Brain changes linked to Alzheimer's disease may begin at least seven years before amyloid plaques become visible on current PET scans, according to a new study from the University of Oslo.
The Research
Researchers followed healthy older adults for nearly 20 years, conducting regular MRI scans to track brain structure over time. They identified participants who later developed amyloid plaques—a hallmark of Alzheimer's—and compared their earlier brain scans with those who never developed plaques.
The team, led by James Michael Roe (formerly at the Center for Lifespan Changes in Brain and Cognition, now at Cercare Medical) and professor Anders Martin Fjell, found significant structural differences in the brains of those who later showed plaques, appearing at least seven years before the plaques were first detectable. The findings were published in Nature Neuroscience.
Specifically, they observed changes in brain volume and cortical thickness in regions typically affected by Alzheimer's, even when amyloid levels were still normal. This suggests that damaging processes may be underway long before the current gold-standard biomarker appears.
Why It Matters
This discovery challenges the assumption that amyloid plaque buildup is the very first step in Alzheimer's pathology. If brain changes occur earlier, it could open a window for earlier intervention and monitoring. For individuals concerned about cognitive health, this means that future screening might identify risk factors years before symptoms or even before plaques are visible.
It also highlights that Alzheimer's is a complex disease likely involving multiple biological pathways, not just amyloid accumulation.
What You Can Do
While these findings are not yet a clinical test, they underscore the importance of maintaining brain health throughout life. Regular physical exercise, a balanced diet, mental stimulation, and social engagement are all associated with better cognitive aging. Consider tracking your cognitive baseline with validated tools like the free IQ test at iqgenio.com to monitor changes over time.
Source: ScienceDaily Mind & Brain
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