Despite the prevalent perception that cognitive decline in the aged population is inevitable, researchers with Northwestern University’s SuperAging Project are finding that “excellent memory capacity in late life is a biological possibility.”
A recent study by Rogalski and colleagues1 identified an elite group of individuals 80 years and older who did as well or better on episodic memory tests as healthy individuals who were 20 to 30 years younger. The researchers call them “SuperAgers.”
Emily Rogalski, PhD, lead author of the recent study of 12 SuperAgers and a Research Assistant Professor at Northwestern’s Cognitive Neurology and Alzheimer’s Disease Center (CNADC), explained that the multidisciplinary center is 1 of 27 nationally funded Alzheimer disease centers. The center’s multidisciplinary team follows individuals who have Alzheimer disease (AD) and other dementias but also follows healthy individuals.
As with other National Institute on Aging–supported centers, the CNADC team “does a lot of research on dementia, on what goes wrong with the brain, and on how we can we fix it,” Rogalski told Psychiatric Times. “But we decided to look at things from the flip side and to ask if there are individuals who are able to resist memory loss and who have outstanding memory performance in old age.”
Rogalski said she and others seek to unlock the secrets of SuperAgers’ youthful brains. Their hope is that what they learn may “inform our strategies for improving quality of life for the elderly and for combating AD.”
“The study started as a proof of concept, and we have been successful at identifying individuals aged 80 years and older who have memory performance at least as good as 50-year-olds,” Rogalski said. “They also perform at least in the average range for their age in other domains of cognition.”
The research team, according to Rogalski, recruits healthy individuals 80 years and older who think they have good memories from the CNADC and from the Chicago area through community lectures, referrals, and flyers.
“Typically, individuals who are interested in participating call us and go through a phone screening process where we give some brief cognitive tests that provide us a good idea of whether they will meet the criteria for enrollment,” she said.
Those who might meet the enrollment criteria, Rogalski added, come to the center for 2- to 3-day visits. They undergo additional cognitive testing and are questioned about their personality and medical and family history. They donate blood and undergo an MRI brain scan. They sign up for the longitudinal study, and they return every 18 months.
Of the healthy individuals 80 and older who think they have an outstanding memory, only about 10% qualify as “SuperAgers,” Rogalski said. To be designated SuperAgers, individuals are required to perform at or above average normative values for individuals in their 50s and 60s on the delayed recall scores of the Rey Auditory Verbal Learning Test. They must also perform within 1 standard deviation of the average range for their age and education for the nonmemory measures, according to published normative values based on age, gender, and race/ethnicity.
What’s special about them
Researchers are seeking to identify factors that may contribute to the outstanding memory performance of SuperAgers.
In an initial study published in the Journal of the International Neuropsychological Society,2 the Northwestern team sought to determine whether SuperAgers were resistant to age-related loss of cortical brain volume. The study included 12 identified SuperAgers (average age of 84) from the Chicago area, 10 normally aging elderly participants (average age of 83.1), and 14 middle-aged participants (average age of 57.9).
“We asked a very simple question for the study: if individuals have outstanding memory, do their brains look more like their cognitively matched peers or do they look more like their age-matched peers?” Rogalski said. “We found the brains of SuperAgers looked more like those of the 50-year-olds than those of their age-matched peers. There was no significant cortical thinning or atrophy in the SuperAgers compared with the individuals 20 to 30 years their junior.”
In addition, an area located in the left anterior cingulate was significantly thicker in SuperAgers than in the middle-aged control group by nearly 0.8 mm on average.
“The anterior cingulate is important for attention as well as many other emotional- and higher-order functions,” she said. “So perhaps that is what is helping to keep their memories so strong in old age.”
The findings were “pretty remarkable,” Rogalski said, “since extensive aging research demonstrates that increasing age is associated with decline in memory performance and atrophy of the cortex. Instead, initial research from our team found that among SuperAgers, the integrity of the cortex and memory performance were maintained.”
1. Rogalski EJ, Gefen T, Shi J, et al. Youthful memory capacity in old brains: anatomic and genetic clues from the Northwestern SuperAging Project. J Cogn Neurosci. 2013;25:29-36.
2. Harrison TM, Weintraub S, Mesulam MM, Rogalski E. Superior memory and higher cortical volumes in unusually successful cognitive aging. J Int Neuropsychol Soc. 2012;18:1081-1085.
3. Thomas M. New study examines the mystery of SuperAgers and their super memories. Chicago Sun- Times. August 16, 2012.
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