Stanford Medicine researchers identified brain activity patterns associated with Alzheimer’s risk years before memory problems appear.
In more than 1,300 cognitively healthy adults, the patterns helped predict later cognitive decline and Alzheimer’s diagnoses.
The experimental scoring system is not a diagnostic test, and researchers have not established whether changing these patterns can prevent the disease.
A new Stanford Medicine-led study suggests that patterns of brain activity could offer an early warning of Alzheimer’s disease, years before people develop noticeable memory problems.
Published in Science Advances, the research examined how different brain regions function together during rest. Scientists developed a score that distinguished patterns associated with exceptional memory in old age from those associated with Alzheimer’s.
To build the model, researchers compared brain scans from older adults with Alzheimer’s with scans from “super agers,” people whose memory remains unusually strong. The initial analysis included 290 participants, with results replicated in a separate group of 143.
The resulting measure, called the Alzheimer’s resilience-vulnerability connectome, or ARC, captured differences in networks involving the prefrontal cortex, temporal regions and insula. These brain networks helped distinguish the two groups.
What the study found
Researchers then applied the model to two groups totaling 1,315 adults who had no cognitive impairment. Although participants initially showed comparable cognitive abilities, their subsequent paths differed.
People with more Alzheimer’s-like brain patterns experienced faster cognitive decline, greater accumulation of amyloid-beta — a protein associated with Alzheimer’s — and a higher risk of progressing to the disease. People with patterns resembling those of super agers generally had more favorable outcomes.
Follow-up extended as long as 12 years, although most datasets covered about five to six years. The warning signs were detectable through brain imaging, meaning participants could perform normally on memory tests while already showing patterns associated with future decline.
What it means
The findings could eventually help researchers identify people for prevention studies and test whether interventions strengthen the brain’s resilience. However, the study establishes an association between brain patterns and later outcomes; it does not prove those patterns cause Alzheimer’s.
Stanford researchers emphasized that an ARC score is a snapshot of risk, rather than a prediction of an inevitable diagnosis. The team plans to investigate whether cognitive training changes the score, but whether such changes would prevent or delay Alzheimer’s remains unknown.