Methodologies and mechanisms are provided for introducing one or more magnetizable particles introduced non-invasively into one or more body structures containing nervous tissue in a subject, directing, guiding, transporting, focusing and/or concentrating the one or more particles using at least one image-guidance component in proximity to the one or more body structures which can direct the one or more particles within the one or more body structures, and modulating, using at least one activation component, the one or more particles to modulate neuronal function in the one or more body structures of the subject.