Phantom limbs are a striking demonstration of the importance of the body for self-consciousness.
Women may experience phantom breasts after mastectomy; men can experience phantom erections after amputation of a cancerous penis; and there are reports of phantom eyes, noses, teeth, and even phantom haemorrhoids, bowel movements and gas after surgical removal of the rectum.
Phantom sensations occur because the brain creates a dynamic model of the body by integrating tactile and visual information with limb position signals from the muscles and tendons. This model, variously called the “body schema” or “body image”, is crucial for both the perception and control of the body. But when a limb or other body part is removed, the schema is not properly updated, and so it retains an imprint of the missing part. As a result, the individual remains conscious of the missing part – often, even more so than of their existing body parts.
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Research into bodily awareness is leading us to rethink the nature of consciousness. Our understanding of how the brain works will progress only when we stop observing the brain in isolation, and start thinking of it as one part of a system that includes the body and its environment.















