The Rubber Hand Illusion and Phantom Limb Pain

 Some people are born with a missing limb as a product of a genetic marker, or a deformity. Others need a limb amputated due to physical injury, cancer, infections, etc. A common occurrence that happens to most people after their limb is amputated is called phantom limb pain. This is when someone still feels the pain that a limb would feel. For example, after getting your left leg amputated, you run into a corner of a table, and feel a painful sensation that happens after stubbing your toe, except your foot is not there anymore.

To conduct research on this phenomenon, the rubber hand illusion has allowed researchers to collect and gather information on phantom limb pain. To conduct this, your forearms are facing down on the table, are separated by a wooden block, so you are unable to see what is happening to the left arm. A rubber hand is then put in place of your left hand with identical positioning to your right hand. 

The researcher then strokes both hands with a small paintbrush, giving a sensation to your nerves, allowing you to feel the stroking motion of the brush. After a couple minutes of this, you begin to feel the rubber hand as your own. Your body then would respond as if the rubber hand was your own as well. To test this, the researcher may grab the index finger of the rubber hand and bend it so far backwards that if it was your real hand, the finger would break. Most subjects feel this pain on the rubber hand as their own. 

After reading this chapter of the book, I went on YouTube to watch videos on how this test worked. Here is a link below to video I watched. 

Link:

https://www.youtube.com/watch?v=DphlhmtGRqI