Mental disorders are a major health problem with a lifetime prevalence of more than 25% (WHO report 2001). According to the WHO, 25% of the general population will have one or more mental disorders during their lifetime: this is a major health problem. In Europe, 34 million people in 2004 had addiction, affective, and anxiety disorders, costing society 204 billion Euros.

The use of brain imaging methods, such as Magnetic Resonance Imaging (MRI), makes it possible to understand brain mechanisms that underlie personality traits and disorders. Furthermore, we can link them to genetic variation and behavioural changes that are characteristic of disease processes.

Recent advances in genomics (the study of genes and their functions) provide new opportunities to identify genes that influence these processes, and to examine their interaction with environmental factors.

One of the major challenges addressed in this project is to assemble key biological resources and brain imaging data from human volunteers as well as animal models to understand what underlies individual behavioural differences.

The goals of assembling and investigating these materials can be achieved only through a large, inter-disciplinary collaboration that integrates groups specialised in brain imaging, human genetics and behaviour.

Why study adolescents?

75% of mental disorders appear before the age of 25. We know significant brain development takes place during adolescence. Developmental processes during adolescence are crucial for the establishment of behaviours including sensitivity to reward and punishment, impulsivity and emotional responses. These behaviours are important elements in mental disorders. Because this is such an important developmental period, factors including drug-use and stress may result in an increased risk of mental illness. The IMAGEN project aims to understand the consequences of stressors on the brain and behaviour in order to better predict the risk of mental illness and to improve treatment.