It’s no secret that a number of body systems start to decline as you get older. Between aching knees and trouble hearing, aging can seem like a pretty raw deal. But new research is showing that the ravages of age aren’t always as permanent as we assumed them to be. New research released this week has found that some of the vision problems older adults experience may be reversible with the right kind of training. The findings give new hope that some of changes seen in the twilight years may be surmountable problems.
What causes vision to get worse in old age?
There are many causes of vision loss in old age. Diseases like age-related macular degeneration can cause damage to and deterioration of the sensitive light receptors in the retina of the eye. Other diseases, like cataracts, prevent light from penetrating through the eye so that the image that reaches the retina is distorted and fuzzy. While treatments are available for some of these diseases, medicine is still catching up with the wide array of things that can go wrong as we age.
This isn’t the whole story, though. It’s also well known that certain aspects of vision get worse in older adults over time even without disease. As we age, our ability to distinguish between different shades of the same color, also known as contrast sensitivity, gets worse. The sharpness of the image we see, also known as visual acuity, also declines. While the changes can seem minor at first, they can make it more difficult to read signs from a distance while driving or to notice a carpet on the floor that matches the floor’s color. The result is more driving accidents and more falls in older adults with these visual problems.
How did the researchers study this problem?
The researchers recognized that loss of contrast sensitivity and visual acuity probably had more to do with the processing of information in the brain than malfunctioning of the eyes. Older adults might have no disease but still struggle to see the world the way younger adults do. As a result, the team wondered if they could train older adults to get better at these two functions by teaching them to better differentiate between close colors and make out fuzzy images.
To do this, they brought in older and younger adults and had them train on a visual test for an hour and a half per day for a week. Participants looked through a viewfinder at a gray screen. In the middle of that gray screen was a striped patch of black and white, called a Gabor patch. The viewer was shown a patch in one orientation and then shown a second patch. The viewer then had to say whether the lines on the second patch had rotated to the left or to the right in reference to the first patch. The better a person was at the test, the harder the researchers made it by making the black and white stripes grayer and closer in color. This allowed them to constantly push each person to limit of their visual abilities.
What did they find?
At the beginning, the older adults were significantly worse at the test than the younger adults, which confirmed what the team already knew. The surprise came when, after five days of training, the older adults caught up to the younger ones such that there was no significant difference in their performance. Both contrast sensitivity and visual acuity improved in both groups, which translated into better apparent vision when tested with a letter chart at a distance. When the researchers examined the eyes of the participants, they found there was no change in the way the eye itself was working, indicating that the changes to improve vision had happened in the way the brain processed information.
How does this affect me?
These findings don’t change the course of eye diseases that affect older adults, but they do indicate that not all vision change is permanent as we age. The gains seen in this study may translate into the development of real trainings that could be done with older adults to stave of vision loss and keep them safer and more independent well into old age.