According to this study, "our results show that cognitive rehabilitation is a promising approach in treating MS-related cognitive impairment." If you you have cognitive issues, perhaps it is time to more seriously consider subscribing to one of the internet brain game sites (like Lumosity).
http://www.posters2view.com/ECTRIMS2011/view.php?nu=334
http://www.posters2view.com/ECTRIMS2011/view.php?nu=334