In its research into the neurobiological causes of psychiatric disorders, the Animal Physiology Group works with two complementary model systems. Mice have the advantage that they allow direct experimental access to all levels of neuronal organization (synapses, cells, circuits, behavior) within the same individual in order to establish a direct link between molecular/genetic pathology, neurobiological dysfunction and behavioral disorders. Alternatively, we use human nerve cell cultures from induced pluripotent stem cells (iPS cells). This allows us to dispense with the use of mice (replacement). We also use iPS cells from patients with psychiatric disorders. These cells have the advantage that they represent the entire genetic complexity of psychiatric disorders. The human iPS cells are obtained from blood cells of patients and healthy volunteers by reprogramming. Using cell biology methods, human nerve cells are cultivated from the iPS cells, which are examined using the same high-resolution electro- and optophysiological methods as mouse cells. Human iPS cells have great potential for use in personalized medicine and for drug screens in the search for new therapies.