Discusses the inadequacies of the linguistic development theory called cognitive determinism and suggests instead the linguistic input hypothesis. Concludes that it is not either cognitive development or linguistic input that determines linguistic growth, but an interaction between them. (RM)

The hypothesis explains the early lexical development of children and the predictions of this hypothesis are shown to be consistent with available data on overextension. (Author/NCR)

Examination of the speech of eight mothers and eight fathers to their one- to two-year-olds (N=8) indicated that, while paternal speech was not more diverse than maternal speech, paternal speech did show greater use of rare vocabulary and lower use of common vocabulary. (Author/CB)

Acquisition of the words "this" and "that" was tested by a comprehension and a production task with children aged 4 and 7. It was confirmed that children would learn the spatial contrast between the words and apply it from the speakers viewpoint; non-egocentrism was not deemed necessary for correct use. (CHK)