Effects of dopaminergic drugs on cognition
Patients with neurological diseases often have difficulty in evaluating, planning and initiating actions. This can lead to disorders of motivation, such as apathy and impulsivity. My group studies the cognitive neuroscience of goal-directed action, in the context of disease. Some patients have difficulty evaluating a particular plan in a given context. For example, they might revert to habitual actions which were previously associated with reward, or may be unable to think beyond their current situation. We take a multimodal approach, with behavioural studies, eye tracking, drug studies in healthy people and patients, EEG and neuroimaging. I have also developed computational models – both in the form of abstract cognitive models, and neural network simulations, to understand what the brain computes when determining actions.
My group has found that dopamine plays an important role in energising goal-appropriate actions. We hypothesise that prefrontal goal representations act through corticostriatal loops, being amplified or attenuated by dopamine. In this project, the student will study patients with Parkinson’s disease and the effects of dopaminergic drugs on cognition, together with neuroimaging (which can include MEG or fMRI), to understand goal-directed action selection and energisation. The student will design their own behavioural tasks to separate out the component processes involved in maintaining and using goal information to energise actions. The student will test patients on their task, test drug mechanisms using a within-subject neuroimaging design, and deploy appropriate analysis methods with help from a postdoctoral researcher. The project will also include the opportunity to learn computational modelling if the student is keen.