: Multiple Sclerosis (MS) is the most frequent disabling neurological disease in young adults. Over the past two decades, cognitive impairment in MS has received increasing interest. Although for a long time described in MS text books, it has been underestimated until recently. It is now accepted as an important feature of MS with a high impact on working and social abilities. The cognitive disorders in MS are dominated by a slowdown in information processing speed (IPS), as well as disturbances of attention and memory. The nature of cognitive findings suggest that the impairments depend on the integrity of large-scale cortical integrative processes, which involve long-distance white matter projections which can be impaired due to diffuse demyelinating injury in patients with MS. At the early stages of MS there is increasing evidence that neuroplasticity, the ability of the brain to respond to various insults, allows adaptive reorganization of cognitive functions to limit impairment, despite widespread tissue damage. Recently, we showed that at the early stages of RRMS compensatory capacities are relatively maintained, especially in highly-educated patients suggesting that cognitive training might be useful. The requirement of cerebral compensatory mechanisms to perform the cognitive tests was postulated in MS patients on the basis of functional MRI (fMRI) studies. By using a go/no go task of increasing complexity in a fMRI study in RRMS patients, we observed that a limitation of this compensatory cerebral recruitment appears when the attentional solicitations reach a particular level of difficulty. We postulate that a cognitive training program may help to maintain these compensatory capacities. Therefore, we propose to evaluate the effect of the program on brain activation using a task with several levels of attention requirement (increased attention load) by using fMRI and to evaluate in parallel its clinical effect and its impact in daily activities.