Professor John Axelsson leads research groups at the Stress Research Institute, Stockholm University, and at Karolinska Institutet. With his research he aims to increase the knowledge and awareness of how we sleep in the rapidly developing 24 hour society, and its importance for health, cognitive processes and social behaviour. Two of the research questions we finds most intriguing concern how fast the brain can switch from sleep to wakefulness and why individuals are so differently affected by sleep loss.