What to do?
1.Make a copy of the pattern disc provided and cut out the pattern. Using glue, mount the disc on a circle of cupboard and attach the centre of the disc to a rotator
2.Start the spiral rotating and concentrate at the centre of the disc for about 15 seconds.
3.After 15 seconds, look away from the disc and stare at nearby person or a wall. Now you can feel that the person or the wall on which you are staring at seems to be expending or contracting like he or she is rushing towards you or away from you.
4.You can try rotating the disc in the opposite direction also if it’s possible. After that, when you look up from the spinning pattern, see yourselves what happens.
This is because of the fact that our visual system is sensitive to inward and outward motion. There are two types of nerve cells in us, one sending more impulses when objects move outward from the centre of our field of view and others that send impulses more while objects move inwards. These two types of nerve cells will send impulses equally when we look at something that stands still. This will balance the impulses. But only one set of nerve cells will work when we look a moving pattern. And also they will get tired soon and we feel a kind of giddiness. Now, when we look away from the rotating pattern, the other set of nerve cells begin to work more. This will give us an impression that the object we are starring at is either moving in or out.
So if we are looking at a spiral pattern that seems to be moving away from us, look up towards a wall. We will feel the wall seem to be moving towards us. If we rotate the spiral in the opposite direction, it will make us feel moving towards us and the wall will seem to be moving away when we look up.