The contribution of stimulus attributes of three-dimensional solid forms and level of discrimination to the visual and haptic percept of balance.

Design-trained subjects sorted fourteen solid forms under either visual or haptic conditions into groups on the basis of perceived similarity of balance or along a balance continuum. After these tasks of coarse and fine discrimination, each form was rated on ten bipolar stimulus attributes. Multidimensional scaling and property-fitting analyses were performed on the results of four experiments to determine the combined contribution of stimulus attributes and level of discrimination on the visual and haptic percept of balance. A balance dimension emerged for both modalities, but only when subjects were inclined to attend globally to the structure of a form by the coarse-discrimination task. Results indicate that visual balance is a holistic property of forms which derives from the synthesis of physical stimulus information. For touch, subjects appear to have equated balance with a symmetric distribution of weight/shape about the central axis of a form. Findings are related to theoretical notions of balance.