Blinking is another indication that vision is partly a product of energetic immateriality.
Human blink both eyes synchronously. Some animals, including tortoises and hamsters, independently blink their eyes.
Though blinking rate varies considerably, depending upon emotional and mental states, humans blink their eyes about every 4 seconds. A blink lasts 1/10th of a second.
Eye blinks cause disruptions to visual input and are accompanied by rotations of the eyeball laterally by 0.5° or 1.0°. Like every motor action, these eye movements are subject to noise and introduce instabilities in gaze direction across blinks. ~ Gerrit Maus et al
Visual imagery remains constant despite the frequent outages and misdirection in eye movement caused by blinking. This cannot be accomplished through purely physiological means.
The material paradox of consistent vision despite blinking is brought home by the fact that there must be image consistency at least every 13 milliseconds not to detect jitter; far faster than the time it takes the eyes to blink. The threshold rate at which flickering light is perceived as steady is known as the flicker fusion threshold.