Following the overall awareness of one’s surroundings that is greatly dependent on Peripheral Vision, Depth Perception - the simple existence of it and the level of its development - is the second most critical eyesight skill in sports.
Depth perception, often referred to as 3D vision, is one’s ability to see dimension in their surroundings. Without it, the world, including the game field, looks flat and the player has difficulty estimating how far objects are relative to where the player stands, judging distance between objects, or assessing the exact position of objects on the field. Depth perception makes it possible to analyze the game and quickly answer questions such as: How far is the ball? Can I reach it before my opponent gets there? What direction and with what strength should I pass?
Depth perception is delivered within the area of the vision field that both eyes are able to see. The area where the vision of the right eye overlaps the vision of the left eye (double eye vision / binocular vision), which is about a 120° angle of space. The rest of vision is monocular, seen with only one eye.
A key pre-requisite for a well developed depth perception is the presence and the quality of binocular vision. Ultimately, your eyes must work together in tandem to transmit two separate images to the visual cortex of the brain where they can be correctly converted into one in a process called fusion. In order for the fusion to happen, the eyes must look in the same direction, track together and with the same strength, meaning that neither eye is lacking acuity and making the other eye do all the work.
TRAINING ONE EYE AT A TIME
Skill development that requires building new neural path connections between the body and the brain often benefits from a step by step approach. Take for example a pianist learning a new piece of music. They practice the part played by the right hand first, then the part played by the left hand. Only when each hand is familiar with the moves can the pianist play with both hands. Another example is a taekwondo form. Each form is composed of a series of moves that must flow seamlessly one after the next, so that if and when they are used in real life self-defense situation, they happen nearly automatically. The student of the art practices each move on its own before putting the form together. In fact the whole idea of the belt levels (from white to black and beyond) is based on building upon previously learned skills.
Vision training is no exception to this rule. One of the critical steps in eyesight development is to give each eye a chance to engage with the stimuli and connect with the visual cortex on its own. That way each eye can develop the desired interpretation of the visual signals (new neural pathways) independently before being confronted with the need to work in harmony with the other eye.
Much of the drills in this part of the Performance Training are recommended to be performed with each eye separate, starting with the athlete’s Dominant Eye. Only when the mono eye practice is successful is the athlete encouraged to complete the same practice with both eyes at the same time. Ironically, this dual (two step) approach of single eye practice ultimately leads to a much better collaboration of the two eyes, and to stronger binocular vision.
KNOWING YOUR DOMINANT EYE
Minus rare exceptions, each person has one eye that leads and one that follows. The leading eye is called the Dominant Eye.
Dominant eye does not necessarily mean one that sees better, but it often does determine the way the two eyes work together. Knowing which eye is your dominant eye is useful for single-eye practice, as it is often easier to train the dominant eye first, and only then practice with the other eye. The dominant eye may be able to grasp the drill faster and through the use of imagination show the other eye the way to improvement. As an athlete, you know that showing your mind the desired outcome by simply imagining it makes any goal much more achievable. So, if one of your eyes performs better than the other, simply imagine the less proficient eye acting in the same manner as the more proficient eye, then practice and see what happens. Repeat the process as many times as necessary. Be positive, kind and patient.
DETERMINE YOUR DOMINANT EYE
Stand with your arms stretched in front of you and your hands overlapping, creating a small triangle between the thumbs and second fingers
With both eyes open, find a small object in the distance and see it through the triangle
Then, without moving your arms, hands or head, close one eye and notice whether the eye that remained open can still see the object as before
Switch eyes and notice whether the eye that remained open can still see the object as before
Most likely one of the eyes saw the object and the other lost it. The eye that was able to see the object is your dominant eye
Watch outs:
You must not move while determining your dominant eye. The only movement that happens is your left eye closing, then your right eye closing
If you move your head or your arms/hands, you will not be able to tell whether the object stayed or disappeared
WHAT IF YOU CANNOT SEE 3D
Binocular vision development can be more difficult than other eyesight training, especially if it is fully missing or severely lacking. It may take time, discomfort, perseverance and trust in the process. With that said, the reward for those who succeed is a new view of the world (and the field), and an exponential growth of their ability to play a sport.
If you do not see 3D at all or have severe difficulty with the drills, the following should be followed:
It is critical to prevent staring, trying hard and pushing through any discomfort. Perfect eyesight can only be reached through relaxed eyes. Practice with ease, close your eyes often to let them rest
Double up on the drills offered within the Depth Perception section of this program - practice more often and increase the repetitions
If the improvement does not show, you may need to engage in a fusion focused practice or a more personalized program. Much of binocular vision development can happen through techniques that are best to perform outside the team environment and often at home. Please contact Overbound should you be seeking more help in this area.