Adaptive and natural daylighting effects on personalised cognitive recovery in public office buildings in Ghana

Purpose Despite the global recognition of daylighting as energy efficient, there remains a significant gap in appreciating its cognitive impacts in public office buildings in tropical regions. This study aims to assess the effects of adaptive and natural daylighting on cognitive function, fatigue, visual comfort and user satisfaction in public office buildings in Ghana. Design/methodology/approach A quasi-experimental, repeated-measures design was used across 15 public office buildings in Ghana. A total of 523 office staff completed structured surveys three times daily over five working days, resulting to 7,845 repeated observations. Linear mixed-effects regression was used for perceived cognitive clarity and environmental satisfaction, while ordinal logistic regression was used for the ordinal outcomes of visual comfort and mental fatigue. Lighting condition and time of day were included as predictors. Findings Adaptive lighting considerably improved visual comfort (β = 0.622, p < 0.001), reduced mental fatigue (β = −0.525, p < 0.001) and improved perceived cognitive clarity (β = 0.665, p < 0.001). Natural daylight also showed positive but minimal effects. Time-of-day trends showed increased perceived fatigue in the afternoon and a morning peak in perceived cognitive clarity. Adaptive systems uniquely moderated these fluctuations, consistently improving environmental and user satisfaction. Practical implications The findings suggest that adaptive lighting may be considered in office design and future building-performance frameworks in Ghana and other sub-Saharan African contexts with similar conditions. Rather than suggesting immediate regulatory requirements, the evidence requires further pilot implementation, post-occupancy evaluation and performance-based assessment of adaptive lighting in public offices. The findings specifically relate to perceived cognitive clarity, mental fatigue, visual comfort and environmental satisfaction. Other variables like productivity, economic returns and occupational-health outcomes were not directly measured. Originality/value This study examines adaptive lighting as a human-centred intervention in public office environments in Ghana. By comparing adaptive lighting, natural daylight and standard artificial lighting using repeated subjective measures, this study contributes field-based evidence on perceived cognitive clarity, fatigue, visual comfort and environmental satisfaction in an underrepresented regional context.