To prove that what we see is often affected by what we expect to see with the help of the mirror image experiment.
1. Mirrors - 2 in number, square in shape, 12 inches (30 cm) a side, could be either made out of plastic or glass.
2. Epoxy glue and duct tapes.
3. Wooden dowels - 2 in number with diameter as 1 inch (2.5 cm) and 12 inches (30 cm) long.
1. Stick the mirrors together by pasting their backs. If you have a glass mirror then for safety, tape their edges using the duct tapes to seal the sharp edges. Take the two wooden dowels and paste them right in the centre of the mirrors vertically.
2. Hold the dowels with each hand and as you look at one side of the mirror move the hand which is on the other side. What do you actually see?
Your brain expects the image in the mirror to move as it is fooled to believe that the image it sees is actually your other hand. Thus when you move your other hand the nerves tells the brain that the hand is moving while the image which it sees doesn't actually move.
Our brain is tricked into thinking that the image should move according to the hand and hence the conflict arises which it doesn't enjoy.