Experiencing black shapes or figures at the corner of your eyes, commonly referred to as "peripheral vision disturbances," can have several explanations, and it doesn't necessarily mean you have a history of insanity or hallucinations. In fact, these experiences are quite common and usually have benign reasons. Here are some potential explanations:
Eye floaters: Floaters are small, semi-transparent or dark specks or shapes that drift around in your field of vision. They are caused by tiny clumps of gel or cells inside the vitreous, the jelly-like fluid that fills the inside of your eye. These floaters can cast shadows on the retina, which you may perceive as black shapes or figures at the corners of your eyes.
Visual snow: Some individuals experience a phenomenon called visual snow, which involves seeing tiny, flickering dots or static-like interference across their visual field. This condition can sometimes create the illusion of shapes or figures, particularly in the peripheral vision.
Migraine auras: For some people, migraines can be preceded or accompanied by visual disturbances known as auras. These auras can manifest as shimmering or zig-zagging lines, flashing lights, or even dark spots in the visual field, which might be perceived in the periphery.
Eye fatigue or strain: Prolonged use of digital devices, reading, or engaging in other visually demanding tasks can lead to eye fatigue. This can cause momentary distortions in your peripheral vision, resulting in the perception of shapes or figures.
Optical illusions: Our brains sometimes interpret patterns or shadows in the environment as recognizable shapes or figures, even when they aren't actually present. This is a natural quirk of our visual processing system.
Sudden movements or flickering lights: Peripheral vision is particularly sensitive to detecting movement, and sudden movements or flickering lights in your surroundings can create fleeting shadows or shapes.
Hypnagogic hallucinations: If you experience these visual phenomena primarily when falling asleep or waking up, they might be attributed to hypnagogic hallucinations, which are vivid and dream-like experiences that occur during the transition between wakefulness and sleep.
In most cases, these experiences are not a cause for concern, especially if they occur only occasionally and don't interfere significantly with your daily life. However, if you are concerned about your visual disturbances or they become more frequent or intense, it's always a good idea to consult an eye specialist or healthcare professional for a thorough evaluation and peace of mind.