Figure 5.

Multiple object tracking: The task began with a subset of red (gray in figure) circles (2, 3, or 5) that moved randomly among moving green circles (black in figure). The red circles turned green after 2 seconds, at which point participants continued tracking them. After a 5 second tracking interval, the circles stopped, and a single circle turned white with a question mark. Subjects were to respond via keyboard with a YES/NO response whether the white circle was previously red.