Material and Methods

Subjects

Two datasets were used in this project; a control set consisting of 10 healthy patients with no known neurological diseases and a test set consisting of 10 patients in a coma state who had suffered from traumatic brain injury. The EEG data used in this project were provided by Dr. Shinung Ching and was retrospectively collected from 20 patients who underwent EEG for routine monitoring purposed related to a diagnosis of coma or less-severe DLOC. DLOC was assessed using the Glasgow Coma Scale (GCD) ≤ 0 at the time of EEG, in the Neurological and Neurosurgical Intensive Care Unit at Barnes-Jewish Hospital and Washington University School of Medicine. For each case, EEG was carried out to detect non-convulsive seizures in patients with otherwise inadequately explained DLOC, and the cases in which seizures were not detected at any point in the hospitalization were analyzed. It is important to note that the assessments of the individual coma patients’ focal or diffuse classification using diagnostic data was not provided in the data sets used for analysis. Since severity and localization of the brain injury of each test patient was not provided, we sought to make conclusions on the overall effects of traumatic brain injury on brain network dynamics. Upon completion of Human Subject Training through the Collaborative Institutional Training Initiative (CITI), we satisfied the educational requirements necessary to conduct human subject research at Washington University.