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Updated: Jun 11, 2026
Functional Neuroimaging Using Ultrasonic Blood-brain Barrier Disruption and Manganese-enhanced MRI
Published on: July 12, 2012
Altered working memory process in the manganese-exposed brain
Yongmin Chang1, Jae-Jun Lee, Jee-Hye Seo
1Department of Molecular Medicine, Kyungpook National University College of Medicine, Kyungpook National University Hospital, 50, Samduk-Dong 2Ga, Chung-Gu, Daegu 700-721, South Korea.
Abstract:
Chronic manganese (Mn) exposure often leads to impairments in fine motor and cognitive functions, particularly memory. However, the neural correlates of Mn-induced alterations in memory remain unclear. In the present study, we performed functional MRI (fMRI) with 2-back memory tests to assess the neural correlates of Mn-induced memory impairment in response to subclinical dysfunction in the working memory networks in welders exposed to Mn for extended periods of time. Within-group and between-group analyses revealed that brain activity in working memory networks was increased in welders with chronic Mn exposure during the 2-back verbal working memory task compared to healthy control individuals. Therefore, our fMRI findings indicate that welders might require more neural resources in working memory networks to compensate for subtle deficits in working memory and altered working memory processes, even if they performed the tasks at the same level as healthy control individuals.
Insights
Chronic manganese (Mn) exposure increases brain activity in working memory networks for welders. This suggests welders may need more neural resources to compensate for subtle memory deficits caused by manganese exposure.
Area of Science:
- Neuroscience
- Occupational Health
- Toxicology
Background:
- Chronic manganese (Mn) exposure is linked to cognitive impairments, especially memory deficits.
- The specific brain mechanisms underlying Mn-induced memory alterations are not fully understood.
- Welders represent an occupational group with potential for significant Mn exposure.
Purpose of the Study:
- To investigate the neural correlates of Mn-induced memory impairment using functional MRI (fMRI).
- To assess subclinical dysfunction in working memory networks in welders with chronic Mn exposure.
- To compare brain activity during a memory task between exposed welders and healthy controls.
Main Methods:
- Functional MRI (fMRI) was employed to measure brain activity.
- A 2-back memory test was administered to assess working memory function.
- Analysis included within-group and between-group comparisons of brain activity.
Main Results:
- Welders with chronic Mn exposure showed increased brain activity in working memory networks during a verbal working memory task.
- This heightened activity was observed compared to healthy control individuals.
- The findings suggest compensatory mechanisms are engaged.
Conclusions:
- Increased neural resource recruitment in working memory networks may indicate compensation for Mn-induced subtle memory deficits.
- Functional MRI reveals potential neural adaptations to chronic manganese exposure in occupational settings.
- These findings highlight the importance of monitoring cognitive function in Mn-exposed workers.
