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Who is Brock and why does he String?

Within the world of Vision Therapy, there is an exercise commonly used for people who suffer from Convergence Insufficiency, which is the inability to bring your eye posture in due to a misalignment in the eyes. This exercise is called the Brock String, which only requires two items, a string and three beads—the Brock String was created by Dr. Fredrick Brock, a Swiss optometrist.

The Brock String allows the user to bring both eyes together to make the focal point the bead. Doing so allows the user to learn how to bring both eyes together versus having one eye drift away. Common symptoms of eye misalignment may cause blurred or double vision, sore eyes, poor stamina when conducting close work activities, and poor reading and tracking habits. The Brock Sting can help users learn how to use their eyes properly in many ways!

The first activity that includes the Brock String instrument is called Bead Jumping. As the user has one end of the string attached to a stationary object, the other end will be held by the user against their nose. As the name implies, the user will be jumping from bead to bead with their eyes. By looking at the bead nearest, they should see an “X” like figure running through the center of the bead. Doing so gives the user positive feedback that they are doing this activity correctly. If the user sees the “X” before the bead, they are eye-teaming a bit too close than they should. While if they see the “X” behind the bead they are targeting, they focus a bit too far than they should. Once they can create this "X", the goal is to follow the same steps and get an "X" on the other beads attached to the string.

The Second activity with the Brock String is called Bead Sliding. This activity will require more demand from your eyes depending on if your eyes lay in an eso posture or exo posture. To perform this activity, the user will have the same setup with Bead Sliding however, only one bead is used. As the user places the bead at a distance that is not too far but not too close to the user's eyes, the goal is to be able to maintain the “X” that we saw in Bead Jumping, but now we will be sliding the bead slowly towards our face. Doing so helps our eyes learn how to be versatile, from fluctuating between our eyes being turned out to our eyes being turned in. Along with being able to eye team as well. Once the user has the bead close to their face while maintaining the “X”. The user will slowly bring the bead out again while keeping the “X” running through the center of the bead, ensuring that our eyes are always focused at one point in space.

Who knew a simple instrument could be so beneficial to our eyes!

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