Older adults asked to rate how sharp they felt at random moments during the day were remarkably accurate, according to new research from UC Davis Health that used smartwatches to capture both self-ratings and objective cognitive testing in real time. The self-assessments lined up closely with how people actually performed.
The study followed 162 participants with an average age of about 72. All of them had noticed changes in their memory or thinking, but all scored within normal limits on standard cognitive tests before the study began - a group that conventional office-based assessment would likely wave through as unremarkable.
Sarah Tomaszewski Farias, the neuropsychologist who served as senior author, said the aim was to compare how people perceive their own ability to think with how they perform on objective measures. She noted that the close alignment between the two could open a path to detecting cognitive decline and Alzheimer's risk earlier than standard testing allows. Tomaszewski Farias is a professor of neurology at UC Davis, directs the California Alzheimer's Center of Excellence, and leads the clinical core of the NIH-funded UC Davis Alzheimer's Disease Research Center.
The practical appeal here is timing. A single clinic visit captures one snapshot on one day, while repeated smartwatch prompts sample thinking as it fluctuates across ordinary life. If subjective complaints from people who still test normally turn out to carry real signal, that reframes a symptom clinicians have often had trouble acting on.