All patients underwent STN electrode implantation for DBS treatment of Parkinson’s disease at the National Hospital of Neurology and Neurosurgery (University College London) or the John Radcliffe Hospital (University of Oxford) between 2007 and 2014. Ethical approval was obtained from the local ethics committees at University College London and University of Oxford, and 33 subjects gave written informed consent to the study, and were recorded. All were diagnosed with Parkinson’s disease according to the Queen Square Brain Bank Criteria (Gibb and Lees, 1988). Motor impairments of each patient were evaluated on average approximately 5 months prior to surgery using part III of the UPDRS after omitting all dopaminergic medication overnight, and following administration of at least 200 mg of levodopa. For detailed patient characteristics see Supplementary Table S1. Data from a subset of these patients have been described in earlier publications (Litvak et al., 2011a, Litvak et al., 2012, Oswal et al., 2013a).
