title: Statistical improvements in functional magnetic resonance imaging analyses produced by censoring high-motion data points.
abstract: Subject motion degrades the quality of task functional magnetic resonance imaging (fMRI) data. Here, we test two classes of methods to counteract the effects of motion in task fMRI data: (1) a variety of motion regressions and (2) motion censoring ("motion scrubbing"). In motion regression, various regressors based on realignment estimates were included as nuisance regressors in general linear model (GLM) estimation. In motion censoring, volumes in which head motion exceeded a threshold were withheld from GLM estimation. The effects of each method were explored in several task fMRI data sets and compared using indicators of data quality and signal-to-noise ratio. Motion censoring decreased variance in parameter estimates within- and across-subjects, reduced residual error in GLM estimation, and increased the magnitude of statistical effects. Motion censoring performed better than all forms of motion regression and also performed well across a variety of parameter spaces, in GLMs with assumed or unassumed response shapes. We conclude that motion censoring improves the quality of task fMRI data and can be a valuable processing step in studies involving populations with even mild amounts of head movement.
authors.affiliation: Department of Neurology, Washington University School of Medicine, St. Louis, Missouri.
authors.forename: Joshua S
authors.initials: JS
authors.lastname: Siegel
authors.forename: Jonathan D
authors.initials: JD
authors.lastname: Power
authors.forename: Joseph W
authors.initials: JW
authors.lastname: Dubis
authors.forename: Alecia C
authors.initials: AC
authors.lastname: Vogel
authors.forename: Jessica A
authors.initials: JA
authors.lastname: Church
authors.forename: Bradley L
authors.initials: BL
authors.lastname: Schlaggar
authors.forename: Steven E
authors.initials: SE
authors.lastname: Petersen
mesh_terms: D000293:Adolescent; D000328:Adult; D000465:Algorithms; D001921:Brain / Q000098:blood supply* / Q000502:physiology*; D002648:Child; D002657:Child Development / Q000502:physiology*; D015331:Cohort Studies; D005260:Female; D019416:Head Movements / Q000502:physiology*; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging; D008297:Male; D009038:Motion; D010100:Oxygen / Q000097:blood; D012044:Regression Analysis; D012684:Sensory Thresholds / Q000502:physiology; D055815:Young Adult
chemical_list: D010100:Oxygen
keywords: GLM; data quality; fMRI; general linear model; head movement; motion; noise; scrubbing; task