Purpose:  To teach ability to visualize large areas of space per given unit of time.

Materials:  100 Watt light source placed six to eight feet from observer.


1.  Dim the room.  Patient is to sit with eyes closed for one minute; open eyes.

2.  Turn on light and have patient look at it for count of 10.

3.  Now he is to close eyes, but continue to look at place where light was located until no further afterimage is seen.  Be aware of any objects seen around the afterimage of the light source.

4.  He should be aware of the rest of the space around him as blackness.

5.  Then repeat the process.  Do this for no more than 10 minutes.

Aspects to be emphasized:

1.  Sees white blob.

2.  Sees flowering colors.

3.  Target size to image size ratio (same, larger, or smaller).

4.  Where does blackness begin (at face, a foot in front of patient, or where?)

5.  Volume of blackness (a few feet, size of room, or whole out-of-doors)

6.  Sees objects located around light source in the afterimage.