In the recent presidential debate, the age of the candidates—78 and 81—sparked widespread discussion about aging and cognitive health, especially after some viewers perceived President Joe Biden as appearing “old and frail.”
This has led to a renewed focus on understanding what happens to the brain as we age. To provide a clearer picture, we consulted experts on aging and cognitive health.
The Shrinking Cortex: A Key Factor in Cognitive Aging
One significant change in the aging brain is the shrinkage of the cortex, the brain’s outer layer, where brain cells reside. “The cortex is crucial for our thinking and communication,” says Emily Rogalski, a neurology professor at the University of Chicago and director of its Healthy Aging & Alzheimer’s Research Care Center. She explains that the cortex is similar to the bark on a tree and is essential for memory, attention, and executive functions. Memory performance peaks in our 20s or early 30s, and as the cortex shrinks with age, these cognitive abilities often decline.
Normal Age-Related Memory Loss
Patricia Boyle, a professor of psychiatry and behavioral sciences at Rush University, emphasizes that age-related memory loss is a normal part of aging. “Most people experience mild forgetfulness as they age, which is not necessarily indicative of a serious cognitive issue,” she explains.
Common signs of normal cognitive aging include occasionally making poor decisions, missing a monthly payment, losing track of time, struggling to find the right words, and misplacing items around the house.
Accelerated Brain Shrinkage in Older Age
Brain shrinkage, particularly in the frontal lobe and hippocampus, accelerates around age 60, impacting cognitive functions. Rogalski explains that aging increases the risk of diseases due to the body’s wear and tear, and unlike other body parts, the brain cannot be replaced.
Dr. John Rowe, a professor of health policy and aging at Columbia University, notes that about 12% to 18% of people over 65 experience mild cognitive impairment (MCI), which can progress to dementia in about 10% of cases annually.
The Concept of Superagers
Despite the challenges of aging, some older adults maintain high cognitive performance, known as superagers. Rogalski’s research as part of the SuperAging Research Initiative reveals that superagers’ brains resemble those of much younger individuals, with less cortical shrinkage and thicker anterior cingulate cortexes (ACC).
This region is associated with motivation, decision-making, and emotional regulation. Superagers also have an abundance of von Economo neurons, which may contribute to their cognitive resilience.
Factors Influencing Cognitive Health in Old Age
Rowe’s research at Harvard University on successful aging found that lifestyle factors such as social connections, educational attainment, and financial security significantly influence cognitive health in older adults.
The study highlighted that cognitive abilities vary widely among 80-year-olds, with some showing signs of dementia, others maintaining high cognitive function, and many in between.
Embracing Aging and Its Opportunities
Rogalski emphasizes the importance of changing our perceptions of aging. She cautions against removing daily responsibilities from older adults, as activities like washing dishes and moving around are beneficial for maintaining physical and cognitive health.
Engaging in social activities, learning new skills, and practicing fine motor tasks are essential for keeping the brain active.
In summary, while aging inevitably brings cognitive changes, the extent and impact of these changes vary widely. Understanding and supporting cognitive health in older adults requires a nuanced approach, recognizing both the challenges and the opportunities that come with age.
As Rowe points out, “We cannot generalize about the cognitive abilities of 80-year-olds; each individual’s experience is unique.”
By focusing on these insights and adopting a balanced view of aging, we can better support the cognitive health and well-being of older adults. For more information on cognitive health and aging, visit Clarah.co.
