No abstract

Children with attention-deficit/hyperactivity disorder (ADHD) present a deficit in inhibitory control. Still, it remains unclear whether it comes from a deficit in reactive inhibition (ability to stop the action in progress), proactive inhibition (ability to exert preparatory control), or both.We compared the performance of 39 children with ADHD and 42 typically developing children performing a Simon choice reaction time task. The Simon task is a conflict task that is well-adapted to dissociate proactive and reactive inhibition. Beyond classical global measures (mean reaction time, accuracy rate, and interference effect), we used more sophisticated dynamic analyses of the interference effect and accuracy rate to investigate reactive inhibition. We studied proactive inhibition through the congruency sequence effect (CSE).Our results showed that children with ADHD had impaired reactive but not proactive inhibition. Moreover, the deficit found in reactive inhibition seems to be due to both a stronger impulse capture and more difficulties in inhibiting impulsive responses. These findings contribute to a better understanding of how ADHD affects inhibitory control in children.

Objective: A deficit in interference control is commonly reported in children with attention deficit hyperactivity disorder (ADHD). This has mainly been interpreted as a difficulty in inhibiting inappropriate responses. However, it could be due to at least two distinct and independent processes, which are often confounded: the activation or suppression of impulsive responses. The aim of the present study was to separate the contribution of these two processes. Method: We compared performance of 26 children with ADHD to that of 26 non-ADHD children using a novel approach based on electromyographic activity (EMG) analysis. EMG allows two distinct indices to be computed: incorrect activation rate, which is an index of the intensity of impulse capture and correction rate, which provides a direct measure of the ability to suppress automatic responses. Results: Children with ADHD were slower, committed more errors, and had a larger interference effect than non-ADHD children. Moreover, we observed a greater incorrect activation rate and a lower correction rate in the ADHD group. Conclusions: Our data suggest that the difficulties in interference control found in children with ADHD are explained by both impaired inhibitory processes and a greater propensity to activate automatic responses.

Évaluer les impacts des recherches en agriculture sur la société : outils, méthodes, études de cas. Résumé -Les acteurs publics impliqués dans les politiques publiques, situés à plusieurs échelles territoriales, occupent une place non négligeable dans les mécanismes d'innovation. Le cadre d'analyse « chemin de l'impact » aide à caractériser la participation de ces acteurs publics, au côté, en amont ou en aval des chercheurs et d'autres acteurs dans les processus d'impact de la recherche. Ce cadre a été complété par une revue de littérature sur l'impact de la recherche sur les politiques publiques. L'étude transversale d'un panel de cas de recherches agricoles à l'aide d'une même démarche analytique a permis de mieux cerner les rôles de ces acteurs dans la recherche dans les pays en développement. Par des moyens très diversifiés, dans plusieurs cas, les acteurs publics contribuent à rendre possible l'impact de la recherche pour le développement. En symétrie, dans quelques cas, les chercheurs améliorent les capacités des acteurs publics ou les aident à prendre des décisions mieux éclairées et influencent ainsi les politiques publiques. Il convient donc d'encourager les acteurs publics à être plus réceptifs à la recherche et les chercheurs à développer leurs interactions avec les acteurs des politiques publiques. Les connaissances sur le lien recherche-politique doivent être approfondies car elles peuvent aider la recherche à avoir plus d'impact pour le développement.Mots clés : impact de la recherche / politique publique / acteur public / pays en développement Abstract -How public actors contribute to the impact of research in developing countries. Public actors involved in public policies, located across several levels of territories, hold a significant place in innovation mechanisms. The analysis framework of "impact pathway" helps to characterize the involvement of these public actors, together, upstream or downstream of researchers and other actors in the impact of research processes. This framework was complemented by a literature review on the impact of research on public policy. The crosscutting study of a panel of agricultural research cases using the same analytical approach allowed for a better understanding of the roles of public actors in developing countries' research. By very diverse means, public actors contribute to make the impact of research for development possible. In symmetry, in a few cases, researchers improve the capacities of public actors, support them for in policymaking and thus influence public policies. It is necessary to encourage public actors to be more receptive to research; and researchers to develop interactions with policymakers. Knowledge about the research-policy link needs to be deepened as it can help research to have more impact for development.