Neurotransmitters & networks: an MR view on epilepsy and antiepileptic drugs

The aim of this dissertation is to study the relationship between brain connectivity and cognitive problems resulting from epilepsy and antiepileptic drug use as well as the techniques used to examine this. Brain networks are studied by means of functional magnetic resonance imaging (fMRI). Neurotransmitters, which are important messengers that coordinate communication within the networks, are studied by means of magnetic resonance spectroscopy (MRS). It is shown that the neurotransmitter levels measured are associated with antiepileptic drug use and cognition. The best technique to measure these levels is assessed. In addition, a new analysis method for measuring brain networks is developed based on neurotransmitter levels measured by 7T MRI. These networks are shown to be abnormal in patients with epilepsy. The results of this dissertation contribute to a better understanding of cognitive side effects of antiepileptic drug use. They also provide information which can be helpful in further exploring this relationship, allowing treatment strategies for patients with epilepsy to be improved.