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Brock String


Learn to see with both eyes simultaneously using the Brock string!

The Brock String is a powerful vision therapy tool that is very frequently used during the treatment of different forms of convergence problems, such as Convergence Insufficiency, as well as for patients with amblyopia and strabismus. Children with reading problems or those who are slow readers often have problems with convergence.

While relatively simple in design (the Brock string is made of a rope with 4 different colored beads), it is a very powerful tool in vision therapy. It helps to both diagnose and determine different binocular dysfunctions, and it is also a treatment solution, which helps strengthen patients’ binocular function and eye collaboration. Despite being primarily associated with binocular vision, we can also help strengthen fixation under binocular conditions.

Convergence problems




Simple and effective!

Use it at home!

Fun while training!

What to use the Brock String for?

The Brock string is often used in vision therapy for patients with vergence disorders such as Convergence Insufficiency, patients with Amblyopia (also called Lazy Eye), and for patients with Strabismus. This is important because these problems can contribute to headaches, blurry vision, balance problems, and more, but these can also be symptoms that can be caused by a concussion. The Brock String Test really looks at two different things: convergence and suppression.

Convergence is when both eyes are looking forward and an object is moving closer and you have to almost cross your eyes. If you are not converging, then one eye remains looking forward instead of meeting with the other eye. If this is one of your problems, then you may be seeing double.

Suppression is when your brain has decided to ignore the signals from one of your eyes which are being transmitted to the brain. In this case, you will just see one field of vision, and it may influence your balance and your peripheral vision.

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Get your Brock String!

AmblyoPlay vision therapy is an innovative approach to treating amblyopia, strabismus, CI and others. However, if in addition we pair it with some other traditional approaches, the progress only improves! The Brock String is a powerful vision therapy tool that addresses the same problems in an analogue way. Together, AmblyoPlay and the Brock String provide the best vision therapy outcomes.

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Why Do We Suggest a Minimum Time of 6 Months for Success?

Based on the data from over 15,000 patients using AmblyoPlay, improvements start within 4 months, while optimal results take anywhere between 6-18 months on average. The duration of required training depends on the patient’s age, the severity of the problem, accompanying diseases, and adherence to the training program.