Correlation Between Static Balance And Brain Activation During Standing In Older Adults With Mild Cognitive Impairment.

PURPOSE: The aim of this study was to investigate the correlation between static balance and prefrontal cortex activation levels during standing in old adults with mild cognitive impairment (MCI). METHODS: Twenty old adults with MCI (MCI group) and twenty old adults with normal cognition (Control group) were asked to stand bipedally for 30 seconds (age 71.0 ± 3.8 years vs 68.4 ± 4.8 years, height 159.71 ± 7.29 cm vs 163.53 ± 6.63 cm, years of education 5.2 ± 2.2 years vs 6.0 ± 2.9 years). A force platform was applied to measure the displacement trajectory of the center of pressure (COP) to assess balance and a functional near-infrared spectroscopy (fNIRS) was applied to measure the activation level of the prefrontal lobe. The prefrontal cortex was divided into the extreme prefrontal cortex (FPC), dorsolateral prefrontal cortex (DLPFC), lateral prefrontal cortex (VLPFC), and orbital prefrontal cortex (OFC) according to the Montreal Neurological Institute (MNI) channel location information and Brodmann area (BA) criteria. Correlation analysis of balance and brain activation data was conducted using SPSS 26.0 software. RESULTS: In the control group, the swing path of COP was significantly and positively correlated with extreme prefrontal cortex (FPC) (r = 0.639, P = 0.003), but not in the MCI group. In the MCI group, both the maximal displacement of COP in the mediolateral direction (r = -0.468, P = 0.032) and the root mean square distance of COP (r = -0.485, P = 0.026) were significantly negatively correlated with the lateral prefrontal cortex (VLPFC), but not in the control group. CONCLUSION: The older adults with mild cognitive impairment might require more lateral prefrontal cortex activation (VLPFC) to compensate for maintaining static balance.