Scientists are finding that the shape of your brain could say a lot about your future health. A new study suggests that subtle shifts in brain structure—how it expands or contracts over time—may signal early warning signs of dementia, long before memory loss or confusion begin.
The research, led by neuroscientists from the University of California, Irvine (UC Irvine) and the University of La Laguna in Spain, examined thousands of MRI scans to investigate how aging affects the brain’s physical structure. What they found points to a possible new way to identify cognitive decline early, using shape patterns instead of waiting for visible symptoms or severe tissue loss.
Brain shape and dementia risk
“Most studies of brain aging focus on how much tissue is lost in different regions”, said neuroscientist Niels Janssen from the University of La Laguna. “What we found is that the overall shape of the brain shifts in systematic ways, and those shifts are closely tied to whether someone shows cognitive impairment”.
The team analyzed more than 2,600 brain scans from adults aged 30 to 97, tracking both structure and performance on reasoning and memory tests. They discovered that shape changes don’t happen evenly. Some regions—especially those at the back of the head—tend to shrink faster, while others expand slightly with age.
This uneven pattern was much more pronounced in people who showed early signs of cognitive decline. Researchers also identified one region in particular that seems especially vulnerable: the entorhinal cortex, a key memory hub deep in the brain. This is the same area where Alzheimer’s disease often begins, as toxic proteins like tau and beta-amyloid start to accumulate.
According to UC Irvine neuroscientist Michael Yassa, these gradual shape shifts could create mechanical stress on the entorhinal cortex, making it more susceptible to damage. “If the aging brain is gradually shifting in a way that squeezes this fragile region against a rigid boundary, it may create the perfect storm for damage to take root”, Yassa explained.
The findings open a new path toward early detection. Instead of waiting for memory problems to appear, doctors could one day use shape-based imaging patterns as an early screening tool before cognitive decline becomes visible.
How to protect your brain as you age
While researchers continue to study how brain shape and dementia are connected, decades of evidence already point to lifestyle habits that protect brain health and slow cognitive decline. Here are a few:
- Stay mentally active. Reading, learning new skills, or playing strategy games can strengthen your neural connections.
- Exercise regularly. Physical activity improves blood flow to the brain and supports the growth of new neurons.
- Eat a brain-friendly diet. The Mediterranean and DASH diets—rich in fruits, vegetables, whole grains, fish, and healthy fats—are consistently linked to lower dementia risk.
- Sleep well. Deep sleep helps clear toxic proteins from the brain, including the same ones that build up in Alzheimer’s.
- Manage cardiovascular health. High blood pressure, diabetes, and smoking can all increase the risk of dementia.
- Stay socially connected. Strong relationships and frequent social engagement stimulate multiple brain regions tied to memory and emotional regulation.
Scientists still have a lot to learn about how structural brain changes translate into cognitive decline, but paying attention to your brain health early is your best strategy for building a resilient brain for years to come.