‘Aging’ Reduces Dual-Task Performance by Changing Prefrontal Cortex Activity Patterns

In daily living, we often perform different tasks simultaneously rather than one single task at a time. For example, we walk while talking or we walk while drinking coffee. This ability to perform two tasks simultaneously is referred to as ‘dual-task ability.’ The assessment of dual-task walking abilities helps to determine physical or cognitive changes in the elderly, and this is useful for confirming changes that may be occurring due to their aging. For example, during dual-task walking, the elderly may exhibit a slower gait speed, shorter stride length, and higher gait variability than younger subjects. In addition, since dual task ability is highly associated with the prefrontal cortex, dual-task walking can help to confirm changes to the prefrontal cortex, which is vulnerable to aging. The prefrontal cortex is responsible for the cognitive process and executive function.

Recent studies on dual-tasks and aging are increasingly focusing on the measurement of the functional activation of the prefrontal cortex during dual-task walking using functional near-infrared spectroscopy.

The research group of Professor Kim Hyeong-Dong and Baek Chang-Yoon (doctoral course student) in the Department of Health Science of the College of Health Science (Major in Rehabilitation Sciences) analyzed and compared the activity pattern of the prefrontal subregions (dorsolateral prefrontal cortex, rostral prefrontal cortex, ventrolateral prefrontal cortex, orbitofrontal cortex) and the walking test and cognitive task performance abilities of elderly and young subjects according during early and late periods ofdual-task walking.

The results of the research were published in the Journal of NeuroEngineering and Rehabilitation (Impact Factor: 5.1, JCR: 98%, top 2%), a prestigious international journal.
*Title of article: Change in Activity Patterns in the Prefrontal Cortex in Different Phases during the Dual-Task Walking in Older Adults

In this study, the prefrontal subregions were mapped using a 48-channel functional near-infrared spectroscope. The activity of each region was measured over time during single-task walking and dual-task walking.

Professor Kim’s group discovered various activity patterns that were changed by aging in several prefrontal subregions. Furthermore, the altered activity patterns exhibited a significant correlation with the decreases in the dual-task walking and cognitive task abilities of the elderly. The results could make great contributions to the understanding of the neural mechanism of age-related decrease in dual-task performance abilities and significantly help further studies on the topic. Professor Kim explained the significance of the research, “We confirmed the changed activity patterns of the subjects whose executive function is decreased by aging. This may partially help to identify the group at high-risk of falling.”