The PICOWO research group in corporation with the University of Amsterdam (Artificial Intelligence) has developed a computer simulationmodel of eating disorders (Bosse, Delfos, Jonker & Treur, 2003). In a running Phd project we want to add ghrelin to the model. The idea for this current research is to collect clinical information about the functioning and (patho)physiology of ghrelin in patients with AN, so we can extend the simulation.