This study aimed to reveal the physiological mechanism in subjects with mild cognitive impairment based on effective connectivity method.
Effective connectivity was assessed by dynamic Bayesian inference of the oxygenated hemoglobin concentration signals measured through functional near-infrared spectroscopy. The oxygenated hemoglobin concentration signals were recorded from the left prefrontal cortex, right prefrontal cortex, left motor cortex, right motor cortex, left occipital lobe, and right occipital lobe of 26 subjects with mild cognitive impairment (mild cognitive impairment group) and 28 healthy elderly subjects (control group) at resting state.
The coupling strength of right prefrontal cortex to left prefrontal cortex (F = 7.964, P = 0.007) and left prefrontal cortex to right occipital lobe (F = 4.278, P = 0.044) in interval III as well as left prefrontal cortex to left occipital lobe (F = 5.637, P = 0.021), right occipital lobe to left prefrontal cortex (F = 4.762, P = 0.034), and right prefrontal cortex to left occipital lobe (F = 4.06, P = 0.049) in interval IV in the mild cognitive impairment group were significantly lower than those in the control group.
The decreased effective connectivity levels among brain regions may be a marker of impaired cognitive function in the mild cognitive impairment group. The constructed effective connectivity network based on functional near-infrared spectroscopy provide a noninvasive method to assess mild cognitive impairment.
From the Department of Physical Medicine and Rehabilitation, Qilu Hospital, Shandong University, Jinan, PR China (LB, YW); Key Laboratory of High Efficiency and Clean Mechanical Manufacture, School of Mechanical Engineering, Shandong University, Jinan, PR China (LB); Beijing Key Laboratory of Rehabilitation Technical Aids for Old-Age Disability, National Research Center for Rehabilitation Technical Aids, Beijing, PR China (CH, GX, ZL); School of Mechanical and Electronic Engineering, Shandong Jianzhu University, Jinan, PR China (YQ); and Key Laboratory of Rehabilitation Aids Technology and System of the Ministry of Civil Affairs, Beijing, PR China (ZL).
All correspondence should be addressed to: Yonghui Wang, PhD, Department of Physical Medicine and Rehabilitation, Qilu Hospital, Shandong University, 107 Wenhua West Rd, Lixia District, Jinan, Shandong Province, China 250012; and Zengyong Li, PhD, National Research Center for Rehabilitation Technical Aids, 1 Ronghuazhong Rd, Beijing Economic and Technological Development Zone, Beijing, China 100176.
YW and ZL contributed equally to this work.
The study was supported by the National Natural Science Foundation of China (NSFC Number 31771071, 61761166007, 11732015, and 81672249) and Fundamental Research Funds for Central Public Welfare Research Institutes (118009001000160001).
Financial disclosure statements have been obtained, and no conflicts of interest have been reported by the authors or by any individuals in control of the content of this article.