Claudia Damiano¹, Erick G. Chuquichambi², Vasiliki Meletaki³, Keaton Bruce⁴, Na Wei⁴, Martin Skov⁵, Anjan Chatterjee³, Dirk B. Walther¹; ¹University of Toronto, ²University of the Balearic Islands, ³University of Pennsylvania, ⁴Temple University, ⁵Copenhagen University Hospital Hvidovre

Curvature is a prominent visual feature that influences aesthetic experiences across various contexts. Particularly within architectural design, understanding how curvature impacts perceptual and emotional responses can inform both the aesthetics field and practical architectural design applications. This study investigated the effects of background and foreground curvature on aesthetic judgements of interior architectural spaces. In an online study using a 2 (Background: curvy vs. angular) x 2 (Foreground: curvy vs. angular) within-subjects design, participants evaluated 56 digitally rendered indoor spaces on measures of liking, beauty, fascination, coherence, hominess, privateness, and time they would spend in the space. Emotional responses to each space were also assessed using a subset of words from the Positive and Negative Affect Scale (PANAS). Our findings revealed that spaces with curved elements were consistently rated higher across multiple dimensions. For liking, spaces with curvy background elements were rated significantly higher than angular ones, F(1, 29) = 6.04, p = 0.02. Spaces with curvy foreground elements were also rated higher, F(1, 29) = 18.95, p < 0.001. Similar effects were observed for beauty, fascination, hominess, and coherence. Interactions between background and foreground curvature highlighted the dominant role of foreground features in shaping aesthetic preferences. Curvy foregrounds consistently drove higher ratings, and their effects were further enhanced when paired with curvy backgrounds, suggesting that foreground curvature plays a leading role in influencing aesthetic responses. Analyses of the PANAS words demonstrated that curvy spaces elicited more positive affect (e.g., “uplifted”) and less negative affect (e.g., “stressed”), supporting the biophilic design hypothesis that nature-like visual features, such as curvy elements, in architecture result in positive affective experiences. These results highlight the benefits of curvy elements in architectural design, and offer insights into how visual features of both background and foreground elements interact to shape aesthetic and emotional experiences.