Incorporating the fact that the senses are embodied is necessary for an organism to interpret sensory information. Before a unified perception of the world can be formed, sensory signals must be processed with reference to body representation. The various attributes of the body such as shape, proportion, posture, and movement can be both derived from the various sensory systems and can affect perception of the world (including the body itself). In this review we examine the relationships between sensory and motor information, body representations, and perceptions of the world and the body. We provide several examples of how the body affects perception (including but not limited to body perception). First we show that body orientation effects visual distance perception and object orientation. Also, visual-auditory crossmodal-correspondences depend on the orientation of the body: audio “high” frequencies correspond to a visual “up” defined by both gravity and body coordinates. Next, we show that perceived locations of touch is affected by the orientation of the head and eyes on the body, suggesting a visual component to coding body locations. Additionally, the reference-frame used for coding touch locations seems to depend on whether gaze is static or moved relative to the body during the tactile task. The perceived attributes of the body such as body size, affect tactile perception even at the level of detection thresholds and two-point discrimination. Next, long-range tactile masking provides clues to the posture of the body in a canonical body schema. Finally, ownership of seen body parts depends on the orientation and perspective of the body part in view. Together, all of these findings demonstrate how sensory and motor information, body representations, and perceptions (of the body and the world) are interdependent.

Going into space is a disorienting experience. Many studies have looked at sensory functioning in space but the multisensory basis of orientation has not been systematically investigated. Here, we assess how prolonged exposure to microgravity affects the relative weighting of visual, gravity, and idiotropic cues to perceived orientation. We separated visual, body, and gravity (when present) cues to perceived orientation before, during, and after long-term exposure to microgravity during the missions of seven astronauts on the International Space Station (mean duration 168 days) and measuring perceived vertical using the subjective visual vertical and the perceptual upright. The relative influence of each cue and the variance of their judgments were measured. Fourteen ground-based control participants performed comparable measurements over a similar period. The variance of astronauts’ subjective visual vertical judgments in the absence of visual cues was significantly larger immediately upon return to earth than before flight. Astronauts’ perceptual upright demonstrated a reduced reliance on visual cues upon arrival on orbit that re-appeared long after returning to earth. For earth-bound controls, the contributions of body, gravity, and vision remained constant throughout the year-long testing period. This is the first multisensory study of orientation behavior in space and the first demonstration of long-term perceptual changes that persist after returning to earth. Astronauts showed a plasticity in the weighting of perceptual cues to orientation that could form the basis for future countermeasures.