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The eyes appear to move and follow you as you walk around the room.

Are you looking for a way to make your drawings look alive? Try this activity and make an awesome creepy face whose eyes follow you as you move around the room.

By Mike McRae

You will need

• Paper
• Pencils and felt pens
• Scissors
• Sticky tape

What to do

1. Draw a face onto the paper. We found that an animal face works well. Give your face circular eyes that are about three centimetres across. Make the whole face around fifteen centimetres wide. Colour and decorate it as you like.
2. Cut two slits at the very sides of the face at the same level as the eyes. The slits should run up and down, and they should be about five centimetres long. Younger readers may need an adult to help cut the slits.
3. Cut out the eyeholes. Afterwards, redraw the line around the outside of the eye – it’ll make the illusion work much better.
4. Cut out a strip of paper five centimetres wide and 20 centimetres long.
5. Place this strip through the slits, so the strip goes behind the mask. Bend it slightly so there is about one centimetre between the mask and the eye strip, and then tape the strip in place.
6. Draw two pupils on this strip so they can be seen through the eyeholes.
7. Hold the mask at eye height or tape it to the wall and move about. The eyes should follow you as you walk around the room, so it looks as though the mask is watching you wherever you are!

What’s happening?

The eyes appear to move and follow you as you walk around the room, but it is actually an optical illusion. Optical illusions play with the way you see and understand the world.

This optical illusion happens because the drawn eyes and face are not on the same piece of paper. The eye holes frame the pupils, but secretly, there is distance between them. Our brains interpret this as the pupils moving to follow us around the room.

We don’t think too much about seeing the world. We don’t usually notice our eyes moving and looking around and we don’t notice how our brain interprets what we see. There are, however, many interesting things happening in our eyes, in the way they move and in what happens between our eyes and our brain.

We see when light enters our eye through the pupil and passes through a lens. This lens can change shape to makes sure that the light lands on the retina at the back of our eye.

Information is sent to our brain through electrical impulses from cells in the retina. Our brain then turns these electrical impulses into information about what’s around us.

Real-life science

Eye movement studies have found that we only look at certain elements of a whole picture, and we keep coming back to those same elements, especially if they are unusual or different.

Scientists can measure eye movement a couple of ways. They can use a contact lens-like attachment that fits onto the eye directly, they can film the eye with a camera, or they can attach electrodes around the eye to measure eye movement.

When looking at websites, researchers have found we move our eyes in an F shape. We first scan across the top of the website and then move down a little and look across again. We then scan down the side of the page. This means if you want to be sure visitors to your webpage read some particular information, you should include it in the top paragraph. (This gets us thinking that if you are still reading this paragraph you are defying what’s normal! Good work!)

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