Purpose: To develop awareness of the binocular visual fields
Apparatus: A special paper mask with two diamonds cut in it will be provided. One diamond has a blue line at each vertical point, and the other diamond has a red line at each horizontal point
Method:
Patient is instructed:
1. While standing, hold the mask in front of your eyes and look at an object across the room through the diamonds.
2. Try to see one large diamond in front of your face with the blue and red lines in their proper place.
3. Move the mask away from your face slowly toward the object.
4. When the mask is about six inches from your eyes, stop.
5. Keep looking through the diamonds. How many do you see?
6. If you see three diamonds, look through the middle one at the target across the room. The right and left holes are like an extra set. Try to keep the middle diamond its true shape (without distortion), and the red and blue lines in their proper place.
7. Keeping looking through the middle diamond and try to see the object across the room as single. Try to see the edge of the middle diamond and the cross around it as clearly as you can.
8. Slowly extend your arms until the mask is held at arm’s length, and then back again to six inches. Practice this until you can do this without losing clarity through the middle diamond or the cross around it.
9. Next, while holding the mask about 13 inches from your eyes, turn your body slowly to the right and to the left. Keep your feet in place and keep looking through the middle diamond as your move. Move slowly. Can you keep seeing the three diamonds?
10. Now, hold the mask at 13 inches again. While looking through the middle diamond, move the mask in a circle. Keep your body facing straight ahead. Rotate the mask in small circles, clockwise and counterclockwise. Move only your arms and your eyes. Can you continue to see the middle diamond clearly?
Aspects to be Emphasized:
1. Ability to maintain awareness of three diamond holes in true shape.
2. Ability to see clearly through the diamond and maintain awareness and alignment of the red and blue lines.
3. Ability to maintain #1 and #2 under varying conditions:
-moving mask closer and further
-rotating your body
-rotating the mask
