Trust is important for successful social interactions. This program investigates how trust between people develops, focusing on the behavioural and neural mechanisms. We are also interested in why trust is disturbed in some psychiatric disorders, for example in paranoid delusions, one of the core symptoms of a psychotic disorder. This research was made possible by a VIDI grant from NWO in 2007 and the award of a grant from the Dutch Brain Foundation in 2011.
To study trust in a lab situation we use the so-called trust game. This game involves investment decisions with an anonymous other player. The game is programmed such that trusting each other yields the highest reward for both players. However, if the other player does not return the investment, the first player faces a loss. The amount the first player invests, can therefore be seen as a measure of trust. The game can also be played inside an fMRI scanner, which allows measuring the brain activation during investment decisions.
The study includes patients with a psychotic disorder, first-degree relatives of these patients, people with ultra-high risk of psychosis, and healthy subjects. Both adolescents and adults participate, so that we can also investigate the development of trust. The results show that patients with a psychotic disorder invest less, in other words, shows less trust in the anonymous partner, than healthy controls. Patients also respond less strongly to information that the anonymous partner is trustworthy. The comparison between adolescents and adults showed that trust, as measured by the trust game, increases with age and that this is associated with changes in brain areas that are part of the 'social brain'.
Get to know the team performing this study.