bioRxiv preprint doi: https://doi.org/10.1101/272302; this version posted February 26, 2018. The copyright holder for this preprint (which was not certified by peer review) is the author/funder. All rights reserved. No reuse allowed without permission. Smith et al. Spatial Normalization Revisited 1 The Impact of Spatial Normalization for Functional Magnetic Resonance Imaging Data Analyses Revisited Jason F. Smith1 Juyoen Hur1 Claire M. Kaplan1 Alexander J. Shackman1,2,3 1Department of Psychology, 2Neuroscience and Cognitive Science Program, and 3Maryland Neuroimaging Center, University of Maryland, College Park, MD 20742 USA. Figures: 3 Tables: 4 Supplementary Materials: Supplementary Results Keywords: alignment, functional magnetic resonance imaging (fMRI) methodology, registration, spatial normalization Address Correspondence to: Jason F. Smith (
[email protected]) or Alexander J. Shackman (
[email protected]) Biology-Psychology Building University of Maryland College Park MD 20742 USA bioRxiv preprint doi: https://doi.org/10.1101/272302; this version posted February 26, 2018. The copyright holder for this preprint (which was not certified by peer review) is the author/funder. All rights reserved. No reuse allowed without permission. Smith et al. Spatial Normalization Revisited 2 ABSTRACT Spatial normalization—the process of aligning anatomical or functional data acquired from different individuals to a common stereotaxic atlas—is routinely used in the vast majority of functional neuroimaging studies, with important consequences for scientific inference and reproducibility. Although several approaches exist, multi-step techniques that leverage the superior contrast and spatial resolution afforded by T1-weighted anatomical images to normalize echo planar imaging (EPI) functional data acquired from the same individuals (T1EPI) is now standard.