Infants' Perception of Semantically Defined Action Role Changes in Filmed Events

In this study, 50 infants (15 to 18 months of age) were shown four different film sets in an effort to determine (1) whether infants can perceive action role reversals between an actor and recipient of the action when the direction of the action is ruled out as a cue and (2) whether infants consider only animate objects to be potential action-agents. These questions were based on the assumption that language acquisition is based on a cognitive non-linguistic foundation of concepts, categories and meanings. Films were made depicting first standard, then reversal, events. The standard events consisted of repeated trials of actor A (a male actor) pushing actor B (either another male actor or a chair), with position and direction alternating. In the role reversal events, actor B pushed actor A, again with position and direction varying. Visual fixation and heart rate were measured while infants viewed the films. Data from 26 of the subjects were used, since data from the other subjects were unusable due to fretting, excessive moving or equipment failure. Results indicated that action role reversals are perceived by infants regardless of changes in the direction of action; there was little evidence that infants consider the category of agent to include only animate objects. The implication of the findings in relation to language learning is discussed. (SB)