New research visualizes how aerobic exercise alters brain activity patterns

Researchers at AIST, in collaboration with the University of Texas Southwestern Medical Center in the United States, examined changes in brain activity during cognitive tasks before and after acute aerobic exercise in young and older healthy adults. As a result, the researchers succeeded in distinguishing between the effects of exercise itself and the effects of task repetition resulting from repeating cognitive tasks between exercise intervals, a distinction that had not been sufficiently differentiated in previous studies. They demonstrated that aerobic exercise alters regional brain activity patterns during cognitive tasks and that task repetition strongly influences the efficiency of brain activity during such tasks. 

Exercise is believed to be effective in preventing cognitive decline and dementia. To enhance these benefits, it is important to evaluate changes in brain activity during cognitive tasks that occur before and after exercise. However, accurately capturing these changes in brain activity requires distinguishing whether they result from the "exercise" itself or from the "task repetition" caused by performing the cognitive task repeatedly, which is difficult to differentiate in practice. Consequently, it has not been fully clarified how exercise affects brain activity during cognitive tasks. 

In this study, the research group took advantage of the state-of-the-art neuroimaging facility at the AIST, which allows for repeated measurements of brain activity using functional MRI. Based on these measurements, they introduced a research design capable of distinguishing between the effects of aerobic exercise on brain activity during cognitive tasks and the effects of task repetition. The results suggested that aerobic exercise may alter neural processes during cognitive tasks. Furthermore, in older adults, a positive correlation was observed between the decline in brain activity due to task repetition and task performance. This suggests that changes in brain activity associated with task habituation may be linked to more efficient task processing. 

While the effects of exercise on cognitive function are difficult to perceive in daily life, visualizing changes in brain activity during cognitive tasks performed before and after exercising can make it easier to appreciate the benefits of the intervention, which may encourage people to continue exercising. Such efforts are also expected to contribute to the prevention of future cognitive decline. Furthermore, this study deepens our understanding of the role that not only exercise interventions but also the repeated performance of cognitive tasks themselves play in maintaining cognitive function. These findings could lead to the development of new intervention methods to support cognitive function in older adults. 

Background 

In an aging society, preventing cognitive decline and dementia has become a critical issue not only in the fields of healthcare and long-term care but also for maintaining quality of life (QOL). Previous studies have reported that engaging in aerobic exercise, such as walking or jogging, acutely improves performance on cognitive tasks after exercise compared to before, suggesting that exercise may have a positive effect on cognitive function. However, many previous studies have primarily evaluated the effects from a behavioral perspective, such as changes in performance on cognitive task. These studies have not sufficiently clarified what changes occur in brain activity itself while participants are performing these tasks. Clarifying how aerobic exercise alters brain activity during cognitive tasks is expected to advance our understanding of how exercise affects the brain and lead to the development of more effective intervention methods. 

Points

• Introduced and implemented a research design that distinguishes between the effects of "exercise" and "task repetition"-the repetition of cognitive tasks 
• It was revealed that "exercise" alters brain activity patterns during cognitive tasks, whereas "task repetition" strongly influences the efficiency of brain activity during cognitive tasks 
• By visualizing changes in brain activity during cognitive tasks before and after exercise, the effects of the intervention become clearer, raising expectations for its application in promoting continued exercise and preventing future cognitive decline