Non-linear Relationships Between Daylight Illuminance, Individual User Characteristics, and Cognitive Performance in an Educational Interiors

Daylight is a critical factor in educational interiors, yet its impact on cognitive performance is often overlooked in favor of energy efficiency.This study investigates the relationship between daylight illuminance and cognitive performance within a university design studio, focusing on the non-linear interactions between seating positions as daylight illuminance level (K1-K4) and individual user characteristics.An experimental field study was conducted with undergraduate interior architecture students using the Raven Standard Progressive Matrices Test (RSPM) across five complexity levels (Sets A-E).Results indicate that cognitive performance is not a direct consequence of illuminance alone but emerges from complex interactions with gender, visual status, chronotype, and sleep duration.Findings challenge uniform lighting standards by revealing multiple optimal conditions; while higher illuminance improved performance for specific groups, moderate or lower levels were more favorable for others.The study highlights the necessity of shifting toward user-sensitive and spatially adaptive daylight strategies.By demonstrating the non-linear nature of environmental interaction, it contributes to design-oriented discussions aimed at enhancing both cognitive success and environmental satisfaction in learning environments.