Your brain is an incredibly powerful organ, but it's still pretty easy to trick. Take a look at the image above- some of the circles will look like they’re spinning because of an optical illusion called a peripheral drift illusion. Here are a few "brain hacks" that you can try out for yourself to see just how easy it is to deceive your brain.
The Ganzfield Effect
How about a trippy experience without the aid of illegal substances? Research carried out back in the 1930s by a psychologist called Wolfgang Metzger found that sensory deprivation can induce hallucinations. It’s easy to do yourself at home, and all you need is an mp3 player, headphones, a ping-pong ball and a red light.
Download white noise onto your mp3 player and cut the ping pong ball in half. Turn the red light on, then put your headphones in and play the white noise. Then tape the ping pong balls to your eyes. Try to make sure light isn’t leaking through the sides. Sit back and relax, and wait for the images to come to you. This should induce some fairly bizarre hallucinations.
Optical Illusions
Check out this silhouette of a dancer. Is she spinning clockwise or counter-clockwise? For me, she’s spinning clockwise, but after a few seconds of staring around the image she appeared to change direction. But of course, she isn’t really spinning in one direction at all, and she doesn’t change direction. Although this is a 2D image, our brain assumes it is 3D and thus tries to interpret it as such. If you focus on something around the girl, maybe the background or the shadow, your brain may reconstruct the image and decide that it is spinning in the opposite direction.
Image credit: Nobuyuki Kayahara, via Wikimedia Commons.
Phantom Sensations
Phantom sensations refer to experiences from limbs that are not part of your body. You can also do this at home, but you need a volunteer, and a fake hand.
Cover your hand with a box on a table so that you can’t see it, and place a fake hand next to it. Get your buddy to start stroking both your hand and the rubber hand in the same place at the same time for a few minutes. After a short time, you should start to feel as though the rubber hand is your own. If you’d like to take it a bit further, you can get your friend to violently strike the rubber hand which should induce pain because your brain has been deceived into thinking it is your hand.
Purkinje Lights
Physiologist Jan Purkinje once stumbled upon a pretty cool hallucination which is very easy to induce. All you need to do is close your eyes and tilt your head towards the sun. Wave your hand back and forth rapidly in front of your closed eyes for a few minutes, and you should eventually start to see some images which will gradually become more vivid. This happens because the stimulation causes cells within the visual cortex to fire in unpredictable bursts.
Shrinking Pain
Back in 2008, a team of researchers from the University of Oxford made an intriguing discovery; binoculars can be used to reduce pain.
Participants with chronic pain in an arm were asked to look at their hand and perform certain movements under different conditions; no visual manipulation, looking through binoculars that didn’t do anything, looking through functional binoculars that increased the size of the hand, and looking through inverted binoculars that decreased the size of the hand. Remarkably, they found that the inverted binoculars reduced the pain felt in the hand, and even reduced swelling. They also found that magnifying the hand through normal binoculars increased the pain. They think that this is because pain responses can be influenced by the perception of danger, i.e. the worse it looks, the more your brain does to protect it.
