https://onlinelibrary.wiley.com/doi/epdf/10.1002/ana.23951?src=getftr#:~:text=We%20recorded%208,74%2C%20No.%203 We recorded 8 patients (Table 1) with advanced idiopathic PD with motor fluctuations and/or dyskinesias who gave their informed consent to take part in the study, which was approved by the National Research Ethics Service Committee South Central–Oxford A. Patients underwent DBS surgery on the STN as previously described.10 In Cases 2, 7, and 8 (see Table 1), the locations of the electrodes were confirmed with immediate postoperative fast spin-echo T2-weighted magnetic resonance imaging (MRI) with a Leksell frame still in situ. In the remaining cases, locations were confirmed with immediate postoperative computed tomography (CT) with a Leksell or CRW frame (Integra Radionics, Burlington, MA) still in situ. CT scans were then fused with preoperative T2-weighted MRI.11 Electrode extension cables were externalized through the scalp to enable recordings prior to connection to a subcutaneous DBS pacemaker, implanted in a second operative procedure up to 7 days later. The permanent quadripolar macroelectrode used was model 3389 (Medtronic Neurologic Division, Minneapolis, MN), featuring 4 platinum–iridium cylindrical surfaces. Its contacts are numbered 0, 1, 2, and 3, with 0 being the most caudal and contact 3 being the most cranial