title: Prospective slice-by-slice motion correction reduces false positive activations in fMRI with task-correlated motion.
abstract: OBJECTIVE
  We aimed to test the hypothesis that slice-by-slice prospective motion correction at 7T using an optical tracking system reduces the rate of false positive activations in an fMRI group study with a paradigm that involves task-correlated motion.
  
  
  METHODS
  Brain activation during right leg movement was measured using a block design on 15 volunteers, with and without prospective motion correction. Clearly erroneous activations were compared between both cases, at the individual level. Additionally, conventional group analysis was performed.
  
  
  RESULTS
  The number of falsely activated voxels with T-values higher than 5 was reduced by 48% using prospective motion correction alone, without additional retrospective realignment. In the group analysis, the statistical power was increased - the peak T-value was 26% greater, and the number of voxels in the cluster representing the right leg was increased by a factor of 9.3.
  
  
  CONCLUSIONS
  Slice-by-slice prospective motion correction in fMRI studies with task-correlated motion can substantially reduce false positive activations and increase statistical power.
authors: Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany. Electronic address: jschulz@cbs.mpg.de.
authors: J
authors: J
authors: Schulz
authors: T
authors: T
authors: Siegert
authors: P-L
authors: PL
authors: Bazin
authors: J
authors: J
authors: Maclaren
authors: M
authors: M
authors: Herbst
authors: M
authors: M
authors: Zaitsev
authors: R
authors: R
authors: Turner
mesh_terms: D000465:Algorithms; D016477:Artifacts; D001931:Brain Mapping / Q000379:methods*; D005260:Female; D006801:Humans; D007089:Image Enhancement / Q000379:methods*; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D007866:Leg / Q000502:physiology; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D009038:Motion; D009068:Movement / Q000502:physiology*; D011446:Prospective Studies; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013223:Statistics as Topic; D013647:Task Performance and Analysis; D055815:Young Adult
keywords: False positive activations; Magnetic resonance imaging; Optical motion tracking; Prospective motion correction; fMRI