  There was significant controversy about all the elements of this paradigm shift: philosophical tangles about the notion of representation (in what sense is the grammar ‘in the head’?), technical linguistic debates about the structure and character of grammars for specific languages and about the nature of universal grammar, controversies in psychology about the relevance of Chomskyan formalisms to experimental studies of child learners and adult speakers of a language, and on and on. But the shift held. Linguistics went from a backwater to a central player (as a model and as an integrator) in the development of cognitive science as a multi-disciplinary approach to aspects of cognition and mind. Developmental psycholinguistics, a field more or less born out of these upheavals, set out to investigate experimentally whether the details about language acquisition actually supported the Chomskyan Nativist hypotheses, and in time, many developmental psychologists broke from the reigning Empiricist paradigm and began to deploy Poverty of the Stimulus arguments in other areas of cognitive development.