Nadine Katrin Gut is a research associate who has focused on the dissection of neural circuits in the pedunculopontine nucleus (PPN) and related subcortical structures for more than a decade. She started her research career working on translational aspects of PPN deep brain stimulation in rodent models of Parkinson’s disease. Recognizing its limitations due to the lack of understanding of the complexity of the PPN, she applied state-of-the-art techniques during her postdoctoral training to investigate the distinct functional roles of PPN circuits. She discovered a direct, inhibitory input from the PPN to dopamine neurons in the midbrain, which terminates the execution and inhibits the initiation of specific actions, leading to bradykinesia-like behaviors. She also investigated the other main neuronal cell types of the PPN. Her work contributed to the understanding that different circuits formed by different cell types have not only different but also opposite behavioral roles.