Vision and Your Brain

You probably think of your visit to your optometrist as a time to ensure you are seeing as well as possible. You probably believe seeing the smallest line on the test chart is all you need to do to have excellent vision. What makes us humans different to most other species on the planet is our ability to see in 3D. It’s still possible to function at a high level with only one eye but it is much harder than when using stereoscopic (3D) vision. When we use 3D vision we can very accurately know where we are in our visual world. That might seem a rather strange idea but, if we don’t know where we are, we cannot move around safely. Driving would be like playing on the circus dodgems with everyone crashing into each other. Pouring boiling water into a cup of coffee would be extremely dangerous as it would be very difficult to accurately judge the exact position of the top of the cup.

Our brains have evolved to enable us to have extremely accurate 3D vision. Sometimes things can go wrong and suddenly we can find our visual world turned upside down. Children with reading problems very frequently have undiagnosed defects in their 3D vision system. If you have suffered from concussion you might have found it hard to focus or to judge distances. Likewise patients who have had a stroke can find their vision very difficult to cope with.

In previous articles I have discussed how it is possible to rewire our brains. Gone are the days when I had to day to a parent their child with the lazy eye would never see any better. Likewise it is often possible to help patients with brain injury to minimise any deficit caused by their injury.