<qa>  What is the effect of teriflunomide on cognitive capacity in MS patients?Cognitive impairment is common in MS and has devastating impact on functional activities. There is a great demand for medications that will enhance cognitive capacity in MS patients. The effect of teriflunomide on cognition and vocational capacity is unknown. The investigators will address these questions in a sample of 30 relapsing MS patients treated with teriflunomide. Cognitive impairment will be measured by calculating an information processing speed index and a memory composite index from conventional, validated neuropsychological tests as recommended by consensus opinion publications. Vocational performance will be monitored using a newly developed online survey called the Multiple Sclerosis Vocational Monitoring Survey MSVMS. This study will elucidate the effect of teriflunomide on these important outcomes. 