Attentional blink
Attentional blink (AB) is a psychological effect where people struggle to notice a second visual target in a rapid sequence if it appears 200 to 500 milliseconds after the first and is followed by distractions. For instance, in a fast stream of letters like "B, X, C, K," if "X" and "K" are targets to spot, "K" is often missed if a letter like "C" comes between them.