When an older adult sways while standing or carefully adjusts their footing on uneven ground, it’s probably not all about weakened muscles. New interdisciplinary research by a Carle Illinois College of Medicine faculty member and his team suggests these effects may be outward signs of changes in brain activity that accompany aging, even in healthy people. The study is a step toward identifying potential links between brain activity, balance, and fall risk, that could help target modifiable factors to reduce falls that threaten the health of older adults.
Photo by L. Brian Stauffer
CI MED Teaching and Research Associate Professor Manuel Hernandez is co-author of the study aimed at improving scientists’ understanding of the combination of sensory or physical challenges that can cause balance problems in aging adults. Hernandez and the research team used high-density electroencephalography (EEG) to record and evaluate brain activity in both younger adults (ages 18-30) and older adults (over 65) as they attempted to maintain balance when standing. “We found that increased brain activity is needed by healthy older adults to perform balance-demanding tasks at a similar level as young adults. Increased cortical effort is needed by older adults to maintain balance when eyes are open and are standing still on a solid surface. This is consistent with prior research findings in older adults while standing still and the theory of neural compensation,” said Hernandez, who is also a faculty member in the Department of Kinesiology and Community Health at the University of Illinois Urbana-Champaign.
Secondly, the researchers found that as they increased the difficulty of the balance task with challenging variables like changing in the angle of their feet or with eyes closed, older adults had more difficulty and exhibited a decrease in the cortical brain activity needed to maintain balance. “This is consistent with changes in strategies to maintain balance that need further examination,” Hernandez explained, noting that future research could help pinpoint a novel target to benefit older adults, including those with neurological conditions following neurorehabilitation. The work is especially important considering fall deaths among older adults in the US rose by 30% between 2007 and 2016.
The combined power of mobile neuroimaging and biomechanics used in this research offers a deeper insight into the interplay between changing brain activity and fall risk. “The ability to monitor brain activity while performing balance-demanding tasks opens the door to move beyond associations of cortical structure and function to balance capacity,” Hernandez said. “We get a clearer insight to the mechanisms that underlie balance, gait, and mobility in older adults with and without neurological disorders.” In terms of potential clinical application, Hernandez says the ability to identify where cortical brain activity declines and correlate it with difficult balance challenges in an individual patient could help identify areas to focus on during balance training.
Next steps in this research include examining balance performance in older adults with chronic spinal cord injury, in collaboration with Dr. Suguna Pappu, a CI MED Clinical Assistant Professor and neurosurgeon at Carle Health. Hernandez said he also plans a study to explore the benefits of evidence-based exercise, such as Tai Chi, on the control of balance in older adults.
Hernandez’s co-authors on this research study include Steven Petruzzello, a professor in the Department of Kinesiology and Community Health at UIUC, and former UIUC graduate student Yang Hu, who is now an assistant professor at San Jose State University.
Their study, “Beta cortical oscillatory activities and their relationship to postural control in a standing balance demanding test: influence of aging,” is available here in the journal Frontiers of Aging Neuroscience.
Editor’s note: Professor Hernandez is also affiliated with the Neuroscience Program in the College of Liberal Arts & Sciences, the Cognition, Lifespan Engagement, Aging and Resilience Group at the Beckman Institute for Advanced Science, the School of Information Sciences, and Computational Science and Engineering in The Grainger College of Engineering.
Professor Petruzzello oversees the Exercise Psychophysiology Laboratory in the Department of Kinesiology and Community Health in the College of Applied Health Science.