Attention deficits in Japanese multiple sclerosis patients with minor brain lesion loads

Abstract

Background

To investigate whether Japanese multiple sclerosis (MS) patients with minor brain lesion loads have attention deficits and brain atrophy, and to correlate their circumstance.

Method

Twenty-one Japanese patients with relapsing-remitting MS were included in this study. Attention deficits were evaluated using Clinical Assessment for Attention (CAT) standardized according to age groups. Lesion load in the brain was assessed by tallying the total volume of plaques visible on brain magnetic resonance imaging (MRI). The width of the third ventricle and the bicaudate ratio were measured.

Results

The completion time for the visual cancellation tasks and/or the reaction times for the continuous performance test were prolonged in 14 patients (66.7%). The accuracy of responses was preserved throughout the CAT. Deviation from the normal value was not exaggerated based on the increasing difficulty of the task. The total volume of plaques on brain MRI was small. The width of the third ventricle was significantly increased in patients with MS when compared to controls, but was not correlated with the low performance on the CAT.

Conclusions

Japanese MS patients with minor brain lesion loads frequently had attention deficits characterized by slowness of automatic information processing, but controlled processing that requires working memory demands was spared.

Keywords:

• attention
• cognitive function
• magnetic resonance imaging
• multiple sclerosis

Acknowledgments

This study was supported by a grant from the Tamagawa University Center of Excellence from the Ministry of Education, Culture, Sports, Science and Technology (MEXT) and the Core Research for Evolutionary Science and Technology (CREST; no 17022035) and by a Grant-in-Aid for Scientific Research on Priority Areas-System Study on Higher-order Brain Functions from MEXT (no 20020026). This study was also supported in part by a Showa University Grant-in-Aid for Innovative Collaborative Research Projects and a Special Research Grant-in-Aid for Development of Characteristic Education from MEXT.

Disclosure

The authors report no conflicts of interest in this work.