I was lying down staring at the ceiling fan. The fan had a circular metal piece at the center and it had the radii with ridges. When the fan is on, I can't see the ridges, but all of us a sudden I felt I'm able to see the ridges for a fraction of a second. I realized I could see the ridges when I was blinking my eyes. I wasn't sure whether the vision of ridges precedes the act of blinking or the other way around.
The theory behind the persistence of vision is still being debated or debunked. Instead of banking on a theory, I have my own explanation.
As the fan center rotates at more than 24 cycles a second, the ridges are not visible. We can compare this to the movie watching experience where 72 or more still images are produced per second to create an illusion of motion. When I blink, as the last image captured by the eye is processed by the brain, it doesn't have a succeeding image to perceive a rotating circle. So, the last image is experienced by the brain as it exists - with the ridges. When the act of blinking ends, images of the rotating circle reach the brain continuously. So, the static image is experienced by the brain for just a fraction of a second.
I think there is some amount of slow-down in the way my brain processes the signals. I had more such experiences. In one instance, I could sense the experience of sound through my left ear was delayed by a fraction a second after I experienced the sound through my right ear.
I wish I could work with a neurosurgeon to understand the signal processing of the brain with such experiences.