In this video, the beeps make you see something that isn't there

In this video, Caltech demonstrates the Rabbit Illusion, a "time-traveling illusion trick." It tricked me.

Caltech researchers have developed these two new illusions that reveal how the senses can influence each other-in particular, how sound can give rise to visual illusions. These illusions occur so quickly that they illustrate a phenomenon called postdiction (as opposed to prediction) in which a stimulus that occurs later can retroactively affect our perceptions of an earlier event.