Science Advances: Brain Activity May Predict Alzheimer's Disease Years Before Symptoms Appear

The researchers compared brain scan data from 180 people over the age of 75 who had exceptionally good memory for their age with data from 110 patients with Alzheimer's disease. They identified characteristic differences in the activity and interactions of various brain regions.

Based on these findings, the researchers developed the ARC system, which assesses whether a person's brain activity resembles the profile of individuals resistant to age-related cognitive decline or, conversely, the pattern associated with Alzheimer's disease. The system distinguished between the two groups with an accuracy of approximately 85%.

The researchers then tested the system using data from more than 1,300 people aged 55–70 who showed no signs of cognitive impairment at the time of assessment. Participants with a more pronounced “Alzheimer's-like” profile subsequently experienced faster declines in memory, attention, and other cognitive abilities. Some also developed characteristic brain changes and were diagnosed with Alzheimer's disease. In certain cases, follow-up lasted up to 12 years.

According to the authors, the ARC system was at least as effective at predicting cognitive decline as some existing biomarkers and genetic indicators. Combining these measures further improved predictive accuracy.

In the future, the researchers hope to determine whether unfavorable patterns of brain activity can be modified through cognitive training or transcranial magnetic stimulation. However, these approaches have not yet been tested as methods of preventing Alzheimer's disease.

The authors emphasize that the ARC system is not yet intended for diagnostic use and cannot reliably predict the outcome for any particular individual. Its potential value lies in identifying risk at an early stage, before cognitive impairment becomes apparent.