Abstract
It has long been known that motion facilitates the visual perception of 3-D object shape, particularly when surface texture or other trackable object features are present (e.g., Wallach & O’Connell, 1953; Braunstein, 1966; Todd et al., 1985; Norman, Lee, Phillips, et al, 2009). Conventional models of structure-from-motion require the presence of texture or trackable object features in order to recover 3-D structure. Is the facilitation in 3-D shape perception similar in magnitude when surface texture is absent? On any given trial in the current experiment, 30 observers were presented with a single randomly-selected bell pepper (for 12 seconds) and were required to indicate which of 12 simultaneously visible bell peppers possessed the same shape. The initial single pepper’s shape was defined either by boundary contours alone (i.e., presented as a silhouette), specular highlights alone, specular highlights and boundary contours, or volumetric texture. In addition, there was a haptic condition: in this condition, the observers felt (but could not see) the initial single object for 12 seconds. For both the visual and haptic conditions, motion (rotation in depth or active object manipulation) was present in half of the trials and was not present for the remaining trials. A 2x5 split plot ANOVA demonstrated that the effect of motion was quantitatively similar for all of the visual and haptic conditions (F(1, 25) = 70.8, p <.000001) -- the observers’ performance was 93.5 percent higher in the motion or active haptic manipulation conditions (when compared to the static conditions). The current results demonstrate that deforming specular highlights or boundary contours facilitates 3-D shape perception as much as the motion of objects defined by surface texture. The current results also indicate that the improvement with motion that occurs for haptics is similar in magnitude to that which occurs for vision.
Meeting abstract presented at VSS 2013