Constraints on Learning from Inconsistent Input

描述(申请人提供)：所有具有正常认知能力的人类学习者，在童年时期接触过语言输入，都能获得一种看起来非常像他们输入的语言。然而，目前我们几乎不知道学习者到底是如何完成这一壮举的。我们对作为语言学习基础和支持的学习机制的本质知之甚少。这是本方案研究的重点。三个一般性问题指导着这项研究。(1)语言学习机制的制约因素是什么？(2)语言习得中涉及的学习机制是特定于语言的，还是具有更普遍的性质？(3)随着学习者年龄的增长，这些机制是否会随着时间的推移而变化？如果是这样的话，它们是如何变化的？这项拟议的研究通过调查使用微型人工语言输入中的概率和不一致模式的学习来检验这些问题。这为学习机制的制约提供了一个相当独特的视角，考察了什么可以学习，什么不可以学习的限制。前人的研究表明，学习者可以获得概率模式，但他们有时会对变异施加一致性。此外，儿童比成年人更有可能改变这种模式。本研究对前人的研究结果进行了扩展，询问了学习者与输入之间交互作用的性质。系列1询问输入的性质，是什么使一些不稳定变得可学，而另一些不能。这些研究考察了对语言中不一致模式的真实学习的局限性，询问了学习者可以进行计算的特殊性、可以进行这种计算的表征以及先前特定领域知识的影响。系列2询问学习者的性质，问学习者为什么要对不一致进行规律化。特别是，这些研究考察了工作记忆限制，而不是直接源于学习机制本身的限制，是否是影响学习者获得变异或施加规律性的重要因素。这两个系列都将以成人和儿童为对象，研究学习在发展过程中的变化。尽管这些研究的输入有些不典型，但这些研究的结果将有助于我们更广泛地理解语言习得所涉及的学习机制，并最终增加我们对正常习得和无序习得的理解。

DESCRIPTION (provided by applicant): All human learners with normal cognitive capacities who are exposed to language input in childhood manage to acquire a language that looks very much like their input. However, at present we have little idea how, exactly, learners accomplish this feat. We have little understanding of the nature of the learning mechanisms that underlie and support language learning. This is the focus of the research in this proposal. Three general questions guide the research. (1) What are the constraints on language learning mechanisms? (2) Are the learning mechanisms involved in language acquisition specific to language or are they of a more general nature? (3) Do these mechanisms change over time as learners age, and if 'so, how? The proposed research examines these questions by investigating the learning of probabilistic and inconsistent patterns in the input using miniature artificial languages. This provides a rather unique view of the constraints on learning mechanisms, examining the limits of what can and cannot be learned. Previous work has shown that learners can acquire probabilistic patterns, however they sometimes impose consistency on variation. Moreover, children are more likely to change such patterns than are adults. The present research expands on the earlier results, asking about the nature of the interaction between learners and input. Series 1 asks about the nature of the input that makes some inconstancy learnable and some not. The studies examine the limits of veridical learning of inconsistent patterns in languages, asking questions about the specificity of computations learners can perform, the representations over which such computations can be performed, and the effect of prior domain-specific knowledge. Series 2 asks about the nature of the learner, asking why learners regularize over inconsistency at all. In particular, the studies examine whether working memory constraints, rather than constraints stemming directly from the learning mechanisms themselves, are an important factor influencing whether learners acquire the variation or instead impose regularity. Both series will be conducted with adults and children to examine how learning changes over development. Although the input in the proposed studies is somewhat atypical, the results from these studies will contribute to our understanding of the learning mechanisms involved in language acquisition more generally, and ultimately, this increases our understanding of both normal and disordered acquisition.