OUTLINE: Patients undergo MRI perfusion imaging and functional (fMRI) (standard structural imaging sequences, diffusion tensor imaging, arterial spin labeled perfusion imaging at rest, blood oxygen level dependent, and dynamic susceptibility contrast perfusion weighted MRI) at baseline and 3 and 6 months after completion of radiotherapy. Patients may perform tasks for fMRI studies, including finger tapping, photic stimulation with a flashing light, solving math problems, comparing shapes, giving a speech, or listening to and reciting lists of words during fMRI image acquisition. Patients also undergo daily fractionated intensity-modulated radiotherapy.