Digital biomarkers from wearable devices could revolutionise brain health monitoring, offering continuous, low-burden tracking of cognition and mood in everyday life. Researchers say this approach may help detect early changes in brain function before symptoms appear.
Brain health encompasses cognitive abilities, emotional regulation, and mental well-being. Traditional monitoring relies on time-intensive assessments that are often sporadic and burdensome. Passive, wearable-based technologies could transform this landscape by capturing real-world, continuous data.
The study followed 82 cognitively healthy adults over 10 months, collecting both passive and active data on behaviour, physiology, and environmental exposures. Wearables captured metrics such as movement, heart rate, and sleep patterns, while mobile devices tracked environmental factors. Data quality was exceptionally high, with 96% daily coverage, enabling robust analysis.
Using artificial intelligence, researchers predicted 21 cognitive and mental health outcomes. Patient-reported outcomes proved more predictable than performance-based tasks, suggesting that everyday experiences provide meaningful insight into brain health.
Feature-importance analyses showed that environmental exposures, like light, location, and ambient conditions, explained differences between participants. Physiological and behavioural rhythms, such as heart rate variability and activity patterns, tracked changes within individuals over time. Together, these signals offer a rich portrait of both inter- and intra-individual brain health variability.
The findings demonstrate that digital biomarkers collected passively from wearables can reliably capture cognitive and emotional changes in real-world settings. This approach could support large-scale population monitoring, early detection of cognitive decline, and personalised interventions.