Mechanisms of learning language from child-directed speech

描述（由申请人提供）：许多研究表明，儿童接受的言语量与他们的词汇量和语言发展有关：通常情况下，言语越多越好。除了数量外，儿童定向言语的其他特征也与语言发展呈正相关。提出的研究考察了其中的两个特征：变异集和偶然时间。变异集是一组有部分形式变异的相关句子，如“Roll the ball”。你会滚球吗？我们滚吧。”偶然言语发生在父母谈论孩子注意力集中的物体时。提出的跨学科研究的目标是发现儿童如何利用儿童导向语言的这些特征。哪些潜在的学习机制导致了变异集和偶然时间对语言习得的促进作用？这个问题的答案将有助于解释对孩子说话的数量与他们的语言发展之间的正相关关系。研究者将语言学、计算机科学和发展心理学结合起来，研究儿童定向言语中的变异集和偶然性对早期语言习得的贡献。他们的研究将结合幼儿自然但严格控制的单词学习研究和先进的计算模型来阐明名词和动词的社会嵌入学习机制。本研究的第一个目标是评估儿童定向言语的三个特性对名词和动词学习的影响：a)变异集的存在，b)变异集内话语之间的时间滞后，以及c)变异集对儿童注意力焦点的偶然性。第二个目标是对利用这三个属性的可能的学习机制进行建模。研究人员将使用Spike Timing Dependent Plasticity （STDP）模型，这是一种生物学上合理的Hebbian学习规则的变体，该规则控制着神经组件内的连通性。计算模型将接收由相同参数组成的输入，这些参数有助于行为实验中的学习。因此，模拟学习者的群体将被创造出来，他们的语言学习表现将直接与人类儿童的语言学习表现相媲美。通过STDP模型确定的机制将有助于解释照顾者的行为如何帮助儿童调整神经组装以适应语言刺激序列。综上所述，这些拟议的研究将首次将社会互动、神经组织和语言学习联系起来。通过阐明婴儿和儿童从照顾者那里学习的机制，研究结果可以为语言障碍发展的干预提供信息，并有助于设计更有效的第二语言教学方法。

DESCRIPTION (provided by applicant): Many studies have demonstrated that the amount of speech children receive is related to their vocabulary and language development: typically, the more speech, the better. In addition to quantity, other characteristics of child-directed speech are positively related to language development. The proposed research examines two of these characteristics: variation sets and contingent timing. Variation sets are clusters of related sentences with partial variation in form, such as "Roll the ball. Can you roll the ball? Let's roll it." Contingent speech occurs when parents talk about an object on which their child's attention is focused. The goal of the proposed interdisciplinary research is to discover how children make use of these characteristics of child-directed speech. What underlying learning mechanisms are responsible for the facilitative effects of variation sets and contingent timing on language acquisition? The answer to this question will help explain the positive relation between the amount of speech directed to children and their language growth. The investigators integrate linguistics, computer science, and developmental psychology to study the contributions of variation sets and contingency in child-directed speech to early language acquisition. Their research will combine naturalistic yet tightly controlled word learning studies in young children with advanced computational modeling to elucidate mechanisms of socially embedded learning of nouns and verbs. The first goal of the research is to assess the effects on noun and verb learning of three properties of child-directed speech: a) the presence of variation sets, b) the time lag between utterances within variation sets, and c) the contingency of variation sets on the child's focus of attention. The second goal is to model the possible learning mechanisms that make use of these three properties. The investigators will use a Spike Timing Dependent Plasticity (STDP) model, which is a biologically plausible variety of the Hebbian learning rule that governs connectivity within neural assemblies. The computational model will receive input structured by the same parameters that facilitate learning in the behavioral experiments. Thus, a population of simulated learners will be created whose language learning performance will be directly comparable to that of human children. Mechanisms identified by STDP modeling will help explain how caregiver behavior assists children in tuning neural assemblies to sequences of speech stimuli. Taken together, the proposed studies will, for the first time, allow connections to be made between social interaction, neural organization, and language learning. By illuminating mechanisms by which infants and children learn from caregivers, the findings could inform interventions for disordered language development and help design more effective approaches to second-language instruction. PUBLIC HEALTH RELEVANCE: By illuminating mechanisms by which infants and children learn language from specific features of caregivers' child-directed speech, the findings could inform interventions for disordered language development. The results could also be used to help parents and early child educators create social environments that foster and support language growth. Eventually, this research could be used to design more effective approaches to second-language instruction.