Evidence for ‘Visual Enhancement of Touch’ Mediated by Visual Displays and Its Relationship with Body Ownership

Several studies have shown that watching one’s own body part improves tactile acuity and discrimination abilities for stimuli presented on that location. In our experiment we asked the participants to localize tactile stimuli presented on the left or right arm. During the task the participants were not allowed to watch their body, but they could see another person’s left arm via a LCD display. This arm could be touched or not during the presentation of the tactile stimuli. We found that when the participants saw a finger touching the arm on the screen, their responses to the tactile stimuli presented on the left and on the right arm were faster than when the arm on the screen was approached but not touched. Critically, we did not find any illusion of ownership related to the hand seen on the screen. We concluded that the effects found might be mediated by higher order multisensory mechanisms related to the allocation of attentional resources to the body.