Acute aerobic exercise changes brain activity during cognitive tasks

At AIST’s neuroimaging facility, healthy young and older adults performed cognitive tasks before and after acute aerobic exercise while functional MRI (fMRI)—brain scans used to measure activity—tracked regional changes. Working with the University of Texas Southwestern Medical Center, the AIST team reports that exercise altered regional brain activity patterns during those tasks. The study was published in the Journal of Magnetic Resonance Imaging.

The advance is methodological as much as biological. Repeating a task can change the brain’s response on its own, as participants become more familiar with it. The researchers designed repeated measurements to separate that repetition effect from the effect of aerobic exercise—an ambiguity that earlier studies had not sufficiently resolved.

The study found changes in regional brain activity after aerobic exercise and suggested that aerobic exercise may alter neural processes during cognitive tasks.

For older adults, the researchers observed a positive correlation between the decline in brain activity caused by task repetition and task performance. In plain English, a larger decline in activity with repetition was associated with better task performance. The researchers suggest that changes in brain activity associated with task habituation may be linked to more efficient task processing; the correlation does not establish causation.

So what changes for people outside the scanner? The immediate value is a way to make an otherwise subtle exercise effect visible, which could encourage people to continue exercising. For researchers, the method offers a cleaner way to test interventions aimed at maintaining cognitive function in older adults. The study concerns acute changes measured during cognitive tasks, not a demonstrated long-term prevention of cognitive decline or dementia.