Study: Physical fitness helps bolster older adult brains

Editor's Note

Research by the Center for Longevity at the University of Texas, Dallas, suggests that older adults who engage in intensive fitness practices tend to have brains that more closely resemble those of younger adults, the August 23 UTDallas News reports.

The study, which compared high-fit older adults (median age 73) with younger adults (median age 26), used functional MRI to measure fluctuations in blood oxygen level-dependent signals as participants performed tasks involving cognitive control.

The MRI scans showed that:

• Young adults primarily used the dorsolateral prefrontal cortex (a working memory, cognitive control center of the brain that is activated more as tasks become more demanding)--younger brains are more efficient and only use this region when things become more difficult.
• High-fit older adults overactivated the dorsolateral prefrontal cortex only at moderate levels of task difficulty but compensated by activating the superior parietal lobe of the brain.
• Low-fit older adults used the dorsolateral prefrontal cortex even for the simplest tasks.
• The differences in task performance and brain activity between young and high-fit older participants were much smaller than gaps between high-fit and low-fit older adults.

The findings show that high levels of physical activity and high cardiorespiratory fitness allow older adults to recruit additional brain regions that help compensate and maintain levels of accuracy, the authors say.