Quantifying the effects of luminous properties on human visual and non-visual responses in indoor environments: An integrative lighting network

Artificial lighting is a critical element in indoor environments such as offices, educational facilities, and healthcare settings. However, the dose-response relationships between luminous properties and human responses remain unclear, hindering the scientific determination of lighting parameters in indoor design. This study aims to quantify the impact of luminous properties on human visual and non-visual responses through psychophysical experiments, exploring the correlations and causal relationships between these responses and environmental factors, ultimately establishing a quantitative integrative lighting network. Within the neuroscientific framework of visual and non-visual pathways, this study hypothesizes that 18 luminous properties positively influence five typical human responses: visual preference, visual performance, fatigue, alertness, and emotion. Data were collected from 65 participants (30 males and 35 females) under 28 common indoor lighting conditions by Karolinska Sleepiness Scale (KSS), preference scale, Positive and Negative Affect Schedule (PANAS), d2 Test of Attention, and fatigue scale. Correlation and multiple linear regression analyses identified significant luminous properties associated with human responses and developed optimal regression models that explained 58.7 % of the variance in visual preference, 75.5 % in visual performance, 57.0 % in fatigue, 70.2 % in alertness, and 59.0 % in positive emotion. Further mediation regression analysis revealed the influence of color quality (V1) on alertness was fully mediated by the impact of spectrum on non-visual components (NV), as was the influence of light distribution and illuminance (V2) on emotion. Based on these findings, an integrative lighting network was constructed, providing essential quantitative evidence and guidelines for designing indoor lighting environments to meet diverse functional needs.