Reduced functional adaptation to working memory tasks with increasing complexity in patients with early stages of relapsing-remitting multiple sclerosis

Abstract

We investigated functional activation and connectivity in patients with early forms of relapsing-remitting multiple sclerosis (MS) on a 3T-scanner. So far, 6 MS patients and 6 controls performed an alertness task and three N-back tasks with increasing task difficulty. Significant differences between patients and controls were found in 2-back and 3-back, where patients had higher activation in medial frontal gyrus. In controls, the contrast between 3-back and 1-back showed a widely distributed change of activation, whereas in patients only sparse increase of signal was detected. The functional connectivity analysis revealed a slight trend of decreased connectivity in patients.