The acquisition of language-particular properties under impoverished input

Date of Completion

January 2005


Language, Linguistics|Psychology, Developmental




This thesis investigates the acquisition of two language particular properties in Korean: Multiple Nominative Case marking (MNC) and scrambling. It is often assumed in language acquisition research that language input available to the child is fully representative of the adult grammar, providing samples of all the relevant properties possible in the adult grammar. That seems to be true for some well-known properties such as Wh-movement or Pro-drop. This thesis reports cases of other types which challenge such an assumption. We observe from the study of Korean data that the positive evidence for MNC and scrambling is drastically rare, raising a learnability question: how do children acquire those Korean language particular properties under the impoverished input? ^ By investigating the learnability question, we aim to answer the following related questions: (i) To what extent does input frequency play a role in language acquisition? (ii) Is the Principles and Parameters learning theory inevitable? If so, what language specific knowledge is required to ensure the acquisition of MNC and scrambling? (iii) What kind of experience triggers the learning? We examine both child speech and parental input, and also consider syntactic theories of MNC and scrambling. The hypotheses gathered from production data and learnability implications of the syntactic theories of MNC and scrambling are finally tested in experiments. ^ The study reports several important findings. For both MNC and scrambling, we observe a very close resemblance between the child speech and the input patterns, giving the appearance that the pattern of language acquisition may be explained by an input-matching theory. However, we argue that such an impression is only apparent. My experimental results show that the child must make use of language specific hidden knowledge, providing support for the Principles and Parameters approach to language acquisition. The acquisitional findings also indicate that the triggering data may not necessarily be the sentences which directly exemplify a given property, arguing against input-driven learning approach. Further, we show that the areas of remarkable success of the child in matching input frequency are aspects of performance, not ones in which the child has to determine whether a given property is grammatical or not. ^