Overview of fMRI analysis
© Oxford University Press 2001. All rights reserved. This chapter gives an overview of the various analysis steps that are required after a functional magnetic resonance imaging (fMRI) experiment has been designed and carried out. The resulting data must be passed through various analysis steps before the experimenter can get answers to questions about experimentally related activations at the individual or multi-subject level. The aim of fMRI analysis is to identify in which voxels' time-series the signal of interest is significantly greater than the noise level. The chapter also provides a brief overview of different approaches to obtaining activation maps, followed by a detailed introduction to analysis via the general linear model - currently the most popular statistical approach - and also various methods of thresholding the resulting statistics maps. It describes briefly the practical and numerical details involved in the analysis of a particular fMRI experiment.