Summary:

- The human eye and brain have limitations in perceiving fast-moving objects, such as lightning. This is due to a phenomenon called "saccadic masking."

- Saccadic masking occurs when the brain suppresses visual information during rapid eye movements (saccades) to prevent blurred vision. This allows the brain to process the visual information more effectively.

- As a result, the brain may not be able to detect or perceive some fast-moving events, like the initial flash of lightning, even though they are physically present in the visual field.