The main research interest of the Neuroimaging of CNS White Matter Unit is multiple sclerosis (MS) and white matter disorders. The major goals of the Unit in this field are the following: - To define the mechanisms responsible for the accumulation of cognitive impairment and irreversible disability in patients with MS and its variants. - To study brain cortical reorganization secondary to MS-related structural tissue damage. - To identify structural and functional MR markers for white matter diseases, including migraine, cluster headache, CADASIL, LHON, NPSLE, and primary CNS vasculitidis.