How Long Can the Human Eye Focus on a Single Point?
While it may feel like you are staring perfectly still at a single dot, the human eye is physiologically incapable of locking onto a target without moving. If the eye were to stop moving completely, you would go blind in a matter of seconds. In reality, what we perceive as a steady gaze is actually a series of microscopic jitters. Clinical data on fixation stability shows that a healthy eye performs a continuous dance of three distinct movements: tremors, drifts, and microsaccades. Even during intense concentration, the eye constantly vibrates within a range of 1 degree of visual angle to refresh the retinal image.
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