
A normal person has a pretty wide visual field. They can see 60 degrees inward (toward their nose), 100 degrees outward (away from their nose), 75 degrees below the horizontal, and 60 degrees above it. If you’re having trouble imagining what those numbers really mean, think about how you can often see something “out of the corner of your eye.” This ability is related to the height and width of your visual field.
But for those whose visual field is contracting, this is an impossibility. Rather than the panorama that most of us are used to, seeing for them is more like looking through a tunnel. As you might imagine, this inability to see anything that isn’t right in front of you can make even simple tasks daunting. Those with a severe visual field contraction often have trouble finding and keeping a job.