This prospective study combining non conventional MRI techniques, neuropsychological screening tools, and a neurophysiological work-up using a sensitive and validated battery, will evaluate the predictive value of these measures and will explore the changes of the cognitive scores from baseline.

Neurologists are in need for reliable and robust predictive factors enabling to predict disease evolution and treatment response. Moreover, recent studies suggested that the evolution patterns of cognitive status in MS could be mixed, contradicting the concept that cognitive impairment in MS will inevitably increase over time.

The main aim of this prospective study is to investigate the predictors of disease evolution, as measured by the EDSS score, using a multiparametric assessment combining neuropsychological tests (BCcogSEP battery), MRI-derived metrics (volumetric brain parameters, tractography, diffusion tensor imaging and fiber tracking), patient-reported outcome measures, and neurophysiological tools (multimodal evoked potentials), and to explore the evolutionary patterns of cognitive status (changes from baseline).

The investigators planned to include 50 patients with active RRMS and initiating a new disease-modifying treatment.

Yearly assessment starting from study inclusion will be performed.

Inclusion Criteria:

• active MS, according to the Lublin criteria
• disease duration < 10 years before initiating or changing a disease-modifying therapies,
• relapse- and steroid-free for at least 1 month before MRI acquisition
• between 18-50 years old
• having given informed consent
• with no significant comorbidity other than MS or substance abuse that could interfere with cognitive performances

Exclusion Criteria:

• progressive forms of MS