Characteristics In Prefrontal Cortex Activity And Gait Performance During Curve-path Walking In Older Adults

With aging, people will have a decrease in gait and neural control ability. Older adults are more likely to fall, the demand for motor control are higher during curved path than straight path walking. Motor control requires the involvement of prefrontal cortex (PFC). Most studies have reported differences in PFC activation or gait performance during straight walking in older adults. No studies have reported on the characteristics of PFC activation and gait performance during curved and straight path walking in older and young adults. PURPOSE: To investigate the differences between the PFC activation and gait performance during curved path walking, during older and young adults. METHODS: Twenty older adults (69 ± 3 years) and 15 younger adults (24 ± 1 years) were included. Participants were required to perform two tasks: walking on the curved path in figure-of-eight shape and 10-meter straight path, each test was performed for 30s and three times. Functional near-infrared spectroscopy (fNIRS) and three-dimensional motion capture system was used to collect data. Measured included PFC activation and stride length. Two-factor repeated measures analysis of covariance (ANCOVA) was used to compare age with task factors, with gait speed as the covariance. RESULTS: A significant interaction was found between left dorsolateral PFC (DLPFC; P = 0.038) and stride length (P = 0.04). Post-hoc test showed that compared with young adults, the left DLPFC activation was increased (young:0.27 ± 3.60; older:3.55 ± 3.66; P = 0.017,ηp2 = 0.16), and stride length was decreased (young:1.07 ± 0.08; older:1.01 ± 0.09; P < 0.01, ηp2 = 0.73) in older adults during curved walking. Compared with straight walking, the left DLPFC activation was increased (straight-path:-0.65 ± 3.82; curve-path:3.55 ± 3.66; P < 0.01, η = 0.44) during curved walking in older adults. CONCLUSIONS: Our results showed that DLPFC activation was increased and stride length was decreased, during the complex curved walking with aging. We speculated that the neural resources of DLPFC may be used to overcome the challenges of aging and complex curved-path walking. Stride length may be reduced to adjust the more cautious gait pattern, which adapted to environmental changes and maintain gait performance. National natural science Foundation of China(12102235)