Movement disorder patients undergoing intracranial electrode implantation for deep brain stimulation therapy participated in a speech production task (Bush et al., 2021 ), for which the baseline periods were analyzed in this study. One or two high-density subdural electrocorticography (ECoG) strips were temporary placed through the standard burr hole, targeting the left superior temporal gyrus (covering also the ventral sensorimotor cortex) and left inferior frontal gyrus. ECoG electrodes were removed at the end of the surgery. Dopaminergic medication was withdrawn the night before surgery. All procedures were approved by the University of Pittsburgh Institutional Review Board (IRB Protocol #PRO13110420) and all patients provided informed consent to participate in the study. The following cohorts of movement disorder patients participated in the study: 29 Parkinson’s disease patients (21M/8F, 65.6±7.1 years) undergoing awake subthalamic (STN) DBS surgery, all of which had ECoG recordings and 14 of which had simultaneous ECoG and DBS lead recordings; 5 Parkinson’s disease patients (5M/0F, 69.1±5.7 years) undergoing awake pallidal (GPi) DBS surgery, of which 4 had ECoG recordings and 3 had simultaneous ECoG and DBS lead recordings; 22 essential tremor patients (11M/11F, 65.3±9.7 years) undergoing awake thalamic (Vim) DBS surgery, of which 20 had ECoG recordings and 11 had simultaneous ECoG and DBS lead recordings.
Additionally, we analyzed awake restfulness data from 8 epilepsy patients (5M/3F, age: 18±11 years) undergoing stereo-EEG (sEEG) intracranial monitoring for epilepsy with additional electrodes implanted in the thalamus. This study was approved by the Massachusetts General Hospital (Boston, MA) Institutional Review Board (IRB Protocol #2020P000281).