Encountering obstacles or having reading difficulties
The feeling of looking through a veil or the sensation that part of your field of vision has disappeared can occur after a brain injury. This phenomenon, called hemianopsia (or quadrantanopsia when only a small part of the left or right field is affected), can be temporary or permanent.
Some patients are not aware of this impairment and do not understand why they bump into obstacles or have difficulty reading. Others just feel a visual discomfort or complain of having lost the sight of one eye only. For example, a person with right hemianopsia may not see their right foot when walking and have difficulty finding products on the right side of the supermarket. They also notice that reading has become difficult because the end of each word is hidden by the hemianopsia.
Right lesion, left field affected and vice versa
When the left visual field is affected, the phenomenon is attributed to a lesion on the right side of the brain. Conversely, when the right visual field is affected, it is due to a brain lesion located on the left side. This is because the fibers in the brain cross over, and each cerebral hemisphere controls the opposite visual field. This is not a problem with the eyes, but rather with the connections between the eyes and the brain.
Move the head and gaze to search for the missing information
To compensate for this restricted field of vision, it is important to develop the habit of moving your head and eyes to seek out the missing information. It is also possible to arrange your environment to place important elements on the preserved side.