Assessing brain and cognitive function in multiple sclerosis cross-sectionally and longitudinally with multimodal methods : insights form high-density electrophysiology, neuropsychological examination and magnetic resonance imaging

Abstract

Cognitive impairment (CI) affects up to 65% of multiple sclerosis (MS) patients and can occur in the absence of physical disability (Hoffmann, Tittgemeyer, & von Cramon, 2007). MS is the most common chronic inflammatory demyelinating disease affecting the central nervous system among young adults in Western countries leading to severe disability, as there is no cure (Filippi, 2011). During early disease course, 85% of MS patients present with alternating periods of incapacitating relapses and stable remissions (relapsing-remitting MS, RRMS). This later develops into the secondary-progressive (SPMS) phase, characterised by less relapses but increasing disability. A minority (15%) of patients have a progressive accumulation of disability without relapses (primary-progressive, PPMS)(Rejdak, Jackson, & Giovannoni, 2010). CI in MS occurs most often for information processing speed, attention and working memory (Rogers & Panegyres, 2007). CI in MS is to some degree related to concurrent brain changes such as lesions (R.H. Benedict & Zivadinov, 2011). CI may significantly limit the independence and quality of life of MS patients (Amato, et al., 1995). Thus it is crucial to create innovative methods to support the early detection, efficient monitoring and treatment of the CI in MS.