How Background Colour Shapes Digital Text-Information Processing: A fNIRS-Eye Tracking Study

As digitalization advances, colour in human-computer interaction now fundamentally shapes digital text processing beyond aesthetics. However, the background colour's impact on text information processing under controlled luminance conditions remains underexplored. This study employed a multimodal approach combining functional near-infrared spectroscopy (fNIRS), eye tracking, behavioural performance and subjective reports to systematically examine colour’s effects on text comprehension. Key findings demonstrated that green elicited higher activation in the left frontal pole area (FPA-L), right Broca’s area (Broca-R), and the left dorsolateral prefrontal cortex (DLPFC-L), corresponding to the highest accuracy. In contrast, red and blue reduced brain activation, arousal levels, accuracy, and prolonged average visit duration. Correlational analyses revealed critical underlying mechanisms, showing that colour difference negatively correlated with brain activation (DLPFC-L, Broca-R), pupil diameter, and subjective reports. These findings highlight the importance of colour in text information processing and provide actionable insights for optimizing colour choices in digital interfaces.