higher indoor CO2 levels linked to poorer delayed memory recall in older adults
Exact: r = -0.64
Higher indoor CO2 levels associated with poorer delayed memory recall in older adults
In a study of 39 community-dwelling older adults, continuous 24/7 sensor-based CO2 measurements in the home were significantly correlated with delayed recall scores (r = -0.64). Higher CO2 levels—indicative of poorer indoor air quality—were linked to worse memory performance, highlighting indoor air quality as a potential modifiable risk factor for cognitive decline in aging populations.
Additionally, increased evening light exposure correlated with higher stress (r = 0.75), higher CO2 levels were associated with poorer delayed recall (r=-0.64), and higher humidity was linked to increased insomnia severity (r = 0.64).
Related findings
40–80%
prediction quality for cognitive symptoms varied widely across participants and symptom types
F1 scores for cognitive symptom prediction ranged from 40% to 80% across participants
Tao Zang et al., 2026, Indoor Environments
>70%
machine learning model predicted cognitive symptoms from office environment data with reasonable accuracy
XGBoost model accuracy for predicting cognitive symptoms generally exceeded 70%
Tao Zang et al., 2026, Indoor Environments
up to 23%
smart adaptive interventions could raise studio environmental quality scores
Smart adaptive interventions could improve studio environmental quality scores by up to 23%
2026, Zenodo (CERN European Organization for Nuclear Research)
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