Variability in fMRI: a re-examination of inter-session differences.

Oxford Centre for Functional Magnetic Resonance Imaging of the Brain (FMRIB), Department of Clinical Neurology, Oxford University, John Radcliffe Hospital, Headington, Oxford, United Kingdom.
Human Brain Mapping (Impact Factor: 6.92). 04/2005; 24(3):248-57. DOI: 10.1002/hbm.20080
Source: PubMed

ABSTRACT We revisit a previous study on inter-session variability (McGonigle et al. [2000]: Neuroimage 11:708-734), showing that contrary to one popular interpretation of the original article, inter-session variability is not necessarily high. We also highlight how evaluating variability based on thresholded single-session images alone can be misleading. Finally, we show that the use of different first-level preprocessing, time-series statistics, and registration analysis methodologies can give significantly different inter-session analysis results.

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May 29, 2014

Narender Ramnani