Dalila Ayoun provides a broad overview of parameter-setting theory in first and second language acquisition and refines the theory by revisiting and challenging the traditional assumptions that underlie it, based on cross-linguistic language data that cover a range of syntactic and phonological phenomena.

This book is perhaps the most stunning available demonstration of the explanatory power of the parametric approach to linguistic theory. It is akin, not to a deductive proof, but to the discovery of a footprint in a far-off place which leaves an archeologist elated. The book is full of intricate reasoning, but the stunning aspect is that the reasoning moves between not only complex syntax and diverse languages, but it makes predictions about what two-year-old children will assume about the jumble of linguistic input that confronts them. Those predictions, Hyams shows, are supported by a discriminating analysis of acquisition data in English and Italian. Let us examine the linguistic context for a moment before we discuss her theory. The ultimate issue in linguistic theory is the explanation of how a child can acquire any human language. To capture this fact we must posit an innate mechanism which meets two opposite constraints: it must be broad enough to account for the diversity of human language, and narrow enough so that the child does not make irrelevant hypotheses about his own language, particularly ones from which there is no recovery. That is, a child must not posit a grammar which permits all of the sentences of a language as well as other sentences which are not in the language. In a word, the child must not create a language in which one cannot make adult discriminations between grammatical and ungrammatical.

This book provides a broad overview of parameter-setting theory in first and second language acquisition and refines the theory by revisiting and challenging the traditional assumptions that underlie it, based on cross-linguistic language data that cover a range of syntactic and phonological phenomena. From an historical perspective on parameter-setting theory to an introduction to its role in computational linguistics, neurolinguistics, and language change, the reader will find a critique of the most commonly made arguments, as well as an index of all the syntactic, phonological, lexical, and morphological parameters presented in the literature to date. A closer look at the theory itself addresses the following questions: What does a parameter-setting approach to language acquisition entail? What are the underpinnings of the theory? What issues and problems remain to be solved? The empirical studies carried out to test the null subject parameter and verb movement parameter are reviewed to re-examine long-standing theoretical assumptions as well as the learnability implications for first and second language acquisition.

This book examines child second language acquisition within the Principles and Parameters theory of Universal Grammar (UG). Specifically, the book focuses on null-subjects in the developing grammars of children acquiring English as a second language. The book provides evidence from the longitudinal speech data of four child second language (L2) learners in order to test the predictions of a recent theory of null-subjects, namely, the Morphological Uniformity Principle (MUP). Lakshmanan argues that the child L2 acquisition data offer little or no evidence in support of the MUP s predictions regarding a developmental relation between verb inflections and null-subjects. The evidence from these child L2 data indicates that regardless of the status of null subjects in their first language, child L2 learners of English hypothesize correctly from the very beginning that English requires subjects of tensed clauses to be obligatorily overt. The failure on the part of these learners to obey this knowledge in certain structural contexts is the result of perceptual factors that are unrelated to parameter setting. The book demonstrates the value of child second language acquisition data in evaluating specific proposals within linguistic theory for a Universal principle.

Studies of language acqUiSItion have largely ignored processing prin ciples and mechanisms. Not surprisingly, questions concerning the analysis of an informative linguistic input - the potential evidence for grammatical parameter setting - have also been ignored. Especially in linguistic approaches to language acquisition, the role of language processing has not been prominent. With few exceptions (e. g. Goodluck and Tavakolian, 1982; Pinker, 1984) discussions of language perform ance tend to arise only when experimental debris, the artifact of some experiment, needs to be cleared away. Consequently, language pro cessing has been viewed as a collection of rather uninteresting perform ance factors obscuring the true object of interest, namely, grammar acquisition. On those occasions when parsing "strategies" have been incorporated into accounts of language development, they have often been discussed as vague preferences, not open to rigorous analysis. In principle, however, theories of language comprehension can and should be subjected to the same criteria of explicitness and explanatoriness as other theories, e. g. , theories of grammar. Thus their peripheral role in accounts of language development may reflect accidental factors, rather than any inherent fuzziness or irrelevance to the language acquisition problem. It seems probable that an explicit model of the way(s) processing routines are applied in acquisition would help solve some central problems of grammar acquisition, since these routines regulate the application of grammatical knowledge to novel inputs.

The term “crosscurrent” is defined as “a current flowing counter to another.” This volume represents crosscurrents in second language acquisition and linguistic theory in several respects. First, although the main currents running between linguistics and second language acquisition have traditionally flowed from theory to application, equally important contributions can be made in the other direction as well. Second, although there is a strong tendency in the field of linguistics to see “theorists” working within formal models of syntax, SLA research can contribute to linguistic theory more broadly defined to include various functional as well as formal models of syntax, theories of phonology, variationist theories of sociolinguists, etc. These assumptions formed the basis for a conference held at Stanford University during the Linguistic Institute there in the summer of 1987. The conference was organized to update the relation between second language acquisition and linguistic theory. This book contains a selection of (mostly revised and updated) papers of this conference and two newly written papers.

In recent linguistic theory, there has been an explosion of detailed studies of language variation. This volume applies such recent analyses to the study of child language, developing new approaches to change and variation in child grammars and revealing both early knowledge in several areas of grammar and a period of extended development in others. Topics dealt with include question formation, "subjectless" sentences, object gaps, rules for missing subject interpretation, passive sentences, rules for pronoun interpretation and argument structure. Leading developmental linguists and psycholinguists show how linguistic theory can help define and inform a theory of the dynamics of language development and its biological basis, meeting the growing need for such studies in programs in linguistics, psychology, and cognitive science.