Find your manners: how do infants detect the invariant manner of motion in dynamic events?

Abstract

To learn motion verbs, infants must be sensitive to the specific event features lexicalized in their language. One event feature important for the acquisition of English motion verbs is the manner of motion. This article examines when and how infants detect manners of motion across variations in the figure's path. Experiment 1 shows that 13- to 15-month-olds (N = 30) can detect an invariant manner of motion when the figure's path changes. Experiment 2 reveals that reducing the complexity of the events, by dampening the figure's path, helps 10- to 12-month-olds (N = 19) detect the invariant manner. These findings suggest that: (a) infants notice event features lexicalized in English motion verbs, and (b) attention to manner can be promoted by reducing event complexity.

Figure 1

Six manners were created for the experiments. Each of the six manners are shown here as static pictures on a 2 s timescale, though they were presented as dynamic events.

Figure 1

Six manners were created for the experiments. Each of the six manners are shown here as static pictures on a 2 s timescale, though they were presented as dynamic events.

Figure 2

Five paths were created for the experiments. The X depicts the starting and ending points for each of the five paths, while the dotted line shows the path the figure followed.

Figure 3

The child sits on his or her parent’s lap in front of a large television screen. A camera to the left of the television screen records the child’s looking preferences to the visual stimuli, while a video camera to the right of the television screen plays the visual stimuli.

Figure 4

Top graph shows infants’ looking times during the familiarization trials for Experiment 1. The y-axis shows average looking time in seconds (out of 12 s). Infants in both age groups showed a linear decline in their looking times during the familiarization phase, however infants from the two age groups did not differ in their attention to the familiarization events. The bottom graph displays infants’ looking times during test trials for Experiment 1. The y-axis depicts the average novelty-preference scores. A number greater than .50 indicates a preference for the novel event, while a number below .50 indicates a preference for the familiar event. Only the 13-to 15-month-olds showed a significant preference for the out-of-category test event. *p < .05.

Figure 5

Top graph depicts infants’ looking times during the familiarization trials for Experiment 2. The y-axis shows average looking time in seconds. Infants’ looking times during the familiarization phase did not show a significant linear decrement. The bottom graphs reveals infants’ looking times during test trials for those 10- to 12-month-old infants’ participating in Experiment 1 and those infants participating in Experiment 2. The y-axis depicts the average novelty-preference scores. Infants participating in Experiment 2, in which the ground object was removed, looked longer at the novel, out-of-category event during the test phase. *p < .05.