I am interested in understanding how symptoms emerge from circuit dysfunction in movement disorders. Addressing this question motivates me because it may contribute to the improvement or development of targeted therapies, but also because this knowledge may provide crucial insights into how the brain controls movement. In accordance, I focused my PhD work on understanding the role of substantia nigra pars compacta (SNc) dopamine neurons in action initiation, given the impairments in movement initiation when these neurons are lost in Parkinson’s disease. Using a combination of electrophysiology recordings, calcium imaging and optogenetic manipulations of genetically identified SNc dopamine neurons, we discovered that the activity of these neurons gates and invigorates movement initiation. Furthermore, I pioneered the use of inertial sensors in rodents to precisely define movement initiation with millisecond resolution, a technology that we have been exploring and refining further in our group as a novel phenotyping tool for movement disorder animal models. I have recently started an independent position as a group leader. Our group uses genetic, optical and electrophysiological methods, combined with state-of-the-art behavior analysis, to study the dysfunction of neural circuits associated with movement disorders.