Words, objects, and actions in early lexical acquisition.

The influences of referent type (Objects vs. Actions) and within-category referent relationships (functionally similar vs. perceptually similar) upon children's acquisition of lexical concepts were examined. Twelve children aged 12 1/2-15 1/2 months at the outset served as subjects. During 10 experimental sessions over a period of 3-4 months the children were presented with 16 contrived lexical concepts. Each concept consisted of a nonsense word and four objects or four actions which served as the referents for that word. The children acquired object words and concepts in greater numbers than action words and concepts, suggestive of differences in the underlying complexity or structure of object and action concepts. The lack of significant differences in the acquisition of perceptually based and functionally based concepts suggests that children at this point in development may base lexical concepts on perceptual or functional attributes.