title: Multivariate fMRI Analysis using Optimally-Discriminative Voxel-Based Analysis.
abstract: This significantly extends Multi-Voxel Pattern Analysis (MVPA) methods, such as the Searchlight and related methods, by building on an approach that was recently proposed for structural brain images, and was named Optimally-Discriminative Voxel-Based Analysis (ODVBA), which uses machine learning models to determine the optimal anisotropic filtering of images that enhances group differences. Precise spatial maps of activation are computed by tallying the weights of each voxel to all of the neighborhood in which it belongs, and significance maps are obtained via permutation testing. We adapt this idea to both single and multi-subject fMRI analysis. Both simulated data and real data from 12 adolescent subjects who completed a standard working memory task demonstrated the use of ODVBA in fMRI improves accuracy and spatial specificity of activation detection over Searchlight.
authors.affiliation: Department of Radiology, University of Pennsylvania, Philadelphia, PA 19104, USA.
authors.forename: Tianhao
authors.initials: T
authors.lastname: Zhang
authors.affiliation: Department of Psychiatry, University of Pennsylvania, Philadelphia, PA 19104, USA.
authors.forename: Theodore D
authors.initials: TD
authors.lastname: Satterthwaite
authors.affiliation: Department of Radiology, University of Pennsylvania, Philadelphia, PA 19104, USA.
authors.forename: Mark
authors.initials: M
authors.lastname: Elliott
authors.affiliation: Department of Radiology, University of Pennsylvania, Philadelphia, PA 19104, USA ; Department of Psychiatry, University of Pennsylvania, Philadelphia, PA 19104, USA ; Philadelphia Veterans Administration Medical Center, Philadelphia, PA 19104, USA.
authors.forename: Ruben C
authors.initials: RC
authors.lastname: Gur
authors.affiliation: Department of Radiology, University of Pennsylvania, Philadelphia, PA 19104, USA ; Department of Psychiatry, University of Pennsylvania, Philadelphia, PA 19104, USA ; Philadelphia Veterans Administration Medical Center, Philadelphia, PA 19104, USA.
authors.forename: Raquel E
authors.initials: RE
authors.lastname: Gur
authors.affiliation: Department of Radiology, University of Pennsylvania, Philadelphia, PA 19104, USA.
authors.forename: Christos
authors.initials: C
authors.lastname: Davatzikos
keywords: MVPA; ODVBA; Searchlight; fMRI