Learning is primarily a visual task and knowledge will be shared in varied forms this year. When your child is doing school work at home, make sure that they are set up for success. Just like the proper ergonomics for lifting a box, our visual system performs optimally and is less likely to experience stress under the right conditions.
Desk & Chair
Let’s start with the hardware. When seated at a desk, the feet should be able to rest flat on the floor when the back is pushed to the back of the seat. This will create three 90-degree angles in the ankles, knees and hips. If your child’s feet do not touch the floor, use books under their feet to achieve a 90-degree angle.
Using a slant board will move materials in line with the face to improve reading. Research has found this angle to be 22 degrees. I imagine that you rarely carry a protractor so instead imagine that you’ve picked up a book to skim the cover in a bookstore—how you are holding the book is likely very close to 22 degrees naturally as this is the most comfortable for our visual system.
The optimal viewing distance for reading and near work is called Harmon’s Distance. This is the distance between a closed fist resting just under the chin and the elbow. The distance will be slightly different person-to-person depending on size. This allows the eye focusing mechanism to perform optimally. Even a few centimetres closer will start to ramp up the demand on the system and increase eye strain and fatigue.
In my 10 years in optometry, I have often heard the question: “Will reading in the dark hurt my eyes?” The answer is no…but yes. Although it will not structurally hurt an eye, it certainly will cause your child to bring the pages closer to see, and in turn, increase eyestrain. A directional light, for example a desk lamp, will allow your child to evenly light the page.
Our visual system was not designed for long periods of near work. Taking frequent breaks will prevent it from getting “locked” on the near task. The 20/20/20 rule works well: every 20 minutes, take 20 seconds to look 20 feet away. These short breaks reduce the tendency of the focusing muscles to become cramped.
Even though the weather is about to change, active outdoor play is still an important part of visual development. An hour of distance play outside has been shown to be protective against the development of near-sightedness.
Of course, all these efficiency factors are not terribly important if your child cannot see well. An eye examination looks at not just the sharpness of letters, but at overall eye health. Glasses can help visual systems for reading or to improve sleep cycles by blocking blue light from screens. Keep in mind that although vision screenings are useful, they are not a replacement for an assessment with your optometrist.
So good luck to us all in the new school year!