scene information processing between ADHD and typically developing children and adolescents were reported in all but one study. ADHD children and adolescents show difficulties in the processing of emotional information conveyed by visual scenes, which may stem from a stronger bottom-up impact of emotional stimuli in ADHD, increasing the emotional experience, and from core deficits of the disorder, decreasing the overall processing of the scene".