Medicine and Health Sciences Commons^™

Inter-Subject Correlation Using Movie-Driven Fmri In Drug-Resistant Epilepsy, Hana H. Abbas

Electronic Thesis and Dissertation Repository

Treating drug-resistant epilepsy with surgery requires the localization of the epileptic focus. We explored the potential for movie-driven functional magnetic resonance imaging (fMRI) to act as a sensitive, non-invasive, and cost-effective tool to identify functionally disturbed networks. We assessed neural synchronization (inter-subject correlation; ISC) between presurgical epilepsy patients (n = 18) and healthy controls (n = 24) as they watched a suspenseful movie clip in the scanner. To optimize denoising, we compared ISC values with and without an automated Independent Components Analysis-based denoising step (ICA-AROMA). We found that denoising with ICA-AROMA elicited augmented correlation values, supporting its use …

Neurocircuits Of Posttraumatic Stress Disorder And Its Dissociative Subtype, Andrew A. Nicholson

Electronic Thesis and Dissertation Repository

The amygdala and insula are highly implicated in the pathophysiology of posttraumatic stress disorder (PTSD), where both have been shown to be hyper/hypoactive in PTSD and dissociative subtype (PTSD+DS) PTSD patients, respectively, during symptom provocation. However, the functional connectivity of individual amygdala and insula subregions have not previously been compared in PTSD, PTSD+DS and healthy controls. In two separate studies, we examined amygdala complex (chapter 2) and insula subregion (chapter 3) functional connectivity patterns using resting-state fMRI. Patients with PTSD and PTSD+DS were found to display unique amygdala complex functional connectivity patterns to prefrontal cortex (PFC) regions involved in emotion …

Seeing With Sound: Investigating The Behavioural Applications And Neural Correlates Of Human Echolocation, Jennifer L. Milne

Electronic Thesis and Dissertation Repository

Some blind humans use the reflected echoes from self-produced signals to perceive their silent surroundings. Although the use of echolocation is well documented in animals such as bats and dolphins, comparatively little is known about human echolocation. The overarching goal of the work presented in this thesis was to shed light on some of the basic functions of human echolocation, including the perception of the shape, size, and material. I addressed these aspects of echolocation using behavioural psychophysics and neuroimaging.

In Chapter 2 I show that blind echolocators were able to accurately identify the shape of 2D objects, but that …