Aging In Arizona, Part 1: UA Researchers Tackle Alzheimer’s Disease, Dementia

By Sara Hammond
Published: Monday, July 11, 2016 - 8:20am
Updated: Tuesday, July 12, 2016 - 8:57am
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(Photo by graphicstock.com)
The brain is the most complex human organ.

More Arizonans are living longer because medical advances in heart disease, cancer and diabetes keep their bodies going. But what about their brains? In our five-part series, Aging In Arizona, we explore what researchers are learning about the aging brain, the risks of developing dementia and latest treatments for it.


Approximately 16 million Americans are expected to battle Alzheimer’s disease by 2050. That amounts to a public health crisis as Baby Boomers near the end of their life expectancies.

In Arizona, a retirement mecca, researchers are exploring healthy brain aging as doctors better manage heart disease and other chronic ailments. At the University of Arizona, neuroscience is a research priority and scientists in several departments and centers are focusing on aging and the brain.

Scientists have struggled to understand what causes Alzheimer’s disease ever since it was first identified in 1905. UA researchers are focusing on menopause and other reproductive cycle transitions in women and their effect on the brain’s neural circuits as a clue to the origin of Alzheimer’s and other degenerative brain diseases.

Others at UA are working to figure out how to keep the brain as healthy as it can be to a person’s oldest age.

Carol Barnes is director of the Evelyn F. McKnight Brain Institute at the University of Arizona. Her research focuses on how the brain changes during the aging process and what the functional consequences of these changes are on information processing and memory.

"Aging is not a disease. Aging is a normal developmental process,” said Barnes.

Barnes said in the mid-20th century, it was assumed that when we aged, we lost brain cells, our memory diminished and we became demented.

“Today we know you don’t lose many brain cells as you age. There are many changes that occur in the aging brain that seem to be adaptive rather than negative," Barnes said.

The brain is the most complex human organ. It is always developing, always changing.

“Our brain, even from the earliest years, is continuously evolving and changing and adapting and with time our memories do change with age. And there are real brain changes that are responsible for that and it’s not that we lose cells," said Barnes. "What happens is that the brain plasticity and the brain connections are altered that make a laying down of memories harder. So it’s not that aging is a degenerative process. Your cognition, your memory does change but things like vocabulary actually get stronger as you age, you continue to collect words throughout your life. So it’s not all downhill.”

The brain’s cellular connections, called synapses, are what enable memory formation and storage. Barnes said sleep allows the brain to replay the day’s accumulation of information and lets the cortex lay down what was important to begin memory formation.

Barnes said perhaps humans shouldn’t remember everything.

“Forgetting is good. There are people who can’t forget easily and that is a very difficult state of affairs. You want to let things go that aren’t as important and hang on to those that are. Typically, you recall something and you retrieve something you’ve retrieved before in your life. Maybe you’ve learned most of the things you need to learn over your lifetime and you don’t want to force out by cramming in all sorts of new things. So maybe it should be harder to put some new things in because you’ve already learned the most critical ones for your survival.”

Barnes said we all are not destined to get Alzheimer’s or become demented.

“If you look at all people in the US in a random sample, if you look at all the people over 71 years of age, 14 percent of us will be demented. That means 86 percent of us are not demented. We should have a very positive outlook about aging. It’s not inevitable at all that you become demented.”

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