The main objective of the study is to examine the same effects of the COMT genotype on problem solving and the frontoparietal network activity in a normal healthy volunteers. These healthy volunteers will be age matched with our previously acquired Parkinsons data. Each volunteer will take part in one fMRI scanning session, at the MRC Cognition & Brain Sciences Unit, during which they will undertake a 10 minute planning task, and a twenty minute cognitive flexibility task, as well as standard structural scans. In addition volunteers will undertake a short battery of standard cognitive tests from the CANTAB testing battery. Testing will take in total approximately 2 hours, with no more than 1 hour 15 minutes spent in the scanner. As a number of age matched controls have already taken part in the study, we will require details of only 20 participants of each COMT genotype.
