Glossary of Acronyms and Abbreviations

AVW Analyze file format
BET Brain Extraction Tool - segments brain from non-brain in structural and functional data
COPE Contrast of Parameter Estimates
DOF Degrees Of Freedom, the number of independent pieces of information that go into the estimate of a parameter
EV Explanatory Variable, an effect (e.g. type of stimulation, confound) that is included in a general linear model
FAST FMRIB's Automated Segmentation Tool - brain segmentation (into different tissue types) and bias field correction
FE Fixed Effects. FE variance is the within-session across-time variances estimated in first-level analyses
FEAT FMRI Expert Analysis Tool - for preprocessing and statistical analysis of FMRI data
FILM FMRIB's Improved Linear Model - for GLM-based analysis of first level (time series) data with prewhitening
FIR Finite Impulse Response, a discrete, fixed duration resonse to an impulse
FLAME FMRIB's Local Analysis of Mixed Effects - for higher level analyses of multiple subjects/sessions
FLIRT FMRIB's Linear Image Registration Tool - linear inter- and intra-modal registration
FMRIB Oxford Centre for Functional Magnetic Resonance Imaging of the Brain
FSL FMRIB Software Library - a collection of functional and structural brain image analysis tools
FUGUE FMRIB's Utility for Geometrically Unwarping EPIs - Unwarps geometric distortion in EPI images using B0 field maps
FWHM Full Width between Half Maximum values of a function
GLM General Linear Model (more properly referred to as just "linear model")
GRF Gaussian Random Field. GRF theory is used in various thresholding techniques
GUI Graphical User Interface - lets users interact with tools using a "point and click" approach rather than typing text into a command line.
HRF Haemodynamic Response Function, describes the delayed, blurred haemodynamic response that occurs in response to a stimulus
ICA Independent Component Analysis
MCFLIRT Motion Correction using FMRIB's Linear Image Registration Tool
MCMC Markov Chain Monte Carlo, a sampling technique
ME Mixed Effects. ME variance is the sum of "fixed-effects" variance and "random-effects" variance
MELODIC Multivariate Exploratory Linear Optimized Decomposition into Independent Components - PICA-based model-free analysis of FMRI data
MNI Montreal Neurological Institute. The MNI152 template is a standard-space average of 152 brains
OLS Ordinary Least Squares, a technique for calculating the parameters in a regression equation that minimizes the sum of the squares of the error terms
PE Parameter Estimate, an estimate of how strongly an EV fits the data at each voxel
PICA Probabilistic Independent Component Analysis
RE Random Effects. RE variance is the "true" cross-session variances of first-level parameter estimates
SIENA Structural brain change analysis - for estimating brain atrophy (stands for: Structural Image Evaluation, using Normalisation, of Atrophy)
SUSAN nonlinear noise reduction (stands for: Smallest Univalue Segment Assimilating Nucleus)
TBSS Tract-Based Spatial Statistics - a method for carrying out voxelwise comparisons of diffusion data across subjects
TR Repetition Time - time between scanning succesive brain volumes