The study will evaluate connectivity regardless whether patients present a clinical type that requires medical treatment. In this point, investigators will include patients with progressive evolution as well as initial forms of the disease (CIS) and properly established forms of multiple sclerosis (MS) in remittent-recidivant (RR) forms. The researches will not focus on medical treatment as some of these clinical forms have no indication for disease modifying drugs.

To date, no clear consensus has been reached related to default mode network (DMN) activity and different clinical types of MS. Due to this controversy on the literature regarding increment and decrement of DMN activity along the natural history of MS evolution, this study aim to add experimental information and more data that might help to disentangle this paradox, also correlating this DMN activity with anatomic and cognitive indexes. The investigators will also introduce a novel experimental design, including a prospective measure of the investigators connectivity and cognitive measures.

In this study, investigators aim to evaluate connectivity regardless whether patients present a clinical type that requires medical treatment. In this point, patients with progressive evolution as well as initial forms of the disease (CIS) will be included and properly established forms of MS in RR forms. Researchers will not focus on medical treatment as some of these clinical forms have no indication for disease modifying drugs. Nevertheless, investigators consider that the study of connectivity is worth regardless their pharmacological treatment.

The investigators also aim to offer data on the natural history of MS evolution for distinct MS type patients and healthy controls, as this study is planned to collect data longitudinally.

Inclusion Criteria:

• MS diagnostic following McDonald 2010 diagnosis criteria.
• 18 to 60 years old.
• Consent form signature.

Exclusion Criteria:

• Dementia diagnosis, following Spanish Neurological Society criteria.
• Mayor psychiatric illness.
• Physical or intellectual limitations to successfully perform - neuropsychological evaluation.
• Any other circumstance that may interfere with functional magnetic resonance session.
• Abnormal renal function previous to magnetic resonance image (MRI) session.