While our peripheral vision is always there, we generally don't think much of it. Now, thanks to a new professional study just released to the public, more and more people are getting interested in the science behind our differing ranges of peripheral vision.
12 people took part in this multi-year study. Researchers measured the group's peripheral vision using many visual field tests.
In one of these tests, participants were asked to stare at a red dot in the center of the screen. Throughout the test, researchers illumined the image of a clock on the right, left, top, or bottom of the screen. The clocks furthest away from the central dot were large and they got progressively smaller as they neared the center. Participants were asked to identify which way each clock's arrows were pointing.
It was more difficult for most respondents to figure out the times on the clocks closer to the center. This visual phenomenon is known in the medical field as "visual crowding."
While everyone's results were slightly different, researchers found that most had trouble perceiving objects above the center of vision. However, there was no uniformity in the team's findings, highlighting how different our peripheral vision "islands" are.
Researchers noted that most of the participants in the study had difficulty seeing objects above or below their eye level in crowded environments. Interestingly, most of the people involved in this study didn't have as much trouble seeing objects on their sides in the same environments.
This finding could have big implications for how city planners think about traffic safety. Dr. John Greenwood, a lead author on this study, said that this study proved how a truck driver would have more difficulty perceiving pedestrians at street level in a high cabin than if he was on the pedestrians' level and they were to his sides.
Professors involved in this research discovered that the patients' "islands" of poor vision affected every task they were asked to perform. This is interesting because some of the tests in the study were specifically designed to test different areas of the brain.
The medical community is currently divided on whether our peripheral blind spots are more so the result of nature or nurture. However, this study suggests that our differences in visual perception might develop in the early stages of our visual system.
Although visual crowding doesn't tend to affect most people's central vision all that much, there are a few serious conditions where this is an issue. These conditions include the learning disorder dyslexia and amblyopia (aka "lazy eye").
Another author on the study, Professor Patrick Cavanagh of Dartmouth, said this new report will help "better understand the mechanisms that cause visual crowding and where these occur in the visual system." He is also hopeful that this study will help develop therapies for people with serious visual issues like amblyopia.