The Rubber-Hand Illusion Will Blow Your Mind
This is how and why a rubber hand can feel like your own
The brain is the most complex organ in the world.
It is the place where everything happens, from our perceptions and emotions to consciousness. But things don’t stop there because how you feel your viscera and limbs is also a perception of your brain.
And yup, it is quite easy to fool!
Let me show you how people can believe a rubber hand is their natural hand.
How To Make People Believe A Rubber Hand Is Its Real One?
The rubber hand illusion is a perceptual trick manipulating our brain’s sense of body ownership.
The only things you need for this experiment are:
A participant
A “scientist”
A rubber hand
Something to hide the real hand
First, a participant’s natural hand is hidden from view, while a rubber hand is placed in front of them (like the image below). Second, the “scientist” starts touching both hands with synchronized touches. Slowly, the brain begins to perceive the rubber hand as part of the body, with the participant feeling the sensations of touch in its artificial limb.
To make it more real, the “scientist” can use other tools like a paintbrush.
Third and finally, after some minutes of touching the hand with different tools, the “scientist” takes a hammer and quickly HITS the rubber hand.
Boom!
Participants freak out.
Why? Because the sensation was so real, they could feel the pain of the hammer hit. This is because the brain started believing the artificial limb (the rubber hand) was the real one.
Check this video for a real-time demonstration.
Believe me, it is worth the time.
How Does This Happen?
This fantastic illusion shows us how something so natural, like limb perception, can be easily fooled. Although it is still debated how exactly this illusion works, scientists generally understand it.
The rubber hand illusion happens because of how our brain works.
Our brain relies on a mix of sensory inputs, such as vision, touch, hearing, viscera, etc., to create a nice representation of our surroundings and body. The perception of your viscera is called interoception, and it is one of the reasons for how and why you perceive yourself as you.
For example, you only consciously feel your stomach when it's in pain.
That’s interoception. So when sensory signals from the rubber hand and the natural hand are synchronized, the brain integrates all these inputs, making it believe that the rubber hand is part of us.
Our human brains prioritize visual information and override conflicting sensory signals to maintain a consistent perception of the body.
And that’s why a rubber hand can feel like your own :)
Variations Of This Illusion Can Be Used For Some Clinical Interventions And To Understand Consciousness
Although this is a funny experiment, it has implications that extend to our everyday lives.
By studying the perception of body ownership, scientists can understand the complexities of human perceptions and how their illusions shed light on how our brains work. Plus, some variations of the rubber hand illusions can be used for different clinical interventions in conditions such as chronic pain and body image disorders.
For example, some people have issues perceiving limbs that are no longer there, a phenomenon called phantom limb. These variations of the illusion can help people suffering from these problems.
Basic science, like this illusion, can make a big impact on people’s lives.
That’s why knowledge should always be a priority :)
The brain is fascinating.
It’s the origin of everything we experience—our emotions, perceptions, consciousness, and behaviors. Every thought and action is driven by complex biological algorithms that evolved over millennia, shaping our nervous systems into finely tuned machines.
Ultimately, our brains are what make us human.
The more we understand it, the closer we understand ourselves and other life beings.
Until the next time,
Axel