We studied whether vision can teach touch to the same extent as touch seems to teach vision. In a 2 x 2 between-participants learning study, we artificially correlated visual gloss cues with haptic compliance cues. In two "natural" tasks, we tested whether visual gloss estimations have an influence on haptic estimations of softness and vice versa. In two "new" tasks, in which participants were either asked to haptically judge glossiness or to visually judge softness, we investigated how perceptual estimates transfer from one sense to the other. Our results showed that vision does not teach touch as efficient as touch seems to teach vision. Wismeijer, D. A., Gegenfurtner, K. R., & Drewing, K. (2012). Learning from vision-to-touch is different than learning from touch-to-vision. Frontiers in integrative neuroscience, 6, 105.
The active control of exploratory movements is an integral part of active touch. We investigated and manipulated the relationship between the haptic discrimination performance for small bumps and the direction of exploratory movements relative to the body. Shape discrimination performance varied with the direction of stimulus exploration. Experimental manipulations successfully changed the normative relation between exploratory direction and discrimination performance. If participants were rewarded for “good perceptual performance” and had the choice, they displayed clear strategic preferences for exploratory directions that yield optimal performance—but only after having extensive experience with the changed perceptual conditions. Overall, the findings suggest that participants can actively adapt their exploratory movements in order to optimize haptic discrimination performance. Drewing, K. (2012). After experience with the task humans actively optimize shape discrimination in touch by utilizing effects of exploratory movement direction. Acta psychologica, 141(3), 295-303.
