Investigating Effective Connectivity in Auditory-Motor fMRI Using Granger Causality Analysis

Abstract

Recently medical imaging studies often search for brain and nerve activity such as functional magnetic resonance imaging (fMRI) FMRI is not only capable of observing changes in cerebral blood oxygenation but also of higher spatial resolution In this study we would like to explore effect connectivity among brain regions in auditory-motor experiment using conditional Granger causality analysis which is one statistical test method to analysis temporal causal correlation between fMRI time series In addition we discovered that several factors may affect the results of causal analysis such as the utilization of filter and the selection of repetition time (TR) Thus the appropriate factors are selected in conditional Granger causality analysis by the conclusion of simulations The results show the outflows from auditory cortex are highly detectable in auditory-motor experiment In addition it is shown that time series acquired with short TR without filtering present higher reproducibility in effective connectivity among brain cognitive regions

Date of Award	2014 Jan 21
Original language	English
Supervisor	Ming-Long Wu (Supervisor)