New research indicates that older adults may be considerably better at recognizing day-to-day changes in their own cognitive abilities than previously assumed. In a study of 162 older adults who expressed concerns about cognitive changes despite performing normally on conventional screening, participants used smartwatches four times daily for one week to rate their mental sharpness and mood before completing short cognitive tests. When individuals rated themselves as less mentally sharp than their personal average, their objective test performance also declined, an association that persisted after researchers accounted for mood, age and other factors. The findings raise the possibility that smartwatches and similar consumer technology could eventually supplement traditional office-based cognitive testing by providing physicians with repeated measurements of how patients actually function during ordinary life.
Key Takeaways
- Older adults demonstrated a meaningful ability to recognize fluctuations in their own cognitive performance, with below-average self-ratings of mental sharpness corresponding to poorer performance on objective cognitive testing.
- Smartwatch-based monitoring could address an important limitation of conventional cognitive screening by collecting repeated measurements during everyday activities instead of relying primarily on occasional examinations conducted in controlled clinical environments.
- The technology is promising but remains an investigational monitoring approach rather than a dementia diagnostic tool; researchers need longer-term studies to determine whether changes recorded by wearables can reliably predict mild cognitive impairment, Alzheimer’s disease or other forms of dementia.
In-Depth
A new study suggests older adults may have a more reliable sense of their moment-to-moment cognitive performance than conventional clinical practice has often assumed. Researchers followed 162 older adults, who reported concerns about cognitive changes but still scored within normal limits on standard screening. For one week, participants received four daily smartwatch prompts asking them to rate their mental sharpness and mood before completing brief cognitive exercises.
The central finding was when participants believed they were less mentally sharp than their own usual level, their measured cognitive performance also tended to be lower. Importantly, the relationship remained after researchers accounted for mood, age, contextual factors and practice effects. This matters because subjective memory complaints have sometimes been discounted as products of anxiety, depression or unreliable recollection.
The research also highlights a weakness in traditional cognitive assessment. A short examination conducted periodically in a quiet medical office captures only a narrow snapshot. Repeated assessments during ordinary life may reveal fluctuations and trends that an occasional appointment cannot.
Smartwatches could therefore become useful monitoring instruments rather than mere fitness accessories. Combined with longer-term data, they may eventually help physicians identify people who warrant more thorough evaluation before impairment becomes obvious.
The findings should not be overstated. A week of smartwatch observations cannot diagnose dementia, and researchers must establish whether these patterns predict decline over months or years. The prudent approach is to view wearable monitoring as a promising supplement to clinical judgment, not a replacement for physicians, neurological testing or diagnostic procedures.

