Visual psychological performance of different flattened bamboo boards based on semantic differentiation method and event-related potential.

Flattened bamboo boards are increasingly used in interior environments; however, their influences on users' perceptual and cognitive responses remain insufficiently understood. Using a sample of 25 participants, this study investigated the visual psychological impressions and neurocognitive processing associated with three types of flattened bamboo boards by integrating Semantic Differential (SD) evaluations with event-related potential (ERP) measurements. ERP analyses focused on the P300 component (300-500 ms) across frontal, central, parietal, and occipital regions. The results revealed clear perceptual and neural distinctions among the board types. The inner board consistently elicited the most positive perceptual impressions, being associated with naturalness, warmth, comfort, and delicacy, and was processed with the lowest cognitive load. In contrast, the outer board tended to be perceived as more artificial and decorative and evoked the highest P300 amplitude and longest latency, indicating greater cognitive effort and evaluative complexity. The bamboo outer layer board exhibited a more neutral and heterogeneous perceptual profile, with balanced evaluations of naturalness versus artificiality and exquisiteness versus roughness, while being more frequently associated with coolness and showing greater inter-individual variability in subjective evaluations. ERP analyses further demonstrated significant differences in P300 amplitude and latency across board types. While parietal P300 amplitudes differed significantly (F = 5.226, p = 0.049), latency differences were more pronounced in the central, parietal, and occipital regions (all p < 0.01). Gender-related differences were observed in both subjective ratings and neural responses, with male participants showing higher cognitive engagement during visual evaluation. Overall, these findings demonstrate that variations in bamboo surface appearance can systematically influence affective appraisal and cognitive load, providing empirical support for evidence-based material selection and interior design.