The competition model is a psycholinguistic theory of language acquisition and sentence processing, developed by Elizabeth Bates and Brian MacWhinney (1981). The model suggests that the meaning of language is interpreted by comparing a number of linguistic 'cues' (signaling specific functions) within a sentence, and that language is learned through the competition of basic cognitive mechanisms inside a rich linguistic environment. According to the competition model, competitive cognitive processes operate on a phylogenetic, ontogenetic, and synchronic scale, allowing language acquisition to take place across a wide variety of chronological periods.