The Aliasing of Images:
A Neurophysiological Basis for Some Reading Problems
Merrill D. Bowan, O.D. Neurodevelopmental Optometrist APPARENT, ILLUSORY MOVEMENT The figure at the right is called the Enigma Painting because of the apparent movement in the rays/arms. Where is the movement in this illusion occurring? The answer is, in your brain, of course. Now, close one eye. The illusions will reduce for most observers. Switch eyes. Did the quality of the movement change? Remember this - keep this in mind.
On the left is another variation of the illusion.
Do you see the counter-directional race going on in the tracks? It seems to me that when I look at a track and move my eyes clockwise in a short bit, the movement goes clockwise. And when I do the opposite, the movement goes counter-clockwise. Anyone else note this now? At the right is the same pattern, but the scientist wanted to determine if it was the rings or the rays that contributed the “active ingredient” to the illusion. So, he isolated the rings. Note that there is no movement. It is the striping of the rays - the grating that the rings are set in - that makes the movement occur. Have you ever heard a patient complain that the print moves on a page? Similar to the illustration in FIG. 4 below. This is an illustration of a child’s description of the “River” motion – taken from Rhonda Stone’s book “The Light Barrier” – with words rippling as though water was running down the page. Or, perhaps there will be shimmering, a swirling movement like in FIG. 5. This is the swirling pattern. Please note that this illustration is take from Helen Irlen’s book, “Reading by the Colors”. The fixation point is clear, but the peripheral text is swirling and smeared in appearance.
The Aliasing of Images: a Neurophysiological Basis for Some Reading Problems
Page 2 Irlen has had mixed success using colored filters to stabilize the image for certain sensitive individuals for short to long-term periods. Solan did...