The overgeneralization of morphological forms as a function of experience

Abstract

Eighty children ranging in age from three to nine years were exposed to puppets who used a novel regular suffix (− ip) and a variety of irregular forms to express large relative size (i.e. the larger of two objects). Each child was exposed to ten regular forms and ten irregular forms. However, half of the children in each age group heard the regular suffix used in conjunction with phonetically similar base forms, while the remaining children heard the regular suffix used in conjunction with phonetically dissimilar base forms. All of the children were exposed to the same set of irregular forms. Following the exposure session, children were given a production task in which they were asked to describe large relative size “the same way that the puppet had”. The regular and irregular base forms that had been used in the exposure condition were used in the production task. The results indicated that children found it somewhat easier to learn the regular suffix when they had heard it used in conjunction with phonetically similar base forms. However, except for the three-year-olds, children were more likely to overgeneralize the regular suffix to irregular forms when they had heard it used in conjunction with phonetically dissimilar base forms. These results suggest that the generality of the linguistic rules that children learn as they acquire their first language may depend on the nature of the instances that children hear. This in turn suggests that the input to language learning children interacts with their language learning predispositions to yield children's hypotheses about the regularities of their mother tongue.