Decreased Hemodynamic Responses in Left Parietal Lobule and Left Inferior Parietal Lobule in Older Adults with Mild Cognitive Impairment: A Near-Infrared Spectroscopy Study
Affiliations: [a] Key Laboratory of Biomechanics and Mechanobiology, Ministry of Education, Beijing Advanced Innovation Center for Biomedical Engineering, School of Biological Science and Medical Engineering, Beihang University, Beijing, China
| [b] State Key Laboratory of Virtual Reality Technology and System, Beihang University, Beijing, China
| [c] School of Mechanical Engineering and Automation, Beihang University, Beijing, China
| [d] Department of Neurological Rehabilitation, Jiangbin Hospital of Guangxi Zhuang Autonomous Region, Nanning, China
Correspondence:
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Correspondence to: Wenyu Jiang, Department of Neurological Rehabilitation, Jiangbin Hospital of Guangxi Zhuang Autonomous Region, 85 Hedi Road, Nanning, 530000, China. Tel.: +86 771 2080621; E-mail: wenyu_jiang@163.com and Meiyun Xia, State Key Laboratory of Virtual Reality Technology and System, School of Mechanical Engineering and Automation, Beihang University, 37 Xueyuan Road, 100083, Beijing, China. Tel.: +86 18810702072; E-mail: xmy1234@buaa.edu.cn.
Abstract: Background:The brain activation patterns of mild cognitive impairment (MCI) are still unclear and they involve multiple brain regions. Most previous studies have focused on abnormal activation in the frontal and temporal lobes, with few investigating the entire brain. Objective:To identify and compare the changes in cerebral hemodynamics and abnormal activation patterns in the entire brain of MCI patients and healthy older adults. Methods:Patients with MCI (n = 22) and healthy controls (HC, n = 34) matched by age, education levels, sex, and mental state were enrolled. They performed the same letter and category verbal fluency test (VFT) tasks while their behavioral performance and global cerebral hemodynamics were analyzed. Results:The performance during the category VFT task was significantly better than that during the letter VFT task across all participants (HC: correct: p < 0.001; intrusions: p < 0.001; MCI: correct: p < 0.001; intrusions: p < 0.001). The number of correct words during the letter and category VFT tasks was significantly higher in the HC group than in the MCI group (p < 0.001). The deoxygenated-hemoglobin (HbR) concentrations in the left parietal lobule (p = 0.022) and left inferior parietal lobule (p = 0.034) were significantly different during the category VFT task. Conclusion:The differences between HC and MCI groups were greater in the category task. The HbR concentration was more sensitive for the category VFT task and concentration changes in the left parietal lobule and left inferior parietal lobule may be useful for clinical screening and application; thus, they deserve more attention.
