[How do] humans’ wealth of sensory inputs—including the touch and visual perception involved in manipulating a tool—modify the sense of one’s physical self? Embodiment implies that when one holds a screwdriver, for example, the brain morphs its representation of a “hand” until that representation reaches all the way to the very tip of the tool.
But is this what really happens? Why should the brain somehow give up, even temporarily, its conception of a dexterous hand for that of a blunt instrument?
[Neuroscientist Tamar Makin] examined whether people with prostheses—or London street cleaners wielding litter-grabbing metal poles—do, in fact, merge their identities with such tools. So far the results of Makin’s studies contradict… some modern research that had suggested using an implement alters internalized body maps.
“Embodiment is a multifaceted phenomenon. If you ask the brain, or at least the visual cortex, of the people who use the prosthesis more, their organs embody the prosthesis less. But if you ask people about their subjective experience of how they perceive the prosthesis after long periods of use, the more they use it, the more they say it feels like part of their body,” [Makin said.]