title: Motion-related artifacts in structural brain images revealed with independent estimates of in-scanner head motion.
abstract: Motion-contaminated T1-weighted (T1w) magnetic resonance imaging (MRI) results in misestimates of brain structure. Because conventional T1w scans are not collected with direct measures of head motion, a practical alternative is needed to identify potential motion-induced bias in measures of brain anatomy. Head movements during functional MRI (fMRI) scanning of 266 healthy adults (20-89 years) were analyzed to reveal stable features of in-scanner head motion. The magnitude of head motion increased with age and exhibited within-participant stability across different fMRI scans. fMRI head motion was then related to measurements of both quality control (QC) and brain anatomy derived from a T1w structural image from the same scan session. A procedure was adopted to "flag" individuals exhibiting excessive head movement during fMRI or poor T1w quality rating. The flagging procedure reliably reduced the influence of head motion on estimates of gray matter thickness across the cortical surface. Moreover, T1w images from flagged participants exhibited reduced estimates of gray matter thickness and volume in comparison to age- and gender-matched samples, resulting in inflated effect sizes in the relationships between regional anatomical measures and age. Gray matter thickness differences were noted in numerous regions previously reported to undergo prominent atrophy with age. Recommendations are provided for mitigating this potential confound, and highlight how the procedure may lead to more accurate measurement and comparison of anatomical features. Hum Brain Mapp 38:472-492, 2017. © 2016 Wiley Periodicals, Inc.
authors.affiliation: Center for Vital Longevity and School of Behavioral and Brain Sciences, University of Texas at Dallas, Dallas, Texas.
authors.forename: Neil K
authors.initials: NK
authors.lastname: Savalia
authors.affiliation: Center for Vital Longevity and School of Behavioral and Brain Sciences, University of Texas at Dallas, Dallas, Texas.
authors.forename: Phillip F
authors.initials: PF
authors.lastname: Agres
authors.affiliation: Center for Vital Longevity and School of Behavioral and Brain Sciences, University of Texas at Dallas, Dallas, Texas.
authors.forename: Micaela Y
authors.initials: MY
authors.lastname: Chan
authors.affiliation: Department of Behavioral Neuroscience, Oregon Health & Science University, Portland, Oregon.|Department of Medical Informatics and Clinical Epidemiology, Oregon Health & Science University, Portland, Oregon.
authors.forename: Eric J
authors.initials: EJ
authors.lastname: Feczko
authors.affiliation: Center for Vital Longevity and School of Behavioral and Brain Sciences, University of Texas at Dallas, Dallas, Texas.
authors.forename: Kristen M
authors.initials: KM
authors.lastname: Kennedy
authors.affiliation: Center for Vital Longevity and School of Behavioral and Brain Sciences, University of Texas at Dallas, Dallas, Texas.|Department of Psychiatry, University of Texas Southwestern Medical Center, Dallas, Texas.
authors.forename: Gagan S
authors.initials: GS
authors.lastname: Wig
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging; D016477:Artifacts; D001921:Brain / Q000000981:diagnostic imaging*; D001931:Brain Mapping; D005260:Female; D019416:Head Movements / Q000502:physiology*; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009038:Motion; D010100:Oxygen / Q000097:blood; D055815:Young Adult
chemical_list: D010100:Oxygen
keywords: MRI; aging; artifact; cortical thickness; head motion; quality control