Attention

Seeing is not looking.

Selective attention

Only a fraction of what reaches the eyes is processed deeply. The invisible gorilla study showed people counting passes miss an obvious figure walking through the scene.

Change blindness: large changes go unnoticed without attention.
Inattentional blindness is a normal feature, not a defect.

Consequences

Driving while distracted, missing a warning on a familiar screen, and eyewitness unreliability all follow from the same limit.