Question

Participants were instructed to focus on either white or black objects, disregarding the other color. when a red cross passed across the screen, about one third of the subjects did not notice it.

Answer 1

The answer is inattentional blindness.  It is a mental absence of consideration that isn't related to any vision imperfections or shortages. It might be additionally characterized as the occasion in which an individual neglects to see a surprising jolt that is on display.