Brain Functional Network Analysis And Its Applications In Pathophysiology Of Epilepsy With Functional MRI

Functional magnetic resonance imaging (fMRI) is a new technology which can be used to explore functional activities of brain. It is non-invasive and non-radialized technology with high temporal and spatial resolution and can be operated repeatedly. fMRI has become an important tool to do researches on brain and life sciences.Functional segregation and functional integration are two major organizational principles of the human brain functions. The brain always functions as a complicated integrative network. Therefore, it is necessary to explore the human brain from a view of network. More and more resting-state fMRI studies have been carried out recently. These studies investigated the synchrony of low frequency fluctuations (LFF) of blood-oxygen level dependent (BOLD) signals.The aims of the dissertation are to investigate the human brain functional network by using resting-state fMRI, and to explore the alterations of the brain functional network under the pathophysiology of epilepsy. The contents and innovations of these studies are as follows: 1. A new method was proposed for functional connectivity detection using regression analysis. By the application of the method in simulation data and fMRI data, it showed the validity and reliability of the presented method. 2. By using the analysis of functional connectivity, the intrinsic networks of human brains were identified in normal subjects. The study further supported the existence of default mode networks in normal subjects. 3. For the first time, the posterior cingulate cortex (PCC) functional connectivity pattern were analyzed in temporal lobe epilepsy (TLE) patients by using resting-state fMRI. Compared to normal controls, it found that the hippocampus, temporal pole, frontal lobe, temporal lobe, thalamus and precuneus exhibited more significant functional connectivity with the PCC in TLE. The results indicated that the default mode networks were abnormal and suggested that the intrinsic organization of the brain function might be disrupted in TLE. The findings may give deep understanding of the pathogenesis of some clinical symptoms in patients with epilepsy and may give help to the diagnosis and therapy of epilepsy in the future.