Neuroscience applications of ultra-high-field magnetic resonance imaging: mesoscale functional imaging of the human brain

Abstract

Abstract Functional MRI (fMRI) represents a key application of neuroimaging at ultra-high field strengths, because the dramatic increase in fMRI sensitivity with field strength enables new classes of experiments not possible at conventional field strengths. Recent insights indicate that, although fMRI tracks neural activity indirectly through measuring the associated hemodynamic responses, these hemodynamics are far more precisely coordinated than previously believed—perhaps at the fine spatial scale of the basic modules of functional architecture: cerebral cortical columns and layers. Thus the sensitivity boost provided at ultra-high fields can be utilized to increase the imaging resolution to enable investigations of mesoscale brain organization. This chapter surveys the current capabilities of fMRI at ultra-high fields, reviews what is currently known about the relationship between the fMRI signals and neural activity, showcases several illustrative applications of fMRI at ultra-high fields, and considers the role that ultra-high field fMRI can play in human neuroscience.