A new collaborative study led by UF neuroscientists Sara Burke, Ph.D., and Marcelo Febo, Ph.D., gives insight into why brain networks become vulnerable in old age. In addition to helping guide future research into cognitive aging, the study’s identification of a mechanism associated with cognitive changes could be relevant to inform future research into neurodegenerative conditions such as Alzheimer’s disease, the investigators said.
The rodent-model study, published in the journal eNeuro, links micro-scale changes in individual brain cells to large-scale changes in brain networks — a finding that could potentially help in the development of therapies to improve cognitive function in the elderly.
To date, researchers have been seeking to understand how changes within individual brain cells are related to altered functional connectivity in older adults. “Functional connectivity” is a term to explain that higher cognitive function requires different regions of the brain to be active at the same time.
In the study, which used resting-state functional magnetic resonance imaging, or fMRI (a non-invasive technique commonly used in humans), investigators found that old rats that were cognitively trained to complete two tasks simultaneously — or “multitask” — experienced changes in the brain’s patterns of functional connectivity. Assessing the way brain networks are functionally connected can predict cognitive abilities.
In addition to fMRI, the research team used cellular imaging of the expression of a gene that is critical for the brain’s ability to change in response to experience.
“Importantly, in rats that could not successfully learn to multitask, these changes in functional connectivity were related to gene expression within individual neurons in a region of the brain that is involved in habit formation, known as the dorsal striatum,” said Burke, an associate professor of neuroscience. “This work opens a new avenue for linking large-scale brain networks to cellular mechanisms.”
(This post has been updated to provide additional context to the references to Alzheimer’s disease.)