The Rubber Hand Illusion

Credit: 'The Ego Tunnel: the science of the mind and the myth of the self' by Thomas Metzinger

Credit: 'The Ego Tunnel: the science of the mind and the myth of the self' by Thomas Metzinger

The Rubber Hand Illusion is a pretty cool trick, but it also gives us an interesting insight into the relationship between our brains and our bodies.

In a simple experiment, psychologists found that they could convince people that a rubber hand was their own by putting it on a table in front of them, hiding their real hand, and then stroking it in the same way as their real hand.

By mixing up the signals from two different senses – sight and touch - we can trick our minds to believe that the fake hand is our own. This is so extreme that after a few minutes of stimulation we expect to be able to feel pain in the fake hand and move it at will.

In the BBC Horizon video below people even flinch when the psychologist running the experiment takes a hammer to the fake hand! Even though the hand is clearly a dummy, their brain is ‘tricked’.

Interestingly, when participants are asked to explain where on the table their real hand is, on average they believe their real hand to be closer to the fake hand than it actually is.

Even more amazingly, when participants in the study who confused the fake hand for their own, their own hidden hand became on average half a degree colder.

So what does this tell us about the link between our brains and our bodies?

Well, it tells us that our brains respond to external stimuli when regulating the autonomic nervous system. This is the part of the nervous system which controls things like heart rate, digestion, respiratory rate and the fight-or-flight response.

We find this interesting because as a company we work on projects that use technology to naturally change how you feel, think and behave.

doppel does exactly this - your body responds to an external stimulus (in this case doppel’s heartbeat) and you feel calm and focused.

Read more: How doppel works

So for us the Rubber Hand Illusion is more than an amusing trick to test out with your friends, it’s a window into the world of psychophysiology.