Individual differences in the curvature effect with abstract stimuli and interior design

Visual preference for smooth curvature, as opposed to angularity, has been documented for a variety of stimuli, participant groups, primate species, and different tasks. However, the universality of preference for curvature has been questioned in a recent meta-analysis of 61 studies (Chuquichambi et al., 2022). Among other factors, individual differences as well as the type of stimuli mod- erate the effect. In this research we examined preference for curvature in three different groups of participants using abstract stimuli and pictures of interior design. Specifically, we examined visual preference for curvature in high func- tioning autism (ASD = 16), in matched (for age, gender and IQ) neurotypical individuals (NT = 20) and in a group of quasi-expert students of design (QE = 24). We employed abstract shapes with different contours (angular vs. curved), and a set of coloured lines (angular vs. curved) presented through a circular or square aperture. Finally, we showed interior design environments varying for Appearance (curvilinear vs. rectilinear), Ceiling (high vs. low) and Space (enclosed vs. open). Participants indicated like or dislike and whether they would enter, or exit, the presented spaces if these were real rooms (approach/ avoidance). Preference for curvature was confirmed with abstract stimuli with all groups of participants. However, the magnitude of the effect diminished in the ASD group as compared to the NT group. Interestingly, quasi-experts reported a higher proportion of “likes” for rectilinear as compared to curvi- linear designs. These findings are discussed in relation to the role played by individual differences, including expertise, and the impact of specific dimen- sions of the stimuli in determining participants’ preferences.