Magnetic Resonance Imaging of Brain Function

Abstract

Publisher Summary This chapter describes the magnetic resonance imaging (MRI) of the brain function. The rapid development of methods for noninvasive brain mapping has led to exciting advances in understanding of the human brain. Functional MRI relies on detecting the small changes in image brightness on MRI scans, associated with the hemodynamic changes in the brain, in response to a specific external stimulus or internal cognitive process. Carrying out an fMRI experiment, therefore, consists of three primary components, including presenting or otherwise cueing the stimulus, scanning the brain rapidly using MRI, and analyzing the MRI scans to detect changes in image intensity. The complex physiological processes that give rise to the signal changes observed in fMRI mean that there are a number of reasons for caution in interpreting the experimental results. The most common fast imaging method used for fMRI is echo planar imaging. This method is able to collect data from a single slice through the brain in less than 100 ms. It is found that functional MRI has been used to demonstrate the cortical changes that occur upon rehabilitation after stoke.