Abstract
Ernst et al (2000, Nature Neuroscience) reported that haptic feedback increases the weight of a consistent surface-slant signal relative to inconsistent signals. In their experiment, the visual and haptic slants are static during both the training (learning) and the test (measurement) phases. In this study, we investigated the effects of dynamic haptic learning on the weights of disparity and perspective for the dynamic and static slant perception to explore the extent of the effect of the haptic learning among the stimuli with different aspects of temporal property. In the haptic learning phase, the subjects rotated the real circular paddle with both hands actively and viewed a virtual surface at the corresponding position of the real paddle through a mirror stereoscope. One of the visual depth cues for the perception of surface slant, disparity or perspective, was changing to synchronize with the rotation of the real paddle to present the consistent information with the haptic slant. In the test phase, the visual circle rotating (dynamic stimulus) or slanted (static stimulus) about the vertical axis was presented using the stereoscope. It had the depth cues of disparity and perspective, which indicated different angles. The subjects responded the perceived slants for the stimuli with various combinations of disparity and perspective cues to measure the weights between them for perceiving a slant. The test phases were performed before and after the haptic learning phase and the weights measured in the phases are compared. The results showed that the clear differences of weights before and after the haptic learning were not observed for both dynamic and static conditions.