Modified Brock String for Peripheral Vision

Published on
February 28, 2022

Brock string is commonly used in vision therapy which comprises a white cord or string that is about 10-15 feet long, along with colored wooden beads that move along the length of the cord. The brock string is used for central vision as well as improving peripheral vision. 

Why is it called Modified Brock string?

Typically, a brock string is used to test the ability of the eyes to focus on an object at various distances and therefore useful in working with patients who have issues like convergence insufficiency, amblyopia (lazy eye), and strabismus.

A modified  Brock string is the same tool with slight modifications and different exercises which enables it to be used as a tool to work on peripheral vision (side vision). 

What are some of the exercises included in the Brock string procedure?

  • The Brock String for Central Vision  - It is one of the most common procedures used in the therapy room to train binocular vision (both eyes working together). The patient will hold the string up to their nose and will be asked to focus on various beads and make the two strings cross at each bead. This is a central activity which means it is working on the central part of the vision.
  • The Brock String for Peripheral Vision - The patient may be asked to open their stance a little bit wider when they are having trouble opening their periphery, so they will move their feet apart and by opening their stance, they will be able to open their periphery a little bit more.

Another thing that is done for peripheral vision is to have the patient focus on the beads while the vision therapist brings their fingers over to the side and the patient's vision,             the patient is asked to move their fingers when this happens which forces them to be aware of their peripheral vision.

         Another exercise to develop peripheral vision with the brock string is to have the patient name objects that are in their periphery as they look at the beads. In cases where the              patient ignores one eye more than the other, they may be asked to tighten up or increase their muscle tone on that side. 

         Another way to increase peripheral awareness is to use lighted buttons, which light up intermittently and the therapist will set them on the table. Then, if it lights up on either             the right or left side of the periphery, the patient would tap that light to turn it off.


Why is the modified Brock string a powerful exercise to work on central and peripheral vision during vision therapy? 

When a patient is taught to combine both central and peripheral vision they are taught a valuable skill that is used in sports and reading. Their brain is now able to go back and forth from central and peripheral visual processes and organize that visual information. 

Contact Us To Amplify Your EyeCare

Amplify EyeCare Chattanooga Logo

Working Hours

Monday - Tuesday
7:30AM - 5:15PM

Wednesday - Thursday
8:00AM - 5:15PM

Friday - Sunday

1043 Executive Drive Suite #101 Hixson, TN 37343
(423) 710 3966
Website Accessibility Policy
Safety protocols page
privacy policy
phone-handsetcalendar-fullarrow-up linkedin facebook pinterest youtube rss twitter instagram facebook-blank rss-blank linkedin-blank pinterest youtube twitter instagram