Visual Features Involved in Determining Apparent Elasticity Elicit Touch Desire

Elastic materials often invite the direct touch of users. It is an open question how seeing elastic materials invokes touch desire. The present study proposes a novel visual feature that modulates apparent elasticity and touch desire. The stimulus for our experiment was a clip in which a computer-rendered elastic surface was indented by a needle-like bar. The features of this stimulus that we focused on were spatial deformation range and indentation depth. Observers rated the following three impressions: apparent elasticity, touch desire, and anticipated touch pleasantness. The results showed that both apparent elasticity and touch desire peaked in the middle of the spatial deformation range. The two impressions also depended on indentation depth and were highly correlated with each other. Anticipated touch pleasantness showed a different peak tendency than the other two. An additional block showed that the deformation realism was not related to the above three impressions. The results suggest that apparent elasticity eliciting touch desire can be determined in the parameter space defined by the spatial deformation range and the indentation depth.