Abstract
In humans, vision is the most accurate sensory modality for constructing our representation of space. It has been shown that visual impairment negatively influences daily living and quality of life. For example, spatial and locomotor skills are reduced in this population. One possibility is that these deficiencies arise from a distorted representation of the body. Body representation is fundamental for motor control, because we rely on our bodies as a metric guide for our actions. While body representation is a by-product of multisensory integration, it has been proposed that vision is necessary to construct an accurate representation of the body. In the MySpace project, we are investigating the role of visual experience on haptic body representations in sighted and visually impaired (VI) participants. To this end, we employ a variety of techniques to investigate two key aspects of body representation 1) size perception, and 2)the plasticity of the proprioceptive system. These techniques include landmark localization, psychophysics, and the rubber hand illusion. Our results in sighted participants show distortions in haptic but not visual body representation. In the VI participants there are distortions when estimating forearm, hand, and foot size in several different haptic tasks. Moreover, VI children fail to update their perceived body location in the rubber hand illusion task. Collectively, our findings support the hypothesis that vision is necessary to reduce distortions in haptic body representations. Moreover, we propose, that VI children may develop with impaired representations of their own bodies. We discuss possible opportunities for reducing this impairment.