Tunnel effect

In experimental psychology, the tunnel effect occurs where two lights set apart and appearing sequentially appear to move through an intoduced screen, placed between and in front of them,, as though they had gone through a tunnel. It is the perception of a single object moving beyond an occluding object and then reappearing after a suitable amount of time on the other side of it. The effect continues if the screen is removed. Interestingly if the observer is unaware of the screen the illusion does not occur

The phenomenon has been studied by Burke (1952), who discovered that the optimal amount of time for giving the impression of a single object is shorter than what is actually needed to cross the occlusion at that speed.

It is an example of a kinetic screen effect similar to the piston effect