Transient attention
Research using Rapid Serial Visual Presentation (RSVP) suggests that visual targets can be rapidly detected. When a target is spotted, a temporal window of attention to encode that target stimulus into memory. The time course of this transient attentional enhancement is about 150 milliseconds, so it is possible for a following stimulus to benefit from the attention deployed to an earlier one. This is demonstrated in the following paper
Attentional blink
The term attentional blink describes the finding that it is hard to see two stimuli in rapid succession (about 200-400 milliseconds apart). Under these circumstances, it seems as if our attentional system “blinks” and a target that is plainly visible to the eye goes undetected by the mind. However, when two targets are presented more closely in time, it is quite easy to see both of them, a puzzling phenomenon known as lag-1 sparing.