To explain how moving in synchrony produces this effect, Tarr likes to demonstrate a psychological trick called the rubber hand illusion. Imagine sitting at a table and resting both of your arms on the tabletop. An experimenter conceals your right arm and replaces it with a rubber arm. When you look down, you see your own left arm and the fake rubber arm where your right arm should be. The experimenter then strokes the rubber arm with a paintbrush, which you can see, while simultaneously stroking your real right arm out of view, which you can feel. Your brain simultaneously receives these two
...more
