Electroencephalogram based Causality Graph Analysis in Behavior Tasks of Parkinson’s Disease Patients

Electroencephalographic (EEG) signals of the human brains represent electrical activities for a number of channels recorded over a the scalp. The main purpose of this thesis is to investigate the interactions and causality of different parts of a brain using EEG signals recorded during a performance subjects of verbal fluency tasks. Subjects who have Parkinson's Disease (PD) have difficulties with mental tasks, such as switching between one behavior task and another. The behavior tasks include phonemic fluency, semantic fluency, category semantic fluency and reading fluency. This method uses verbal generation skills, activating different Broca's areas of the Brodmann's areas (BA44 and BA45). Advanced signal processing techniques are used in order to determine the activated frequency bands in the granger causality for verbal fluency tasks. The graph learning technique for channel strength is used to characterize the complex graph of Granger causality. Also, the support vector machine (SVM) method is used for training a classifier between two subjects with PD and two healthy controls. Neural data from the study was recorded at the Colorado Neurological Institute (CNI). The study reveals significant difference between PD subjects and healthy controls in terms of brain connectivities in the Broca's Area BA44 and BA45 corresponding to EEG electrodes. The results in this thesis also demonstrate the possibility to classify based on the flow of information and causality in the brain of verbal fluency tasks. These methods have the potential to be applied in the future to identify pathological information flow and causality of neurological diseases.

Treatment Outcomes for Eating Disorder Patients With and Without Comorbid Substance Abuse Diagnoses

The impact of comorbid substance abuse and eating disorder diagnoses in an eating disorder treatment facility remains uncertain. Recent data suggest that in a substance abuse treatment setting, patients with comorbid eating disorders fared less favorably than patients without a comorbid diagnosis (Cohen et al., 2010; Glasner-Edwards et al., 2011). The purpose of this study is to compare eating disorder symptoms over the course of treatment for patients with and without comorbid substance abuse diagnoses in an eating disorder treatment facility. Archival data from an eating disorder treatment facility was used. Twenty-seven women with comorbid eating disorder and substance abuse diagnoses (EDSUD) were compared to twenty-seven women with an eating disorder diagnosis (ED) only. The subjects were compared on three scales from the Eating Disorder Inventory-III (EDI-3) by group, and pre- and post-treatment. The scales were Personal Alienation (PA), Interoceptive Deficits (ID), and Emotional Dysregulation (EmD). There was a significant decrease in symptoms post-treatment for all subjects on the PA and ID scales, and there was a significant difference between the EDSUD subjects and ED subjects on two scales. EDSUD subjects fared significantly less favorably on the ID and EmD scales. Women with EDSUD report more symptoms of Interoceptive Deficits and Emotional Dysregulation when compared to women with an ED diagnosis and no comorbid substance use. Subjects benefited from treatment in terms of less Personal Alienation and Interoceptive Deficits.