Infants' association of linguistic labels with causal actions.

Six experiments examined infants' ability to associate nonsense words with 2 causal actions: pushing and pulling. Although Experiment 1 found that 14-month-olds failed to form word-action associations, 18-month-olds in Experiment 2 provided reliable evidence of doing so. Additional experiments explored why 14-month-olds may not have formed such an association. Experiment 3 examined 14-month-olds' ability to discriminate a change in either the action or the label when the other element was held constant. Infants discriminated the change in label but not the change in action. When the language labels were replaced with music (Experiments 4-6), 14-month-old infants responded in terms of and discriminated between pushing and pulling. These results, in comparison with those from Experiments 1 and 3, suggest that for 14 month-olds, attempting to associate labels with actions may interfere with their discrimination of similar actions.