title: A computational multiresolution BOLD fMRI model.
abstract: Blood oxygenation level-dependent (BOLD) functional magnetic resonance imaging (fMRI) is a widely used method for brain mapping. BOLD fMRI signal detection is based on an intravoxel dephasing mechanism. This model involves bulk nuclear spin precession in a BOLD-induced inhomogeneous magnetic field within a millimeter-resolution voxel, that is, BOLD signal formation spans a huge spatial scale range from Angstrom to millimeter. In this letter, we present a computational model for multiresolution BOLD fMRI simulation, which consists of partitioning the nuclear spin pool into spin packets at a mesoscopic scale (∼10(-6) m), and calculating multiresolution voxel signals by grouping spin packets at a macroscopic scale range (10(-5) to 10(-3) m). Under a small-angle approximation, we find that the BOLD signal intensity is related to its phase counterpart (or BOLD fieldmap) across two spatial resolution levels.
authors.affiliation: Mind Research Network, Albuquerque, NM 87106, USA. zchen@mrn.org
authors.forename: Zikuan
authors.initials: Z
authors.lastname: Chen
authors.forename: Vince
authors.initials: V
authors.lastname: Calhoun
mesh_terms: D001931:Brain Mapping / Q000379:methods*; D003198:Computer Simulation; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008954:Models, Biological; D010100:Oxygen / Q000097:blood / Q000737:chemistry; D012815:Signal Processing, Computer-Assisted
chemical_list: D010100:Oxygen