The alertness subtest of the Test of Attentional Performance may offer an objective method of evaluating self-reported fatigue, and may therefore - in addition to the Fatigue Severity Scale - be a suitable tool for the assessment of multiple sclerosis patients complaining of fatigue.

Declarative memory has been reported to rely on the medial temporal lobe system, whereas non-declarative memory depends on basal ganglia structures. We investigated the functional role of the subthalamic nucleus (STN), a structure closely connected with the basal ganglia for both types of memory. Via deep brain high frequency stimulation (DBS) we manipulated neural activity of the STN in humans. We found that DBS-STN differentially modulated memory performance: declarative memory was impaired, whereas non-declarative memory was improved in the presence of STN-DBS indicating a specific role of the STN in the activation of memory systems.

The Brief Repeatable Battery of Neuropsychological Tests (BRB-N) is a neuropsychological screening battery, often applied in multiple sclerosis (MS) patients. It is almost exclusively administered in trials and not in the daily practice routine because of the lack of normative values. Using a stepwise linear regression analysis, the dependence of test results on age, gender, and education of 241 healthy control subjects was investigated. Z-values of -1.68 or less were considered pathological. Based on the normative values, the proportions of cognitively impaired patients with relapsing-remitting MS (RRMS, n=43) and secondary progressive MS patients (SPMS, n=60) were calculated. The regression model explained 2.7-25.0% of the variance of test performances. Cognitive impairment occurred in 38% and in 47% of the RRMS and the SPMS groups, respectively. In both groups attention and concentration impairment was prominent, while in the SPMS group memory was also frequently affected. The proportion of cognitively impaired MS patients reflected the figures that could be found in the literature.

Reliable, language-independent, short screening instruments to test for cognitive function in patients with multiple sclerosis (MS) remain rare, despite the high number of patients affected by cognitive decline. We developed a new, short screening instrument, the Faces Symbol Test (FST), and compared its diagnostic test characteristics with a composite of the Digit Symbol Substitution Test (DSST) and the Paced Auditory Serial Addition Test (PASAT), in 108 MS patients and 33 healthy controls. An Informant-Report Questionnaire, a Self-Report Questionnaire, and a neurologist's estimation of the Every Day Life Cognitive Status were also applied to the MS patients. The statistical analyses comprised of a receiver operating characteristic analysis for test accuracy and for confounding variables. The PASAT and DSST composite score estimated that 36.5% of the MS patients had cognitive impairment. The FST estimated that 40.7% of the MS patients were cognitively impaired (sensitivity 84%; specificity 85%). The FST, DSST and PASAT results were significantly correlated with the patients' physical impairment, as measured by the Expanded Disability Status Scale (EDSS). The results suggest that the FST might be a culture-free, sensitive, and practical short screening instrument for the detection of cognitive decline in patients with MS, including those in the early stages.

Treating MS is a challenge and to positively influence the course of the disease it is necessary to administer medication in a constant manner. Our data showed a moderate compliance and satisfaction with the immunomodulating medication. Adverse effects and perceived lack of treatment effect were reasons for discontinuation of therapy. To increase compliance and satisfaction with treatment, adequate information about MS, the therapeutic options, handling of medication, side-effects and their management are necessary. Additionally, realistic therapeutic aims should be discussed with the patients.