Science Begins to Unlock the Secrets of Brains that Age Well

Researchers are investigating how some older adults are able to maintain elevated levels of cognition and memory as they age. | Northwestern University

Improvements in medicine, science and lifestyles continue to add years to the average lifespan. In the 1970s, living to 100 got you a birthday card from President Richard Nixon, said Dr. Claudia Kawas, professor of neurology and associate director of the Institute for Memory Impairments and Neurological Disorders at the University of California, Irvine.

But that stopped decades ago when the ranks of centenarians grew. Children born in the United States today are expected, on average, to live to age 103, and by the middle of the century, the U.S. will have 8-10 million people age 90 and older, she said.

“The sad thing is, we’ve added more years than we’ve added quality,” Kawas said during a press briefing on Feb. 17 at the AAAS 2018 Annual Meeting in Austin, Texas. About two-thirds of people over age 90 have dementia or some less severe cognitive loss. But, “there’s a remarkable core of individuals we see who maintain excellent cognitive skills and often motor skills,” she said.

As the lead investigator of “The 90+ Study,” Kawas and other researchers have been testing and tracking subjects for the past 15 years to find differences in their brains and lifestyles that might be responsible.

One of Kawas’ most interesting findings is that when her team began autopsying the brains of those who were aging well and exhibiting no signs of dementia, about 40 percent had “full-fledged” Alzheimer’s Disease. “And the question is: ‘Why are they still thinking well?’” Kawas said.

While they don’t have definite answers, besides having good genes, Kawas said, the answer is probably a combination of being resilient to Alzheimer’s Disease and also that they did not develop other dementia-causing conditions, such as microscopic infarctions that occur when blood flow is blocked from certain regions of the brain and hippocampal sclerosis, which causes neuron loss. Both conditions almost guarantee dementia.

Another study focused on “super-agers,” 80 years or older who have memory performance as good as people in their 50s or 60s and examines lifestyle differences. The brains of the super-agers showed less cortical thinning, or neuron loss in certain areas, said lead researcher Emily Rogalski, research associate professor at the Cognitive Neurology and Alzheimer’s Disease Center, Northwestern University Feinberg School of Medicine in Chicago. In fact, their brains were physically more similar to the brains of people aged 50-60 than their 80-year-old peers.

The super-agers also had developed increased thickness in an area of the brain associated with decision-making, impulse control and emotions and other functions that was not found in the brains of their peers or of healthy younger people.

Lifestyle surveys showed super-agers also were more likely to report valuing close, meaningful relationships with people in their lives. “There are brain benefits of having good friends,” Rogalski said.

However, the researchers are not sure if the super-agers have more close friends or family members that they’re communicating with or wider social circles. Rogalski said she plans to study that, as well as how relationships benefit brain health.

For those who need some memory or other cognitive improvements now, there may soon be a video your doctor can prescribe. Adam Gazzaley, professor of neurology, physiology and psychiatry at the University of California, San Francisco and executive director of Neuroscape, has developed video games designed to improve memory, attention and learning that adjust to a player’s performance and focus on different cognitive systems.

The games are being tested in elderly people with Alzheimer’s Disease or Parkinson’s Disease, as well as in children diagnosed with attention-deficit hyperactivity disorder to gain FDA approval as a treatment. 

Earlier trials showed that the games could improve multi-tasking using the game in healthy 70, 80, and 90-year-olds, Gazzaley said, and that the games created other cognitive improvements. He is now working on incorporating new technologies that will allow players to use their bodies as they play, while the game tracks their heart rate as well as cognitive performance. “I’m interested in new tools to help improve neuroplasticity,” Gazzaley said.

There are other reasons to be hopeful we can all age better. Data show that the risk of developing dementia has declined slightly in the past decades, Kawas said, which she attributes to people improving their lifestyles: eating better, exercising more, trying to minimize stress. Research has also showed better cognitive performance in people who usually get at least 8 hours of sleep.

Her advice? “Do what your mother told you,” Kawas said.

[Associated image: Northwestern University]