Analysis of large brain MRI databases for investigating the relationships between brain, cognitive, and genetic polymorphisms

A major challenge for the years to come is the understanding of the brain-behaviour relationships, and in particular the investigation and quantification of the impact of genetic polymorphism on these relationships. In this framework, a promising experimental approach, which we will refer to as neuro-epidemiologic imaging, consists in acquiring multimodal (brain images, psychometric an d sociological data, genotypes) data in large (several hundreds or thousands ) cohorts of subjects. Processing of such large databases requires on first place the conception and implementation of automated 'pipelines', including image registration, spatial normalisation tissue segmentation, and multivariate statistical analysis. Given the number of images and data to be processed, such pipelines must be both fully automated and robust enough to be able to handle multi-center MRI data, e.g. having inhomogeneous characteristics in terms of resolution and contrast. This approach will be illustrated using two databases collected in aged healthy subjects, searching for the impact of genetic and environmental on two markers of brain aging, namely white matter hyper-signals, and grey matter atrophy. (author)