OUTCOME MEASURES: The first outcome measure will be the MACFIMS and cortical thickness values. Correlation between these two metrics will be initially performed. Secondly, cortical lesions as well as white matter lesions on T1 and T2 weighted images, magnetization transfer ratios and diffusion tensor imaging metrics of lesional and normal appearing brain tissues will be computed and their impact in determining cognitive impairment will be determined. Thirdly, deep gray matter, white matter and total brain volume measures will be computed and correlated with cognitive function measured by the MACFIMS. Similarly, correlations between clinical disability, as measured by the EDSS score and cognitive impairment, as well as between EDSS score and each of the RMI variables explored in the study will be performed. Finally, the level of correlation between MACFIMS and ANAM tests will be investigated.