The researchers from Italy looked at functional MRI (fMRI) patterns of the brain in clinically isolated syndrome (CIS) patients during the performance of attention tasks using the Variable Attentional Control (VAC) task. It has previously been shown in patients with definite MS to have abnormalities of brain activity while doing attention tasks.
They found that the CIS patients have reduced accuracy and greater reaction time at the test compared to controls. Blood oxygenation level-dependent (BOLD)-fMRI showed greater activity in the right parietal cortex in CIS patients. Within the left putamen, greater activity was seen at the lower level and decreased activity at the greater level of attentional control demand.
This suggests a relationship between putaminal functional impairment and failure of sustained attention and processing speed in CIS patients. Therefore we see the failure of attentional control processing in the earliest stages of MS.
Authors: Tortorella C, Romano R, Direnzo V
Source: Mult Scler. 2013 Jan 17. [Epub ahead of print]
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