Figure 2. Selected frames from the test event used in Experiment 1.

Infants first saw the two donors, familiar from the previous familiarization events, on the lower part of the screen. A new agent, an orange circle with eyes and mouth, entered from the middle of the upper part of the screen, moved down and stopped between the two donors for 0.5 seconds before it started to hit one of the two donors repeatedly for three times, each time pushing it farther away towards one of the lower corners. After the third hitting, the orange agent returned to the central position (arrows are inserted to illustrate the agent's motions).