Severe pain/pain-related fear prevent improvement of motor function, hence rehabilitation for pain is one of most important matter in clinical practice. Recent studies revealed that pain perception was modulated with multi-modality (e.g. visual information, auditory information). Seeing own body which projected on the mirror or virtual space reportedly attenuate pain perception, such attenuate effect was called “Visually induced analgesia”. Additionally, seeing size/color manipulated own body reportedly attenuated pain perception much further. However, we reported seeing rubber hand which appearance was manipulated to elicit participants negative emotion. We conducted such rubber hand illusion paradigm using “injured rubber hand” to evoke unpleasantness associated with pain, a “hairy rubber hand” to evoke unpleasantness associated with embarrassment, and a “twisted rubber hand” to evoke unpleasantness associated with deviation from the concept of normality. The pain threshold was lower under the “injured rubber hand” condition than with the other condition. Such modulation of pain perception could not be adequately interpreted as cross-modal shaping pain. Therefore, we thought again about “cross-modal shaping pain” in the perspective from projection science, hence then proposed new pain rehabilitation model in the review article. We particularly focused on the process of back-projection which has potential to improve pain-related negative emotion and distorted body image. The proposed rehabilitation model would be an opportunity for future interdisciplinary approaches.
