What do Skeffington’s Circles, depth perception and the shape of the sky have in common? I can give you a brief overview of these ideas but to really understand how they are related, you must come to the VDR Symposium at COVD’s annual meeting!
Skeffington’s model of vision is represented by these 4 intersecting circles, with vision emerging from the intersection of all four.
- Anti-gravity: the total motor system of the organism that is used by it for exploration, locomotion and organization of itself within the environment.
- Centering: provides the awareness of me-it relationships that come from movement through space.
- Indentification: the performance area that provides “whatness” to the objects within the environment.
- Speech/Auditory: permits and provides communication skills completely unique to humans.
Although all 4 circles are involved in everything we do all day long, it is useful to consider them in isolation when working with patients, in both diagnostic and therapeutic modes. In the words of Dr. Harold Solan, how you conceptualize the problem will determine your approach to treatment. For purposes of this discussion, I would like to consider the anti-gravity and centering circles.
As we develop the ability to move through space, we gain the ability to interact with and manipulate objects in our environment. One result of growth and development within the anti-gravity circle is a much better of sense of self; of “where am I” in this environment. Through many experiences of this type there is refinement and the development of localization; where is it? Centering develops as the attentional and orienting process that involves selecting an object for attention and directing the body, head and eyes toward it.
Binocular vision and depth perception are dependent upon visual development within these 2 circles. In order to accurately point both your eyes at an object, you must understand where you are and the distance between you and that object. The development of these processes is multi-directional. Not only are there interactions between all 4 circles, but experiencing depth perception will create feedback that enhances localization, centering, movement and language.
But what if you are strabismic? The strabismic patient does not perceive the world the same way, when the eye is turned. This very often causes them to “suffer” from poor depth perception, or at least less robust depth perception. But often, if there is a point in space where the eyes are aligned, they will appreciate depth. And if their appreciation of depth can be enhanced, improvements in all the other aspects of vision will follow, including learning to keep their eyes aligned.
In the recently published article, The shape of the sky: the art of using egocentric stereopsis in the treatment of strabismus, Dr. David Cook dives into Skeffington’s circles as part of an approach to the treatment of strabismus. By helping these patients increase their awareness of the entirety of visual space, they can develop a better understanding of their relationship to objects, and their appreciation of depth. This in turn will encourage patients to increase the accuracy of their ability to locate objects in space which will increase the accuracy of their eye alignment. He discusses the use of the most modern technologies while acknowledging the work of pioneers in the treatment of strabismus, beginning over 100 years ago .
As patients progress through their therapy program, Dr. Cook suggests taking them for a walk to observe and appreciate a 3 dimensional world and the shape of the sky. After all, why pursue the “gift of binocular vision” if not to help your strabismic patients be instantly aware of an object’s identity and position in space and to answer the questions, “what is it,” and “where is it?”
**The VDR Symposium is happening at 7 pm on Wednesday April 26th. The symposium will focus on 2 unique publications from COVD’s journal, Vision Development and Rehabilitation. Dr. Cook will be joined by Dr. Samantha Slotnick during a roundtable discussion of The Shape of the Sky. The symposium will also focus on Sports Vision and Major League Baseball, with Drs. Robert Byne and Noah Tannen. **
(featured photo by Jack Delano, 1942, Flagman standing at a distance behind a Santa Fe R.R. west bound freight train during a stop, Bagdad, Calif. Courtesy of the Library of Congress via Flickr)