title: Quest for an open MRI scanner.
abstract: A study of the motor cortex during the programming, execution and mental representation of voluntary movement is of great relevance; its evaluation in conditions close to reality is necessary, given the close integration of the visuomotor, sensory feedback and proprioceptive systems, as of yet, a functional Magnetic Resonance Imaging (fMRI) scanner allowing a human subject to maintain erect stance, observe the surroundings and conserve limb freedom is still a dream. The need for high field suggests a solenoid magnet geometry that forces an unnatural posture that affects the results, particularly when the motor cortex is investigated. In contrast in a motor functional study, the scanner should allow the subject to sit or stand, with unobstructed sight and unimpeded movement. Two approaches are presented here to solve this problem. In the first approach, an increased field intensity in an open magnet is obtained lining the "back wall" of the cavity with a sheet of current: this boosts the field intensity at the cost of the introduction of a gradient, which has to be canceled by the introduction of an opposite gradient; The second approach is an adaptation of the "double doughnut" architecture, in which the cavity widens at the center to provide additional room for the subject. The detailed design of this kind of structure has proven the feasibility of the solution.
authors.affiliation: Robotics, Brain and Cognitive Sciences Department, Istituto Italiano di Tecnologia, Genova, Italy.
authors.forename: Franco
authors.initials: F
authors.lastname: Bertora
authors.affiliation: Robotics, Brain and Cognitive Sciences Department, Istituto Italiano di Tecnologia, Genova, Italy.
authors.forename: Alice
authors.initials: A
authors.lastname: Borceto
authors.affiliation: Robotics, Brain and Cognitive Sciences Department, Istituto Italiano di Tecnologia, Genova, Italy.
authors.forename: Andrea
authors.initials: A
authors.lastname: Viale
authors.affiliation: Robotics, Brain and Cognitive Sciences Department, Istituto Italiano di Tecnologia, Genova, Italy.
authors.forename: Giulio
authors.initials: G
authors.lastname: Sandini
mesh_terms: D001931:Brain Mapping / Q000295:instrumentation*; D017076:Computer-Aided Design; D004867:Equipment Design; D019544:Equipment Failure Analysis; D006804:Ergonomics / Q000295:instrumentation*; D007089:Image Enhancement / Q000295:instrumentation*; D008279:Magnetic Resonance Imaging / Q000295:instrumentation*; D059346:Magnets; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D014159:Transducers
keywords: Functional magnetic resonance; MRI scanner; cerebral activation; driving simulator; magnet design; motor cortex