Summary:

- The article discusses new research on Alzheimer's disease, which suggests there is a "quiet phase" of the disease before symptoms appear.
- Scientists have found that changes in the brain associated with Alzheimer's can begin up to 20 years before the onset of cognitive decline and memory loss.
- This quiet phase provides an opportunity for early intervention and treatment, as it allows for the identification of individuals at risk of developing Alzheimer's before the disease progresses to the symptomatic stage.