Concussions Affecting The Visual System
Common sense tells us that vision is formed in the eyes.
That's not true.
The eyes take a picture, like a camera, and send it to the brain. It's in the occibital lobe of the brain where vision is actually formed. Then, impulses are sent out to other parts of the brain to help the mind and body respond to the information in the eyes.
A vision concussion disrupts how the brain recieves information from the eyes and how the brain responds to that information.
There are actually two streams of vision in the brain; the ventral vision stream and the dorsal vision stream.
25% of your vision's input into the brain is used in the ventral vision stream. This part of vision is responsible for recognizing objects such as the 20/20 letter on an eye chart, the picture on a computer or the text on your phone.
75% of your vision's input is used in the dorsal vision stream. This part of vision feeds into the brain in conjunction with information from the vestibular stream of your inner ear (relating to motion) and the proprioceptors (receptors in your joints) helping the brain realize the body's position in space.
How do concussions affect the brain?
The ventral stream: A concussion in this area causes blurred vision. It may also cause a change in the glasses or contact lens prescription. A change in the glasses prescription are recommend to help address this issue.
The dorsal vision stream: A concussion in this area causes symptoms including motion sickness,the surroundings in constant motion, the surroundings moving in strange color such as a kalidescope, difficulty riding in a car, and apprehension when walking into a crowd.
Have you ever been in a parked car in a parking lot, the parked car beside you slowly pulls out backwards, and you suddenly get the feeling that you and your car are moving forward? You've been tricked by your dorsal vision stream. This is why concussions of this area are confusing to patients and can take time to mend.
In Chapter 10 of my book, See To Pay: The Eyes of Elite Athletes, I also discuss how concussions affect the visual system. The reader learns about the dorsal vision stream and how this system works in concert other systems in the brain, such as the vestibular and proprioceptor system. I also discuss how visual systems can become injured by a sports related traumatic brain injuries.
By vision exercises and vision therapy, we have helped over a hundred athletes get back to normal so they can continue with school or work. A retrospective study on our protocol revealed that athletes who used our protocol returned to play in an average of 6 weeks, where it took 12 weeks for athletes who chose not to do vision therapy.
Athletes seeking this type of treatment can reach us at our Wakefield office in Raleigh. NC at telephone number: 919-847-4665. Also, you can find more information in the book, See To Play.
The following clips may aid you in the understanding of this type of concussion. This first is with Jay Harrision who sustained a concussion during a National Hockey League game.
The next story is in one of our local teen athletes in the area
Jay Harrison shares his vision concussion rehabilitation.
Watch a news article about a vision concussion from football that affected a 10 year old multi-sport athlete and how our concussion protocol helped him recover. Click here to watch
Here's Jay Harrison's full interview