A drug like levodopa, which is used by patients with Parkinson's disease, causes changes in the communication between deep brain areas that are important for learning and behaviour. As a result of this, impulse control disorders such as gambling addiction or hypersexuality can occur. PhD researcher Payam Piray demonstrated this during research carried out at the Donders Institute in Nijmegen. He will defend his doctoral thesis on Thursday 1 December 2016. His research was funded with a grant from the NWO Free Competition.