What is akinetopsia?
Akinetopsia is a rare neuropsychological condition characterized by motion blindness. It affects a person’s ability to perceive motion within their visual field. Some people with akinetopsia see things in stop-action motion. For others, objects may seem to vanish and then reappear.
Normal motion perception allows the brain to recognize when objects are in motion. When akinetopsia occurs, this perception has been disrupted. Akinetopsia is a type of visual agnosia. It is a visual processing disorder (a condition that affects how the brain processes what a person sees). This means the brain has trouble understanding the information taken in through the eyes. Motion blindness may occur in varying degrees.
The word akinetopsia comes from the Greek language. A means “not,” kine refers to “move” and opsia translates to “see.” It is an acquired condition, which means it isn't inherited or present at birth. It can occur when the visual processing area of the brain is damaged.
Motion blindness can impact an individual's ability to complete day-to-day activities, such as:
Cooking
Reading
Playing sports
Watching television
Driving
In some cases, the effects may be mild and not interfere with routine activities. Individuals with motion blindness can usually still see stationary objects.
Types of akinetopsia
Akinetopsia is classified based on the severity of the condition and its effects on motion perception. Two primary forms have been identified.
Frozen frames
This form of akinetopsia is referred to as cinematographic vision or inconspicuous akinetopsia. Individuals with cinematographic vision see motion like a movie reel as if freezing frame by frame. Strobe-like effects may also occur. It is the least severe and most common type of the condition.
Vanishing objects
The second form of akinetopsia, also known as gross akinetopsia, is more severe and refers to the invisibility of moving objects. It involves the complete inability to perceive motion. Objects may seem to vanish once they move. Gross akinetopsia is extremely rare.
Akinetopsia vs. Zeitraffer phenomenon
Zeitraffer phenomenon is a condition similar to akinetopsia that affects motion perception. It impairs the brain’s ability to determine the speed at which objects in the visual field are moving. With this condition, objects may appear to move in slow motion.
