A predictive framework for assessing working memory and attention under combined indoor thermal and lighting conditions using physiological data

While thermal and lighting conditions independently influence comfort and cognition, their combined effects on cognitive functions and physiological responses remain unclear. This study investigated the combined effects of indoor temperatures (22°C, 26°C), lighting intensities (150, 800 lx), and correlated color temperatures (CCT) (5200, 2600 K) on working memory, sustained attention, and physiological responses. A predictive framework was developed to estimate cognitive performance using physiological indicators (heart rate, pupil size, and skin temperature), environmental conditions, and gender. Results showed that working memory performance was higher at 22°C, while sustained attention improved at 26°C. Both cognitive functions benefited from warmer lighting (2600 K), and working memory was enhanced under higher illuminance (800 lx). Interaction effects among temperature, lighting intensity, and CCT differed by cognitive domain. Working memory was positively correlated with heart rate and negatively correlated with pupil size and skin temperature, while sustained attention was negatively assiciated with skin temperature. The predictive framework achieved 80.4% accuracy for working memory and 61.6% for sustained attention. These findings demonstrate the multidimensional and task-dependent nature of combined thermal and lighting effects on cognitive performance, highlighting physiological signals, gender, and environmental factors as key predictors of cognitive performance.