Infants Anticipate the Timing of Sounds From Dynamic Collision Events

In everyday perception, expected sounds are predicted by the movement of dynamic objects. Here, we asked if four-to five-month-old infants' understanding of physical events allows them to use motion to predict the timing of collision sounds. We investigated whether infant looking time differed when viewing collision events that resulted in amodal visual or multimodal audio-visual changes. In a moderated, online study, we showed two groups of infants a moving 2-D ball and collision events. In one group, we presented infants with alternating trials from two conditions that varied in the temporal congruence of the ball's motion and collision sounds: one in which sound occurred simultaneously upon collision between the ball and a barrier (audio-visual; AV synchronous), and one where sound came slightly before collision (AV asynchronous). Another group of infants viewed the ball changing color upon collision (visual color change; VCC synchronous), and one in which the color changed slightly before collision (VCC asynchronous). Offline behavioral coding of recorded looking time demonstrated that infants looked longer toward AV asynchronous trials than to AV synchronous ones. This pattern was not seen in the group of infants who viewed color changing collisions. We also observed that infants looked longer toward AV asynchronous trials compared to VCC asynchronous trials. These data demonstrate that young infants have expectations regarding the temporal alignment of collisions and sound, which may provide a foundation for physical inference and learning in natural sensory environments.