Couldn’t See It Happening ‘til It Was Too Late

The words you are reading right now are patterns of light hitting your eyes which trigger neurons to transmit this environmental information to your brain for development into an image. Everything you see is just brain interpretations of light in your surroundings. The pathways that visual information goes through from the eyes to the brain can be disrupted in different ways with results that would be surprising to most people. Aside from general vision loss, most people would say color blindness if asked to name a different type of vision disorder. These are both very commonly known, but color blindness reveals something about vision that most people don’t think about. There are separate aspects of what you can see that can be individually disrupted. One of these isolated aspects is motion.

Motion blindness, or akinetopsia, is a condition in which one can see clearly but only in still images. People with a severe version of this disorder have no flowing view of motion in their environment. When observing motion, they see 3D snapshots of the changes that occur. For instance, watching you walk towards them, they would see you 12 feet away for a moment, then another moment where you were instantly 8 feet away, then another moment at 6 feet away, etc. with no image of you moving through this distance. For some with this condition, they may even see several images of you simultaneously at various distances you have traversed. And this occurs not because of damage to the eyes, but because of brain damage.

The full image you’re detecting at any moment is a series of calculations your brain is making from the signals it receives via the sensory organs. Color, depth, shape, etc. are all distinctly evaluated aspects of the image. This evaluation is done in different areas of the visual pathways in the brain. The left and right eye each observe the environment within their field of vision and send this information to the brain. Each eye is observing the same things from a different position in relation to the viewer’s surroundings. The brain then forms a cohesive image based on analyses of differences between these two sets of light information. If damage occurs to parts of the visual areas of the cortex, these calculations are disrupted. Since the brain can no longer synthesize this information into a singular perception, it presents the sight in separate chunks.

It has been found that many people have motion blindness in some part of their visual field. But because the rest of their visual field functions correctly, their brain is still able to make the necessary calculations to produce an image with motion. Most people with partial motion blindness are never aware of it. But the extreme cases create significant challenges for individuals of this experience. For instance, pouring a beverage is difficult because one would not see the rising level of liquid in the vessel continuously. So the glass may be overflowing but you still see a half empty glass. A more dangerous complication would be crossing the street when one can’t track the motion of the cars passing by. Severe cases of akinetopsia present many functional difficulties in one’s everyday life. One could see how this disorder would be associated with anxiety. A very common type of scare in horror movies is the jump scare, and viewing life in this series of still images would definitely produce constant real-world jump scares.

Just think about how aggravating it is when you’re streaming a video with a bad connection and the action keeps progressing without the videos. You hear explosions and gunfire but you still only see a frozen image of a man walking his dog down a peaceful street. The computer is frozen so you can’t pause the video until it gets back to normal function. For some, this is how they experience everything. This is just one of many fascinating lesser known vision disorders. Studying them reveals how the brain operates as a machine to process our surroundings using the sense organs and have us respond accordingly, both in mental and physical terms.