The topic of the methods course for students of the "MSc (Master in Neurosciences) study program" and the "IMPRS (International Max Planck Research School) Neurosciences" is to learn the intracellular recording of neuronal signals from single neurons. The medical leech (Hirudo medicinalis) serves as a model organism, since its neurons are easy to infer even for beginners due to their size and visibility. XLAB lecturer Michael Ferber PhD regularly teaches this basic technique.