Visual Tracking relates to eye movement ability and is also known in the optometric literature as “ocular motility” or “oculomotor function”. In general, this refers to the ability to quickly and accurately look (fixate), visually follow a moving object (pursuit), and efficiently move our eyes so we can fixate on objects from point to point as in reading (saccades).
This is a great animated representation, provided on the Neuro Optometric Rehabilitation Association website, of a visual tracking disorder:
As explained by Dr. Fortenbacher on the VisionHelp blog, the optometric testing of visual tracking is usually broken down into two general categories: Qualitative chairside observation and Quantitative (measurable) standardized tests. The standard 20-20 eye exam does not test any eye movements, including eye tracking. A person can pass the 20-20 eye exam and still have undetected eye tracking problems.
First, in the category of qualitative chairside observation, the doctor typically uses a fixation target like a pencil, pen, or toy object on the end of a wand and positions it about 8-10 inches in front of the patient’s eyes. The patient is asked to look at and follow the target with their eyes as the doctor moves it horizontally, vertically, and in rotation.
Quantitative tools that optometrists may use to show or measure tracking (and other) disorders include RightEye, the Visagraph, the Readalyzer, the King-Devick Test, and others. These are quick, non-invasive tests that are easy to administer. These tools are getting more sophisticated as technology evolves and research is now showing that eye movement tracking can help diagnose many vision and general health disorders.
People with visual tracking problems may be diagnosed with Oculomotor Dysfunction. Oculomotor Dysfunction is a common vision problem and occurs in people of all ages, both children and adults. Oculomotor Dysfunction affects reading, sports, balance, depth perception as well as most visually related tasks. Oculomotor Dysfunction is not a condition you can outgrow. Instead, over time, an individual develops compensatory techniques – such as turning of the head while reading, rather than the head remaining stationary while the eyes move across the page of text.
Treatment for Oculomotor Dysfunction usually includes a treatment program of vision therapy. Vision therapy involves using lenses, prisms, and specific eye and brain activities designed to improve fixation and saccadic eye movements; integrate oculomotor skills with vergence and accommodative systems; integrate oculomotor skills with information processing.
Because the symptoms of a visual tracking disorder are similar to many other disorders, it is commonly misdiagnosed. Unfortunately, even well-trained nurses, pediatricians, teachers, and other professionals fail to consider vision problems when they see children struggling to read, struggling to pay attention, or struggling to progress in school. They can also fail to see fidgeting, anxiety, and behavior problems as signs of undiagnosed vision disorders. Therefore it is important that school aged children are seen annually for a comprehensive visual assessment with an optometrist that tests binocular vision and visual skills in addition to acuity and general health of the eye.