- Go into a room, shut the door and turn out the lights so that the room is mostly dark.
- Wait until your eyes adapt to the darkness. You should be able to make out the basic shapes of the room from the tiny bit of light coming in from under the door.
- Next, close your right eye and cover it with your hand. Turn the light on, keeping your eye closed and covered. Leave the light on for about a minute or until your left eye has adapted to the light.
- Uncover your eye and look around the darkened room.
This illusion was discovered by Uta Wolfe and he says it is somatosensory illusions. He also says it is similar to "phantom limb". He also says the visual response overrides the physical response. This was significant to explain because this is somewhat like what is happening in the illusion. We do not normally see our eyelid, we only know it is closed because the area is darkened. This illusion works because only one eye in adjusted to the dark, which makes it feel as though the eyelid is closed during the time it takes for it to adjust to the room.