Visual tracking is the neurological ability of the eyes to follow a moving target smoothly and accurately. This fundamental skill allows the visual system to maintain a clear image of an object as it moves across the field of vision or to efficiently shift gaze between stationary points. It influences nearly every activity that requires coordinated sight and action, and its development is necessary for a person to effectively interact with their environment and manage tasks from reading a book to playing a sport.
The Underlying Process of Eye Movement
Visual tracking relies on two primary, coordinated types of eye movements controlled by the brain: smooth pursuit and saccades. Smooth pursuit movements allow the eyes to follow an object along a continuous path, keeping the image of the moving target precisely on the fovea, the area of the retina responsible for sharp, detailed central vision. This movement is deliberate and steady, ensuring the visual image remains clear even as the target moves.
When the smooth pursuit system cannot keep up with a fast-moving object, or when the gaze needs to shift quickly between two separate points, the brain initiates a saccade. Saccades are rapid, ballistic jumps of the eyes that quickly reposition the fovea from one target to the next. They are necessary for activities like reading, where the eyes must jump from word to word across a line of text. The interplay between these smooth and jerky movements maintains continuous, clear visual input.
Visual Tracking Developmental Milestones
The ability to track objects begins to develop shortly after birth, a progression crucial for overall neurological development.
Newborn to Six Months
In the newborn to three-month period, infants begin to develop visual awareness, starting with brief fixation on objects 8 to 12 inches away. By around two months of age, babies can briefly track a moving object with their eyes, though the movement is often jerky and limited to peripheral vision. Between three and six months, visual tracking improves dramatically as eye muscle control strengthens and the eyes begin to work together effectively. Around the four-month mark, infants follow objects more smoothly and accurately, and the eyes can move independently of the head. The ability to track across the midline, the imaginary vertical line dividing the body, also emerges during this time.
Six Months and Beyond
By six months and into toddlerhood, a child’s visual tracking skills become well-established and integrated with motor skills. Depth perception develops, allowing for better judgment of distance, which is necessary for anticipation and grasping. This mastery enables coordinated head and eye movements and establishes the groundwork for complex visual tasks like searching for a hidden object or watching an object fall.
Impact on Learning and Coordination
Effective visual tracking is a foundational skill that impacts a wide range of academic and physical activities. In reading, precise eye movements are necessary to track lines of text without losing one’s place, skipping words, or jumping lines. Poor tracking can lead to excessive head movement while reading, reduced reading comprehension, and the need to use a finger as a guide.
Beyond the classroom, visual tracking is fundamental to motor coordination and athletic performance. Hand-eye coordination relies on the ability to track a moving object, such as a ball, with speed and precision to intercept it. This skill is necessary for judging distances and navigating an environment without clumsiness. Visual input also feeds into the systems governing balance and gait, helping to maintain stability during movement.
Evaluation and Training
Visual tracking issues, sometimes referred to as oculomotor dysfunction, can be identified through specialized professional assessments. Standard 20/20 eye exams only measure visual clarity and do not evaluate the coordination of eye movements. Developmental optometrists use a combination of qualitative chairside observations and quantitative, standardized tests to measure fixation, smooth pursuit, and saccadic accuracy.
For individuals identified with a tracking deficit, treatment often involves a customized program of vision therapy. This therapy uses specific eye and brain activities to strengthen the neurological connection. Simple, practical activities can also help stimulate and enhance these skills, such as tracing complex patterns, following a light or toy with the eyes, or playing ball-catching games.