Two dimensional shapes for emotional interfaces: Assessing the influence of angles, curvature, symmetry and movement

Recent investigations aiming to identify which are the most influential parameters of graphical representations on human emotion have presented mixed results. In this study, we manipulated four emotionally relevant geometric and kinematic characteristics of non symbolic bidimensional shapes and animations, and evaluated their specific influence in the affective state of human observers. The controlled modification of basic geometric and cinematic features of such shapes (i.e., angles, curvature, symmetry and motion) led to the generation of a variety of forms and animations that elicited significantly different self-reported affective states in the axes of valence and arousal. Curved shapes evoked more positive and less arousing emotional states than edgy shapes, while figures translating slowly were perceived as less arousing and more positive than those translating fast. In addition, we found significant interactions between angles and curvature factors both in the valence and the arousal scales. Our results constitute a direct proof of the efficacy of abstract, non-symbolic shapes and animations to evoke emotion in a parameterized way, and can be generalized for the development of real-time, emotionally aware user interfaces.