Cognitive control and binding in context-based decision-making
On Thursday 3 December, 2009, Nelleke van Wouwe defended her thesis 'Cognitive Control and Binding in Context-based Decision-making.
Before switching to Psychology in Leiden, Nelleke van Wouwe first studied at the Design Academy at Eindhoven for 2 years. She graduated in Cognitive Psychology (specialization Neuropsychology) and worked a PhD student on cognitive control, context processing and dopamine. Part of the dissertation work was performed at the University Medical Centre of Charlottesville (US, Virginia) were she investigated Parkinson’s patients. She has defended her dissertation on the 3rd of December. Since June she works as a research employee with TNO Defence, Safety and Security at the department of Human Performance.
Part of van Wouwe’s research concerned the role of dopamine and the basal ganglia (a structure in the midbrain) in decision making and learning. In Parkinson’s patients dopamine is severely reduced in the basal ganglia, which causes movement and cognitive disabilities. She investigated the effect of dopaminergic medication and deep brain stimulation on the learning abilities of Parkinson’s patients. Deep brain stimulation is a relatively new treatment; with this treatment electrodes are implanted in the patients’ brain and continuously electrically stimulate a specific area of the basal ganglia. This reduces the patients’ movement problems, but the cognitive effects are still unclear. Thus this study served both a fundamental and a more clinical purpose. Both patient groups performed a learning task on an off stimulation or medication. During the learning task patients were instructed to try to gain money by learning relations between pictures and a left or right hand response which they were rewarded for. Deep brain stimulation and medication both improved learning relations between stimuli and actions based on feedback, but the learning effect was more impressive in the patients treated by deep brain stimulation.
Van Wouwe especially enjoyed her stay in the U.S. because it provided her with some experience on working in a different research environment. Working with American subjects was a lot of fun and supplied her with some interesting stories; for example some of her subjects thought that since World War II the Dutch spoke German. Another subjects’ medication was not entirely stable; this person asked her to hit him hard. Obviously she could not fulfill this request, since it was not part of her research. Overall, she liked working on studies that contribute to both clinical as well as more fundamental knowledge of the brain and she hopes to continue with similar studies in the future.