Preserving the power of decision

New UF researcher looks at behavior to find the missing pieces to memory loss.

By John Pastor

Memory researcher Jennifer Lynn Bizon, PhD, is keenly aware that people’s brains age differently.In her life, she watched as one of her grandmothers coped with worsening dementia for 12 years. Yet she saw how her other grandmother remained sharp even at age 87, polishing off crossword puzzles that were beyond the reach of much younger people.

Even today, the question of how two people who were so much alike could age so differently still influences her thinking. A neuroscientist at the UF College of Medicine supported by the McKnight Brain Research Foundation, Bizon works to understand the biological and environmental factors that distinguish people who age successfully and maintain strong memory function.

Alongside threats such as Alzheimer’s disease, the consequences of normal aging, such as simple memory loss, have not been fully appreciated. Yet, about 88.5 million U.S. residents are expected to be 65 and older in 2050, more than double the number today.

“Ideally, we would like to identify at-risk individuals early enough to take advantage of the optimum treatment window, before they actually start to exhibit severe impairment,” Bizon said.

A recent arrival to UF from Texas A&M University, where she was an assistant professor of psychology and neuroscience, Bizon’s goal is to develop diagnostics for age-related cognitive dysfunction and provide a foundation for therapies that will prevent mental decline or — better still — restore clarity.

By tracking when impaired and non-impaired rodents display differences in mental function, she can track the changes in brain signaling and gene expression at the root of memory loss.

“She’s developed techniques to isolate changes in cognitive function, and she can use these techniques to detect memory changes more precisely than we ever could before,” said Thomas Foster, PhD, the Evelyn F. McKnight chair for research on aging and memory at UF. “The higher level of sensitivity of her techniques offers a window to changes in executive function — the decision-making that occurs when we tap into what we’ve just learned. That is important if we are going to develop therapies for memory deficits or diagnostics to detect cognitive changes at an earlier stage in humans.”

Generally, as people grow older, certain parts of their brains shrink. Arteries in older brains also become narrower, limiting blood and oxygen supplies for cells. Gradually, neurons lose their ability to communicate.

For many people, this results only in occasional memory lapses, such as forgetting keys or blanking on a person’s name. But others experience significant difficulty processing information and problems making decisions. When those losses degrade the ability of people to live independently, the health impact explodes.

“Dr. Bizon understands that cognitive aging and its associated decline is different than declines that take place because of disease processes,” said J. Lee Dockery, MD, a trustee of the McKnight Brain Research Foundation and a former interim and executive associate dean of the College of Medicine. “She has also discovered there are different processes used by elderly people that are not used by younger people — the nerve cells formed later in life function differently. Her research is providing new information about cognitive aging and how to help people age successfully.

“If we can enable more people to manage their finances, savings and other resources — in other words handle the neuroeconomics of their lives — we can help more people remain functional in their homes,” Dockery said. “That is a critically important for the future of health care.”