Effects of Colour Temperature in Classroom Lighting on Primary School Students’ Cognitive Outcomes: A Multidimensional Approach for Architectural and Environmental Design

Primary school students, as the main users of classrooms, are directly affected by the lighting environment, which not only affects their visual comfort but also their cognitive performance. This study investigated the effects of different correlated colour temperature (CCT) levels in classroom lighting on the cognitive performance of primary school students based on a multidimensional evaluation combining physiological signals (EEG and EDA) and subjective assessment. In this study, 53 subjects aged 10–13 years old from a primary school in Anshan City were used in a controlled experiment under five CCT conditions (3000 K, 4000 K, 5000 K, 6000 K, and 7000 K) at a constant illumination level of 500 lx. EEG and skin conductance (SC) signals were collected and subjective perceptions of visual comfort and fatigue were assessed while cognitive tasks were carried out. The results showed that students performed best cognitively at a colour temperature of 4000 K, with the lowest EEG absolute power (AP) (p < 0.01) and highest comfort (p < 0.05). Females were more sensitive to colour temperature changes and showed better cognitive performance in cooler colour temperature conditions, while male students performed better in warmer light conditions (p < 0.01). The above findings suggest that optimising the CCT of classroom lighting enhances students’ cognitive functioning and comfort, providing empirical support for lighting design guidelines in educational environments.