Time and Direction

Dr. William Lee was the 2nd recipient of the Skeffington Award, in 1972.  In his book, Each Of Us An Island, he describes “those systems which form the building blocks of the manner in which man performs.”  I have chosen to to focus on his chapter on time and direction.  Time and direction are the building blocks of all perceptions, not just visual perception.

Our sensory systems measure energy, such as sound waves, pressure, gravity, or, in the case of the visual system, light.  In addition to intensity, these measurements include discernment of time and direction: the length of time the stimulus is present and the direction in which the stimulus is traveling when the measurement is made.  All the sensory systems can measure time, but the visual system is the most accurate system for measuring both time and direction.  Think of a blind person trying to navigate in an unfamiliar environment.  They may depend upon a sighted individual or guide dog to help them obtain accurate directional information.

Time and direction are an integral part of perception.  Without direction, there is no beginning or end, only on or off.  Motion or movement is the combination of time and direction.  Understanding movement (either of oneself or other objects) requires the visual processing of time and direction.  Without an ability to use vision to make judgements about time and direction, the individual will have difficulty performing activities that require movement. Imagine that you have an appointment that requires you to be at a certain location at a certain time.  In order to get there, you have to know where you are starting from.  If you do not know where you are, it is impossible to know in what direction to proceed or how long it will take to get there.  Now imagine that you are playing baseball.  How will you know when to swing the bat if you do not know the direction from which the ball is coming and the speed at which it is traveling?  Finally, imagine you are a second grader trying to read a book.  In order to read efficiently, you must make make small eye movements called saccades moving from left to right.  If you cannot coordinate the timing and direction of the saccades, reading becomes very difficult.

Since time is infinite, stretching from the past, throughout the present and into the future, processing time requires breaking this timeline into intervals.  Let us look at a behavior, such as learning to write your name.  The first time you perform this activity, you have no basis for comparison.  The second time you perform this activity, you are able to compare your experience to past experience.  You can also anticipate what resources you will require to perform this again in the future.  Through these intervals of time, or cycles, we are able to learn.  If performance does not improve through these rhythmic intervals of time, then perhaps the individual does not possess the requisite skills.  The other possibility is that the individual is not able to use vision to accurately process time, and performs the right activity, but at the wrong time.  You turn right but at the wrong intersection; you swing the bat, but too late; you move your eyes to the next line of words, but you haven’t read the last few words on the first line.

Now consider performance of complex behaviors that require the coordination of several systems.  Think about the baseball player, but now he is in the outfield.  He sees the batter swing, he hears the sound of the ball hitting the bat, and he has to move in the right direction to catch the ball at the right time.  He has to coordinate all this information arriving at his sensory systems at different points in time and respond by accurately moving in the right direction through an accurately determined time interval.  Difficulties processing time and direction visually will make it impossible to perform this task successfully.  What if the outfielder is an 8th grader?  The information he is receiving is constantly changing due to his fast growth rate.  His past experiences are no longer reliable.  He has to constantly rebuild the coordination of all systems to perform successfully.

Visual processing of time and direction is essential to coordinated performance.  Many learning disabled children have difficulties in this area.  The result is often more accurately described as a “living disability” because these children have difficulty, not only in school, but at home and at play.  What can the developmental optometrist do to help the child who has difficulty with these skills?  Vision therapy will often include activities aimed at improving rhythm.  Providing an external clue to organize sensory inputs will support the motoric response or output.  These activities may involve the use of the metronome, music, flashing lights, hand clapping, swinging balls, and trampolines.  Activities can be done at home to enhance self-directed awareness of time intervals, such as skipping, jump rope, marching, or tapping the foot and clapping the hands to various patterns.  As the ability to process time improves, activities which require directional movement and the integration of the sensory systems can be incorporated into the therapy program.  Improving rhythm will improve the child’s ability to process time and direction.  The result is the ability to do the right thing, at the right time, in the right place.  Success.

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It Takes A Village

“It Takes a Village.”  That is the title of the book, written by Hillary Rodham Clinton in 1996, when she was the First Lady.  This title refers to an African proverb, “It takes a village to raise a child.” How appropriate to introduce this post from Dr. Leonard Press.  This post also appears on VisionHelp Blog.  Dr. Press has been building a strong village to support the needs of the children (and grown-ups) he serves.  He knows he can’t do it alone.  The more we interact with like-minded professionals, the more we will learn about how to help our patients.

I’ve had a fabulous time, twice over the past two weeks,  giving a day long seminar to occupational therapists, physical therapists and speech-language pathologists.  Our field has been blessed with colleagues who do a marvelous job of this, in particular Drs. Appelbaum, Hellerstein, Hillier and Scheiman.  Although I’ve been asked to put seminars like this together before, I’ve shied away due to time constraints.

Venturing first up the Hudson River along the Palisades Parkway to do the seminar in Spring Valley, and then down the New Jersey Turnpike for a gathering in Princeton, I had a blast.  One of the best things about having an interactive seminar with “the big three” therapies of OT, PT and Speech,  the ones who are part and parcel of early intervention services, is that they get it.  There’s no need to  convince any of the attendees of the importance of VT, only to work out a framework in which they can feel comfortable collaborating.

Here is what we covered:

seminar-visual-processing-and-therapy-oct-2010

I’m happy to share this information, though it isn’t as much the facts that makes the seminar special as it is the interaction.  In contrast with some professions who don’t grasp the science and substance of optometric vision therapy, those in attendance at these seminars grasped the concepts almost intuitively.  Ideas about the balance between structure and function, between reductionist disease models and holistic developmental models, and between the senses and the senseless resonated with each of the attendees.

My seminars are highly interactive, and though the PowerPoint slides in the hyperlink above will give you a feel for what we covered, it really is the interaction that is priceless.  Though I’m referring principally to hands-on workshop demonstrations, a subject that comes up frequently is how best to advise parents to obtain a consult with a developmental optometrist.  To steer clear of school system and health care politics, I suggest that therapists simply guide parents to the wealth of information at http://www.covd.org, http://www.oep.org, http://www.aoa.org and http://www.visionhelp.com.

Build it, and they will come.  Interact, and they will process the facts – with the public as the ultimate beneficiaries.

- Leonard J. Press, O.D., FCOVD, FAAO

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Letter Reversals…Does my child have dyslexia or a vision problem?

When a child confuses and reverses letters, such as “b’s” for “d’s” and “p’s” for “q’s”, parents often wonder, “does my child have dyslexia?”. This is largely due to the fact that the media has drawn public attention to a problem in visual perception where the person who reverses their letters or numbers usually has trouble reading effectively. However, dyslexia is a broad term that indicates an unexpected reading disability that exists in a person who otherwise has no cognitive impairment and has had adequate educational instruction. The causes can vary as outlined in Wikipedia’s review of dyslexia. A more general overview of “Vision and Dyslexia” has been written in a White Paper by the College of Optometrists in Vision Development.

Letter reversals are developmentally normal up to age 7, however several other developmental factors must be considered before assuming that a child is experiencing normal letter reversal tendency’s at a younger age. When a child is behind in their visual processing it is referred to as a delay in visual spatial orientation or visual directionality. A child who is developmentally delayed in visual directionality will exhibit confusion in reading simply because of the letters that are symbolically the same, have a different meaning because of their visual spatial orientation, ie,  “b”, “d”, “p” “q”…same symbol different meaning!

Delays in the visual brain’s ability to process information, such as letters, numbers and words, based on visual-spatial orientation,  will indeed complicate reading, writing and other learning activities. As a result, a child or adult who has this form of visual processing problem will also have a vision related learning problem. And yes this can be one of the causes for a reading disability or dyslexia…visual spatial dyslexia.

What should you do if you suspect your child has a problem with visual spatial orientation skills? Seek out help from a Doctor of Optometry who is Board Certified in Developmental Vision and Vision Therapy. Those doctors skilled in the diagnosis and management of a patient with these problems will utilize a complete battery of visual perceptual tests and be able to offer treatment, in the form of office-based vision therapy to treat and remediate the patients delay in vision.

To help doctors with the best methods of practice in treating patients with learning related vision problems, the American Optometric Association has published an evidenced based Clinical Practice Guideline entitled:Care of the Patient with Learning Related Vision Problems (CPG20)

The best treatment for a child (or adult) with a vision related learning problem is office-based vision therapy. An example of one of our patients success, ie “no more reversals”,  can be seen at Hannah’s Story.

Dam L. Fortenbacher, O.D, FCOVD

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