Decreased Prefrontal Activity During a Cognitive Inhibition Task Following Violent Video Game Play: A Multi-Week Randomized Trial

There is substantial evidence that exposure to violent media increases aggressive thoughts and behaviors, potentially due in part to alterations to inhibitory mechanisms mediated by prefrontal cortex. Past research has demonstrated that playing a violent video game for short periods decreases subsequent prefrontal activity during inhibition, yet the impact of long-term game play is unclear. To assess how extensive video game play impacts brain activity, young adult males (n = 49; ages 18–29) with limited video game experience performed a go/no-go task during fMRI for 3 consecutive weeks. Following a baseline scan, these men were randomly assigned to extensively play a violent video game (VG) or avoid all video game play (control) during the subsequent week. After 1 week, inhibition-related activity decreased in right inferior frontal gyrus and right cerebellum in the VG group, compared to the control sample, and self-reported executive functioning problems were higher. VG participants assigned to a second week of game play had similarly reduced bilateral prefrontal activity during inhibition, relative to the control group. However, VG participants assigned to avoid game play or play a cognitive training game during the second week demonstrated similar overall changes from baseline as the control group. This research provides preliminary evidence indicating how long-term video game play may impact brain function during inhibition, which may impair control of aggressive behavior

Robust estimation of fractal measures for characterizing the structural complexity of the human brain: optimization and reproducibility

High-resolution isotropic three-dimensional reconstructions of human brain gray and white matter structures can be characterized to quantify aspects of their shape, volume and topological complexity. In particular, methods based on fractal analysis have been applied in neuroimaging studies to quantify the structural complexity of the brain in both healthy and impaired conditions. The usefulness of such measures for characterizing individual differences in brain structure critically depends on their within-subject reproducibility in order to allow the robust detection of between-subject differences. This study analyzes key analytic parameters of three fractal-based methods that rely on the box-counting algorithm with the aim to maximize within-subject reproducibility of the fractal characterizations of different brain objects, including the pial surface, the cortical ribbon volume, the white matter volume and the grey matter/white matter boundary. Two separate datasets originating from different imaging centers were analyzed, comprising, 50 subjects with three and 24 subjects with four successive scanning sessions per subject, respectively. The reproducibility of fractal measures was statistically assessed by computing their intra-class correlations. Results reveal differences between different fractal estimators and allow the identification of several parameters that are critical for high reproducibility. Highest reproducibility with intra-class correlations in the range of 0.9–0.95 is achieved with the correlation dimension. Further analyses of the fractal dimensions of parcellated cortical and subcortical gray matter regions suggest robustly estimated and region-specific patterns of individual variability. These results are valuable for defining appropriate parameter configurations when studying changes in fractal descriptors of human brain structure, for instance in studies of neurological diseases that do not allow repeated measurements or for disease-course longitudinal studies

The EU as black widow; Devouring the WEU to give birth to a European Security and Defence Policy

The Treaty of Nice will finally turn the European Union into a security and defence organisation. Alongside its tasks in all other areas the Union will be given the competence to strengthen its contribution to the maintenance of international peace and security in accordance with the UN Charter. This Chapter deals with the development of a European Security and Defence Policy (ESDP) over the past few years with particular focus on the international legal aspects of the relationship of the EU with the Western European Union (WEU). The EU courted the WEU for ten years. This finally seems to have paid off with the birth of an early and fragile European Security and Defence Policy, albeit at the price of sacrificing the WEU

1983, le tournant médiatique

Ce dossier remonte aux sources de la fabrication du discours médiatique sur l’immigration en France. Dans les médias, l’année 1983 marque un tournant majeur dans la prise en compte et la visibilité des populations immigrées, sous la pression des actes racistes qui se multiplient dans un contexte de crise sociale et économique, de changement de cap politique du gouvernement socialiste et de montée du Front national. C’est aussi l’année où la seconde génération de l’immigration se mobilise à travers la Marche pour l’égalité et contre le racisme. Les articles analysent l’évolution des images stéréotypées sur cette altérité de l’immigration qui va s’instaurer durablement sur les écrans (cinéma, télévision, internet)