In SPM8, the same procedure for statistical thresholding as described in Section 2.4.1. was used. Results Behavioral data Results from the prescanning behavioral tasks suggested a distinction between complex

and noncomplex tasks. In noncomplex cognitive tasks, there were no significant performance differences between MS participants and controls. This is shown by the statistical Inhibitors,research,lifescience,medical results on the digit span (P = 0.09) and the story recall (P = 0.27) tasks, see Table ​Table2.2. However, it should be noted that the differences between MS participants and controls were marginally significant for the digit span task. In complex tasks, on the other hand, the differences between the groups were highly significant. That is to say both the complex figure test (P

= 0.009) and the working memory Inhibitors,research,lifescience,medical span task (P = 0.0002) resulted in significant differences between the groups. There was also a significant difference between MS participants and controls in the vocabulary task (P = 0.03). Inhibitors,research,lifescience,medical During the fMRI session, MS participants performed worse than controls at all levels of difficulty of the working memory task (Fig. ​(Fig.2A)2A) and they also had longer reaction times (Fig. ​(Fig.2B).2B). As revealed by the self-Selleck BMS 387032 reported questionnaire (PDQ), the MS participants reported more problems with cognitive function compared to controls, P < 0.05 (Table ​(Table22). Figure 2 Performance during the four different difficulty levels (levels 1–4) of the working memory task administered during fMRI scanning. (A) Performance of word recognition measured as hits – false alarms. (B) Reaction Inhibitors,research,lifescience,medical time during word recognition. ... After the Inhibitors,research,lifescience,medical fMRI examination, MS participants rated higher on

the fatigue (P < 0.001) and sleepiness (P < 0.05) VAS compared to controls. However, there were no significant differences between the two groups in ratings of depression (P > 0.1) and anxiety (P > 0.1; see Table ​Table2).2). There were no significant differences between the scorings before and after the fMRI examination in either the MS group or in the control group. MS participants rated higher on fatigue VAS and they also performed worse on the working until memory tasks administered before and during fMRI. There was a significant correlation between perceived fatigue and working memory performance during fMRI (P = 0.02). However, there was no correlation between fatigue scores and performance on the working memory span task administered before fMRI (P = 0.29). Brain activation in controls As shown in Figure ​Figure3,3, at the whole brain level of analysis, several cortical and subcortical areas were activated during the working memory task in controls.