61

Since Luria’s initial observations, the cerebral localization of executive processes has been a key point of research in cognitive neuroscience. At first, studies of brain damaged patients showed the main involvement of frontal areas. However, with the emergence of modern neuroimaging tools (positron emission tomography [PET] and functional magnetic resonance imaging [fMRI]), it became obvious that the frontal cortex was not the only region involved in executive functioning but that these processes in fact depended on a large network of distributed antero-posterior areas. From that moment on, researchers became interested in delineating the exact function of the areas associated with various executive processes (updating, shifting, inhibition. . . ), and also in determining the relative importance of anterior and posterior brain areas for executive abilities. Recently, the understanding of areas associated with executive processes as a network of functionally interconnected areas has emerged, as well as the influence of the structural aspects (volume and density of grey and white substance) and genetic characteristics. As a whole, results of these various pieces of research emphasize the interactive and modulatory aspects of executive functioning at the brain level, and the necessity of simultaneously taking into account several levels of analyses. In this review, we will tackle all these questions, focusing mainly on data obtained in young healthy populations for the sake of conciseness.