RUI: Computational Developmental Bilingualism: A Self-Organizing Model of Bilingual Lexical Acquisition

孩子们如此轻松地掌握母语词汇的能力确实是了不起的，我们对它的科学理解才刚刚开始。从这个角度来看，在双语环境中长大的孩子学习两种不同的词汇是多么容易，这就更加引人注目了。他们的语言系统是如何发展和组织的，以应对两套不同的心理词典？认知科学家通过研究双语者在其发展过程和成年过程中的语言行为，以及他们的社会和文化背景，来解决这个问题。他们甚至已经开始研究双语的神经基础，但有一种方法没有受到太多关注，那就是使用计算模型。例如，气象学家使用飓风和龙卷风等天气系统的计算模型，不仅是为了预测它们的发生，而且是为了更基本地了解它们的动态和潜在机制。同样，认知系统模型在认知科学的许多领域都有着丰富的传统，但到目前为止，双语还不是其中之一。在美国国家科学基金会的支持下，李博士正在开发一个大规模的双语词汇发展计算模型。建模工作基于自组织连接网络，该网络先前已用于语言研究的许多领域，包括单语儿童的词汇发展。这样的自组织模型非常适合于学习和发展的问题，因为这些问题是根据平衡系统组件之间的竞争和合作的相互作用而自然产生的。在双语词汇发展的情况下，这些组成部分可以解释为正在学习的语言中的单个单词。通过以这种方式建立词汇发展模型，李博士正在研究语言学习如何从根本上是一个渐进的过程，即在早期语言学习的基础上，以后学习的双语知识和技能是如何建立起来的。这一点对双语教育以及脑外伤或疾病对双语语言处理的削弱作用具有重要意义。

The ability of children to acquire their native vocabulary with such ease is truly remarkable, and one that we are only beginning to understand scientifically. In this light it is even more remarkable how easily children raised in bilingual environments can learn two different vocabularies. How are their language systems developed and organized to cope with two different sets of mental dictionaries? Cognitive scientists have addressed this question by studying the language behaviors of bilinguals through their course of development and into adulthood, and in their social and cultural contexts. They have even begun to examine the neural bases of bilingualism, but one approach that has not received much attention is the use of computational models. Meteorologists, for instance, use computational models of weather systems like hurricanes and tornadoes, not just to predict their occurrence, but to more basically understand their dynamics and underlying mechanisms. Likewise, models of cognitive systems have a rich tradition of making progress in many areas of cognitive science, yet to date, bilingualism is not one of them.With support of the National Science Foundation, Dr. Li is developing a large-scale computational model of bilingual vocabulary development. The modeling efforts are based on self-organizing connectionist networks that have been used previously in a number of areas of language research, including vocabulary development in monolingual children. Such self-organizing models are well-suited to questions of learning and development, in that these questions are naturally cast in terms of balancing competitive and cooperative interactions among system components. In the case of bilingual vocabulary development, the components can be construed as individual words from the languages being learned. By modeling vocabulary development in this way, Dr. Li is investigating how language learning is a fundamentally incremental process whereby bilingual knowledge and skills learned later in life build upon earlier language learning. This point has important implications for bilingual education, and the debilitating effects that brain trauma or disease can have on bilingual language processing.