title: Contour-based registration technique to differentiate between task-activated and head motion-induced signal variations in fMRI.
abstract: Data acquired using functional magnetic resonance imaging are often contaminated by head motion. As a result, optimal information regarding task-induced (or resting-state) signal changes cannot be extracted. Intensity-based registration methods, including intensity correlation or minimum intensity variance techniques, are widely used to register two or more images. It is shown here that intensity-based registration cannot accurately register two or more images in the presence of local intensity changes arising from functional magnetic resonance, fMRI, signals. In this paper, we present a contour-based technique that can be used not only for a more robust registration, but also to help differentiate between task-induced and motion-induced signal changes. Results obtained using both phantom and human brain images demonstrate advantages of this technique compared with a conventional intensity registration technique.
authors.affiliation: Biophysics Research Institute, Medical College of Wisconsin, Milwaukee 53226-0509, USA.
authors.forename: B B
authors.initials: BB
authors.lastname: Biswal
authors.forename: J S
authors.initials: JS
authors.lastname: Hyde
mesh_terms: D000328:Adult; D016477:Artifacts; D005260:Female; D019416:Head Movements; D006801:Humans; D007089:Image Enhancement / Q000379:methods*; D007091:Image Processing, Computer-Assisted / Q000379:methods*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008962:Models, Theoretical