What do you call the the effect that causes people to miss the "the the" in this title?

Question

Ages ago someone told me that most readers will not spot a double-the in a sentence. Something about the way we process words apparently filters out the extraneous "the" but I don't know what that process is called. Does it have an explicit term? What is it?

Answer 1

There might be several terms to describe the phenomenon. But you can research your questions by looking up the term "repetition blindness".

Answer 2

This is commonly referred to as perceptual blindness--where the attention of an individual is adverted away from a particular scene. According to C Tseng, inattentive blindness results from a lack of attention that is not associated with vision defects or deficits, as an individual fails to perceive an unexpected stimulus in plain sight.